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Chapter Two: Project Planning

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Jlungo:

Arguably, planning of water supply projects is considered to be one of the most important stages in the design. Thus, it is strongly advised and emphasized that much time should be spent to undertake proper project planning. A proper project planning will ensure effective and efficient completion of the project successfully. In this chapter, project planning is presented in seven parts that are detailed below. These include:

* Planning considerations for water supply projects
* Project Planning steps
* Consulting the Integrated Water Resources Management and Development Plan
* Consult guideline for preparation of Water Safety Plan – resilient to climate change.
* Environmental and Social Impact Assessment (ESIA) and Strategic Environmental and Social Impact Assessment (SESIA) Compliance
* Potential Impacts of Climate Change on Water Supply Projects
* Participation of CBWSOs in Project Planning Stages

=Chapter Two: Project Planning=

==2.1 Planning Considerations for Water Supply Projects ==
Before commencement of any development of a water project, it is essential to conduct project planning. Planning is a process that should entail the following:
• Undertake ESIA and SESIA studies,
• Engagement and involvement of the local community to instill the ownership, provide the local knowledge, project buy in and accommodate community needs and requirements,
• Assess safe and reliable yield or discharge and quality of water source,
• Determination of the system layout,
• Conduct design of the water supply project,
• Implement the project in terms of construction, operation and maintenance,
• Work out to obtain a sound and robust project financing.

It should be emphasized and stressed that collection of good quality, reliable, credible and enough data should be given high priority at all stages of project implementation. Population projection methods and their relevance for rural and urban settings or areas as recommended by the National Bureau of Statistics (NBS) have to be evaluated. Demographic features such as social and economic conditions have to be studied before design projections can be established. Also, water source reliability should be carried out before any further stage of project implementation.
==2.2 Project Planning Steps==
Project planning involves a series of steps that determine how project goals will be achieved. The goals may be solicited from the existing community or a strategic plan. In an event that there is not any plan, project plans can be developed through community meetings and gatherings, councils or board meetings, special focused group discussions or other planning processes.

The main steps of project planning include:
* Step 1: Initiation
* Step 2: Pre-feasibility study
* Step 3: Feasibility study
* Step 4: Preliminary and Detailed Design
* Step 5: Project phasing
* Step 6: Procurement
* Step 7: Implementation/Construction
* Step 8: Operation and Maintenance (Management)
* Step 9: Performance Monitoring

The planning of water supply projects can be represented diagrammatically by a step wise planning cycle as shown in Figure 2.1.

==2.3 Pump Protection==
The following sections provide a brief description of each of the twelve project planning steps.

===2.3.1 Initiation===
Initiation or sometimes referred to as triggering stage, is a step where initial ideas of the project are presented. Community mobilization through awareness raising is conducted at this stage. The whole idea is to inform the community on the start of the project, solicit community input and knowledge about the project area. Project common understanding is also expected to be realized at this step.

The outcome of this stage of planning is to acquire an understanding of the community conditions and identify problems that prevent the community from achieving its long-range goals. Community conditions which must be collected includes aspects of the community such as:
* Its geographic location,
* Demographics,
* Ecosystem,
* History,e.t.c

The data collection for the above information should employ community assessment methods.

[[File:Volume I Figure 2.1 Projects Planning Process.png|thumb|Figure 2.1: Projects Planning Process]]

(Source: Modified after Design Manual 3rd edition, 2009)

====2.3.1.1 Community Assessment Steps====
* Identify specific community problems that stand in the way of meeting community goals. Produce a community problem statement,
* Creates a work plan for addressing problems and attaining the goals,
* Describe measurable beneficial impacts to the community that result from the project’s implementation,
* Determine the level of resources or funding necessary to implement the project.
* Solicit community social economic assessment report from Local Government Authorities for use in choice of technology to achieve project sustainability

====2.3.1.2 Methods of conducting community assessment====
Two methods can be employed for conducting community assessment. They are comprehensive and strategic planning.

=====2.3.1.2.1 Comprehensive community assessment=====
This process should involve:
* Completing a community-wide needs assessment to engage the community in identifying and prioritizing all long-range goals and the community problems preventing the achievement of those goals,
* Next, the community is involved in the process of developing a method to accomplish long-range goals,
* Discussing initial ways to overcome the problems
* Develop measures to monitor progress towards achieving those goals.

Comprehensive plans require at least a year to complete and should cover a five- to ten-year time span.

======2.3.1.2.2 Strategic community assessment======
This is a process used when a community or an organization already has a comprehensive plan and wants to move forward to achieve its long-range goals. Strategic planning involves:
Participation of the community in identifying problems that stand between the community and its goals and to move the community towards realizing its long-range vision.

The product of strategic planning, simply called the “strategic plan,” builds on pre-established long-range goals by designing projects related to one or more of these goals. A strategic plan generally takes at least six months to complete.

===2.3.2 Pre-feasibility Study===
The pre-feasibility study stage involves initial fieldwork and studies of alternative water resource development plans. The report issued is an outline of possibilities and a list of all the fieldwork activities that need to be accomplished at a feasibility study or even a preliminary engineering design stage.

The objective of this initial study is to determine whether it is worthwhile to proceed with more detailed investigations. In other words at this stage, various projects or alternatives are screened and this should normally reduce the number of options considered feasible to no more than three or so. The report should, however, contain recommendations on the proposed project and how to proceed with the detailed investigations.

These should include indications on the following:

* Data to be collected,
* Remaining alternatives to be considered and investigated,
* Professional human resources required,
* Estimate of time that will be taken or needed,
* Budgetary financial requirements.

The above are considered taking into account:

* Long term needs,
* Deficiencies in the existing system (if any),
* Phases of project implementation.

Briefly, the pre-feasibility report should give an outline of the future development, which seems most appropriate to provide the project area with water in the long term. The other major aim may be to select a short-term project that may be implemented to overcome any immediate needs (crash programme) while the long-term project is being prepared.

===2.3.3 Feasibility Study===
The feasibility study stage develops the pre-feasibility work further and ends with a Report which normally concentrates on the project alternatives that were recommended for more detailed consideration at the pre-feasibility stage.

The study has to be carried out by a team of competent and experienced personnel from the Ministry, RUWASA and WWSA or with the help of a private sector. At this stage, the following should be achieved:

* Collection of sufficient design data,
* Appraise the alternatives,
* Alternative plans (projects) adequately studied and evaluated,
* Socio-economic analysis adequately conducted and completed
* Solicit the views and preferences with community in an open meeting
* Discuss the merits and demerits with community representatives
* Rank alternatives on the basis of appropriate costing method and perceived ability of community to afford the costs of operation and maintenance and reach agreement in principle with concerned water officials.
* Inform the community reasons for selection of the alternative(s) and seek their agreement and approval.
* Conduct Environmental Impact assessment (EIA). For larger projects a statement on Life Cycle Assessment should be included indicating the extent of quantitative and other relevant information currently available,
* Preliminary engineering design done, including a review of alternative materials,
* Preliminary cost estimates done,
* Economic internal rate of return and financial internal rate of return,
* Carry out design to a level sufficient to enable construction to proceed either using local (District) based contractors or a Force Account approach using local sub-contractors as considered feasible and appropriate,
* Most feasible project (least cost) selected,
* Feasibility report prepared and presented to the authorities for approval

The report may also include interim progress reports, appendices of data collected during the detailed study. The feasibility report should be presented as a supporting document to apply for financing from the financing agencies.
====2.3.3.1 Water Supply Projects Ranking and Technology Selection Criteria====
=====2.3.3.1.1 Ranking of Projects=====
Projects to be implemented should be ranked on the basis of the following criteria;
* Type of technology,
* Quantity of water,
* ESIA Report comments,
* Negative environment impact,
* Quality of water available,
* Cost/benefit analysis,
* Walking distance scheme complexity.

=====2.3.3.1.2 Choice of Technology=====
As far as possible ranking of project selection is concerned, technology choice should be based on progressive consideration of:
* Hand pump(s) from proven permanent deep hand dug well(s) or shallow borehole(s),
* Gravity scheme from protected spring,
* Medium or deep well with appropriate hand pump (rotary type),
* Pumped / Piped Scheme Electrical Driven,
* Pumped/Piped Scheme Solar Driven.

For point water sources or simple distribution systems, a prime location for a domestic point should be the village primary school followed by a village health facility (if any). Provision of improved sanitation and hand washing facilities at both primary school and health facility should also receive priority consideration in any village scheme. Use the relevant WASH guidelines for design of the washing facilities.

===2.3.4 Preliminary and Detailed Design===
After the feasibility report is presented and approved, the preliminary and the preferred alternative should be selected and the finances sought. The following should be considered while conducting the design:
* The Engineer should prepare the preliminary engineering design and then the detailed or final project report,
* These reports should provide the basis for implementation,
* The initial report has to provide the design basics which are then developed further in the detailed design of the project including working drawings and tender documents,
* They should however include a review of all relevant aspects of this DCOM Manual and either accept or otherwise indicate, complete with detailed reasoning, why different criteria is proposed.

In addition, the report should address the following:
* The issue of costing being adopted and requirement for extent of whole life cycle analysis and adaptation of costing,
* Consideration of the environmental impacts of the project and its envisaged elements,
* Issue of climate change and its possible effects on the project being designed.

It should be noted that the conceptual designs provided at the feasibility study or preliminary engineering stages are generally inadequate for the construction of the project. Foremost, the Engineer arranges for any outstanding detailed field investigations, surveys and data collection. Based on the detailed field data collected; detailed designs, plans and estimates are prepared.

Detailed designs should include:
* Statistical analysis of data collected for the population and demand projections; hydrological ,hydrogeological and meteorological data,
* Least cost lay-outs for different components of the project, i.e. treatment plants, hydraulic and structural works,
* Structural and stability computations of different structures,
* Calculations for pumps, motors, power generators and other machinery and equipment,
* Engineering analysis for deciding the most economic size of delivery mains.
* Hydraulic computations for the distribution system,
* Bills of quantities.
* Detailed design should include the following:

====2.3.4.1 Detailed Engineering Drawings====
These should include:

* Index plan showing overall layout of the project,
* Schematic diagram showing levels of salient components of the project (may not necessarily be to scale),
* Detailed plans and sections in scale for the headwords, treatment plants, clear water storage tank, pumping station, in a scale 1:20 to 1:100 depending on the details and size of the works,
* Detailed structural plans for structures, intake, treatment plant, clear water reservoir etc., in a scale of 1:20,
* Index plan of the distribution system normally in an appropriate scale,
* Longitudinal sections of the delivery main and details of appurtenances in scales: Horizontal scale 1:500 to 1:5000 depending on distance and details Vertical scale 1:20 to 1:100 depending on the terrain surface undulations.

====2.3.4.2 Detailed estimates of capital costs====
Project cost estimates should be based on unit costs derived from recent projects of a similar magnitude, complexity and remoteness from or proximity to ports or major urban areas.

====2.3.4.3 Detailed estimates of recurrent costs====
As far as possible this should be based on unit costs provided by the operating authority or from schemes of a similar size and nature.

====2.3.4.4 Anticipated revenue====
These should be based on the recommendations made regarding tariff structures or provided by the operating authority or regulator.

====2.3.4.5 Detailed design report====
A report should accompany the detailed designs, plans and estimates elaborating on the:
* Engineering aspects,
* Financial aspects,
* Administrative aspects,
* Tender documents
* Specifications.

====2.3.4.6 Project write-up to be submitted to potential financiers====
Each Development Partner may have a different pattern of project presentation for financial request. The project document should therefore follow more guidelines as indicated by the financiers or the local funding sources where applicable.

====2.3.5 Project Phasing====
Sometimes the implementation of a project is carried out in phases due to among other things, the following reasons:
* Financial resources available,
* Opportunity cost of money,
* Economies of scale,
* Growth rate in the area,
* Rate of development in the area,
* The design (working) life of various installations,
* Development in levels of service,
* New technology or method that needs piloting before rolling it out
Once the basic design period is decided (usually between 10 and 20 years) and water demand is computed for different years, the different elements can be phased. Exceptions do occur where financial assistance capital is being used and there is fear or a probability that further trunches will not be available just a few years later.

Generally, phasing should be undertaken as follows:
(i) Dams, river and spring intakes, should be implemented in a single phase to cover all of the ultimate design demand or the hydrologically calculated water availability. This is particularly significant for dams as flood spillways form an expensive integral part and the need to raise a spillway inlet and deal with the additional energy at its exit is usually very costly.
(ii) Boreholes to be constructed in Multiple Phases according to the growth in demand.
(iii) Treatment plants and storage tanks to be constructed stepwise or in phases, according to the projected growth in demand.
(iv) Mechanical installations to be implemented in Multiple Phases according to the design life of the equipment.
(v) Pump houses constructed in a Single Phase with space for additional mechanical plant.
(vi) Rising mains and main conduits between units to be constructed to cover the ultimate demand in a single Phase.
(vii) Long transmission mains to be constructed as two parallel lines in a single Phase where funds allow or in Two Phases where not. It can be advantageous to dedicate one of two parallel transmission mains to supplying water to the terminal reservoir whilst using the second for a mix of local distribution (daytime) and conveyance to the terminal reservoir (night time).
(viii) Distribution systems to be constructed according to the growth in development in Multiple Phases.

===2.3.6 Procurement===
====2.3.6.1 Preparation of Tender Documents====
The Procurement Management Unit (PMU) using the approved templates as guided by PPRA documentation undertakes preparation of tender documents. In preparing the tender documents undertaken by PMU, unit rate contract is normally adopted for project components such as intake, delivery mains, distribution system, storage tanks and other appurtenances. For specialized areas like the treatment plants and pumping stations it may be necessary to prepare separate tenders for the supply and installation of such facilities. The superstructure may still be included in the main contract bill of quantities. As much as possible one contract is preferred. The suppliers of such specialized equipment would then be included as sub-contractors of the main contractor. Important documents included in contract documents includes:
* Letter of Invitation to Tender
* Instruction to Tenderers
* General Conditions of Contract
* Special Conditions of Contract
* Drawings
* Specifications
* Bills of Quantities
* Tender Forms
* Security Forms
* Anti-bribery Pledge
* Schedule of Additional Information
* Information Data

====2.3.6.2 Tendering process====
This process involves use of public procurement act to select service providers as detailed in following steps;
* Issue of tender documents
* Submission and receipt of tenders
* Opening of tenders
* Evaluation of tenders
* Award of tender
* Signing of contract agreement

===2.3.7 Implementation/Construction Stage===
Construction stage includes contract management, Contract supervision and administration.
====2.3.7.1 Contract Management====
Contract management entails the following;
* Contract Management Plan (CMP),
* Contract Delivery Follow-up,
* Work progress monitoring & control,
* All projects executed must have a completion report (as constructed built reports and drawings). It is essential that Engineers or Foremen keep an up to date record of all project activities including all changes to the original design with reasons for this clearly indicated as well as the approving authority.
* Initial and Final Acceptance of the Works
* Contract Close Out
====2.3.7.2 Contract supervision and administration ====
During construction stage, it is necessary to consider the following;
* Each phase of the project implementation should be planned in detail using techniques such as the Critical Path Method (CPM) or Programme Evaluation or/and Review Technique (PERT ) to ensure time control,
* Work together with the Contractor to prepare a Quality Assurance Plan which shall narrate the scope of the works and the expected quality requirements for the project, the role of the participants in ensuring quality requirements are met
* Obtain a cash flow forecast from the contractor, and make the Client aware of his payment obligations based on the forecast
* Keep a close track of all contractors approved claims and adjust the contract price to reflect increase or decrease in the contract price
* Detailed information in procurement, contract management, contract supervision and administration is detailed well in chapter three and four of Volume III Construction Supervision for Water Supply and Sanitation Projects.

===2.3.8 Operation and Maintenance Stage===
This process takes over after the project completion, it involves;
* Preparation of O&M Plan,
* Development of Individual Unit Plans for O&M,
* Plan for capacity Building of O&M Personnel,
* Plan for Providing Spares and Tools,
* Plan for Water Audit and Leakage Control,
* Plan for Efficient Use of Power,
* Plan for sound financial management system,
* Plan for Information Education Communication for Water and Sanitation Services,
* Reports and Record Keeping,
* Develop appropriate maintenance schedule and check lists,
* Utilize Standard Operating Procedures,
* Utilize Water Safety Plans.

Detailed information on planning for operation and maintenance is found in chapter three and four of Volume IV Operation and Maintenance of Water Supply and Sanitation Projects

===2.3.9 Performance Monitoring===
The aim of the project is to provide the services uninterrupted. To ensure this, a proper monitoring mechanism of the performance of the project should be prepared. Such a mechanism could include proper procedures for procurement and distribution of spare parts, fuel, replacement, a maintenance programme for the project including personnel at the village, District and if necessary at Regional and National levels also. Likewise a water quality surveillance procedure should be instituted in the framework of the existing mechanism.

==2.4 Consulting the Integrated Water Resources Management and Development (IWRMD) Plans==
It is imperative that during planning of the water supply and sanitation project, designer should consult the Integrated Water Resources Management and Development (IWRMD) plan for a basin where the project is planned to be executed. The development of an IWRMD Plan is a key objective of the water resources component of the Water Sector Development Programme 2006-2025. It is a legal requirement provided for in the Water Resources Management Act, No. 11 of 2009. The plan provides a blueprint for sustainable development and management of the basin’s water resources.

Thus, a water supply and sanitation project designer is advised and encouraged to consult IWRMD plans as they provide:

* The status of water resource availability (both quantity and quality) in the basin,
* Water data and information necessary for the design of the projects,
* Framework for water allocations among its competing demands,
* Water demand for water related sectors,
* Stakeholders consultation plan.

===2.4.1 Status of Development and Implementation of IWRMD Plans===
By the time of development of this DCOM manual, IWRMD plans had been developed for six (6) out of the nine basins. The six basins are:
* Rufiji River Basin,
* Ruvuma and Southern Coast Basin,
* Lake Tanganyika Basin,
* Lake Nyasa Basin,
* Internal Drainage and
* Lake Rukwa Basin

It was reported that the development of IWRMD plans for Lake Victoria Basin and Wami/Ruvu basins were on-going.

IWRMD plans implementation challenges have been observed in some basins. These include:

* Inadequate funding to implement plans recommendations,
* Some plans are not implementable because of including unrealistic recommendations,
* Some plans are considered to have been more of studies rather than plans,
* Inadequate human resources capacity to implement them,
* As required by EMA, ESIAs have not been conducted, contrary to the requirement

===2.4.2 Components of IWRMD Plans===
The developed IWRMD plans are expected to have the following main components:
* Component 1: Inventory and review of water availability, use and demand,
* Component 2: Institutional, Policy and legal framework,
* Component 3: Sector/Thematic Water Plans,
* Component 4: Integrated Water Resources Management and Development Plan,
* Component 5: IWRMD Plan Implementation Strategy and Action Plan.

The production capacity of a source is very important in planning a water supply system. An estimate of the water that can be reliably produced by a water source like a well or spring gives the planner a basis to decide for or against its development. For the source(s) to be considered adequate, they must at least satisfy the maximum daily demand of the area to be served.

==2.5 Consult Guidelines for Preparation of Water Safety Plans - Resilient to Climate Change ==

Water Safety Plan (WSP) is the most effective means of consistently ensuring the safety of a drinking-water supply through the use of a comprehensive risk assessment and risk management approach that encompasses all steps in water supply from the catchment to the consumer (WHO, 2017). The approach enables the operators and managers of water utilities to know the system thoroughly, identify where and how problems could arise, put multiple barriers and management systems in place to stop the problems before they happen and making all parts of the system work properly so as to ensure the safety and acceptability of a drinking water supply intended for human consumption and other domestic uses as summarized in the WHO safe water chain frameworks.

Thus, during the planning phase, a designer should consult guidelines for the preparation of Water Safety Plans - Resilient to Climate Change, which has been prepared and published by Ministry of Water (MoW, 2015)

==2.6 Environmental and Social Impact Assessment Compliance==
Section 81 of the Environmental Management Act (Cap 191) requires all developers of projects identified in the 3rd Schedule of the Act and detailed in the 1st Schedule of the Environmental Management (Environmental Impact Assessment And Audit) (Amendment) Regulations, 2018, to undertake Environmental Impact Assessment (EIA). Section 82 of EMA (Cap 181) requires that the EIA be carried out prior to the commencement or financing of the project. Procedures for carrying out the EIA, identified under the EIA and Audit (Amendment) Regulations of 2018 identify eight steps to be followed. According to EIA and Audit (Amendment) Regulations of 2018, projects are classified into the following categories, namely:

(a) “A” category for Mandatory projects;
(b) “B1” category for Borderline Project;
(c) “B2” category for Non-Mandatory; and
(d) “Special Category

So it is imperative that a proponent and developer of any water supply and sanitation project categorizes their project prior to actual project implementation for the same.

===2.6.1 Procedures for Conducting ESIA in Tanzania===
Procedures for carrying out the ESIA, identified under the EIA and Audit (Amendment) Regulations of 2018 identify eight key steps to be followed in the EIA process in Tanzania. These are:

* Step 1: Registration,
* Step 2: Screening,
* Step 3: Scoping,
* Step 4: Environmental Assessment,
* Step 5: Review,
* Step 6: Recommendations of the Technical Advisory Committee (TAC),
* Step 7: Submission To The Minister For Environment,
* Step 8: Approval of the EIS.

It is recommended to consult NEMC guidelines and Environmental Management (Environmental Impact Assessment And Audit) (Amendment) Regulations, 2018 for more details. Also, the following Ministry of Water guidelines, accessible at have to be consulted.
a) Guidelines of Good Environmental and Social Practices (GGESP) of July 2019,
b) Environmental and Social Management Framework (ESMF) of July 2019.

===2.6.2 Strategic Environmental and Social Assessment (SESA) Compliance===

Section 105 part (2) of the Environmental Act requires that wherever there is a major water project planned for construction, the Ministry responsible for water should conduct Strategic Environmental and Social Assessment. The strategic environmental assessment shall asses the area marked for development and include:

* Baseline environmental conditions and status of natural resources,
* Identification of ecological sensitive and protected areas,
* Identification and description of communities around the area,
* Existing social-economic conditions,
* Existing economic activities and infrastructure.
The strategic environmental and social assessment shall be submitted to the Minister responsible for Environment for approval before the planning process.

==2.7 Potential Impacts of Climate Change on Water Supply Projects==
It should be emphasized that immediately the project is conceived, hydrological, rainfall and other meteorological data collection must be initiated. In addition and given the long design life of such structures, consideration must be given to the possible impacts of climate change. Detailed account of predictions and impacts of climate change on water supply projects is provided in Appendix A.

URT (2019) has recommended strategies and plans to adapt risks from climate change. The design related strategies of infrastructure, which a designer should consider while planning for water supply projects include:

* Where possible, have at least two sources of supply at different locations. Build superstructures above high flood-line level.
* Adopt energy-efficiency programmes and, where possible, select facilities which require less power consumption.
* Monitor wells near coastlines to prevent salinization. If climate change causes sea levels to rise dramatically, even aquifers that have been sustainably utilized can suffer salinization.
* Utilize renewable energy sources.

Guidelines for resiliency to climate change for urban water supply utilities have been published by the Ministry of Water.

==2.8 Participation of Community Based Water Supply Organizations (CBWSO) in Various Planning Stages==
As explained in detail in section 2.1 of this volume, the CBWSOs have to be involved in the complete life cycle of the project including ensuring their sustainability during operation and maintenance of the projects under the overall coordination of WSSAs and RUWASA.

==2.9 References==
Asadieh, B. and Krakauer, N.Y. (2016). Impacts of changes in precipitation amount and distribution on water resources studied using a model rainwater harvesting system. J. Am. Water Resour. Assoc. 52: 1450–1471.https://doi.org/10.1111/ 1752-1688.12472.

Gebrechorkos, S. H., Hülsmann, S., & Bernhofer, C. (2019). Regional climate projections for impact assessment studies in East Africa. Environmental Research Letters, 14(4), 044031. https://doi.org/10.1088/1748-9326/ab055a

Giannini, A., M. Biasutti, I. Held, and A. Sobel (2008). A global perspective on African climate. Clim. Change, 90: 359–383.

Hansingo, K., and C. Reason (2008). Modelling the atmospheric response to SST dipole patterns in the South Indian Ocean with a regional climate model. Meteorol. Atmos. Phys., 100: 37–52.

Hansingo, K., and C. Reason (2009). Modelling the atmospheric response over southern Africa to SST forcing in the southeast tropical Atlantic and southwest subtropical Indian Oceans. Int. J. Climatol., 29: 1001–1012.

Hermes, J., and C. Reason (2009). Variability in sea-surface temperature and winds in the tropical south-east Atlantic Ocean and regional rainfall relationships. Int. J. Climatol., 29: 11–21.

IPCC (2007). Summary for policymakers Climate Change 2007: Impacts, Adaptation and Vulnerability. Contribution of Working Group II to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change ed M L Parry, O F Canziani, J P Palutikof, P J van der Linden and C E Hanson (Cambridge: Cambridge University Press) pp 7-22.

IPCC (2014). Climate Change 2014: Summary for Policymakers, Synthesis Report. Contribution of Working Groups I, II and III to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change [Core Writing Team, R.K. Pachauri and L.A. Meyer (eds.)]. IPCC, Geneva, Switzerland, 151 pp.

Li, J., Chen, Y.D., Gan, T.Y., Lau, N. (2018). Elevated increases in human-perceived temperature under climate warming. Nat. Clim. Chang. 8: 43–47. https://doi.org/10.1038/s41558-017-0036-2.

Marchant, R., C. Mumbi, S. Behera, and T. Yamagata (2007). The Indian Ocean dipole—the unsung driver of climatic variability in East Africa. Afr. J. Ecol., 45: 4–16.

Moss, R. H. et al. (2010). The next generation of scenarios for climate change research and assessment. Nature, Vol 463, 11 February 2010, doi:10.1038/nature08823.

Pohl, B., N. Fauchereau, C. Reason, and M. Rouault (2010). Relationships between the Antarctic Oscillation, the Madden - Julian Oscillation, and ENSO, and Consequences for Rainfall Analysis. J. Clim., 23: 238–254.

Rouault, M., P. Florenchie, N. Fauchereau, and C. Reason (2003). South East tropical Atlantic warm events and southern African rainfall. Geophys. Res. Lett., 30, doi:10.1029/2002GL014840.

UNFCCC (2010). The Cancun Agreements. United Nations Framework Convention on Climate Change http://unfccc.int/meetings/cancunnov2010/meeting/6266.php, 2010.

URT (2019). Water sector development programme. Environmental and social management framework (ESMF). Revised version. Ministry of Water.

Vautard, R., Gobiet, A., Sobolowski, S., Kjellström, E., Stegehuis, A., Watkiss, P., Mendlik. T., Landgren, O., Nikulin, G., Teichmann, C. and Jacob, D. (2014). The European climate under a 2°C global warming. Environ. Res. Letters. Environ. Res. Lett. 9, 034006, doi:10.1088/1748-9326/9/3/034006.

Vigaud, N., Y. Richard, M. Rouault, and N. Fauchereau (2009). Moisture transport between the South Atlantic Ocean and southern Africa: Relationships with summer rainfall and associated dynamics. Clim. Dyn., 32: 113–123.

WHO (2017). Climate-resilient water safety plans: Managing health risks associated with climate variability and change. World Health Organization. ISBN: 978-92-4-151279-4. Retrieved from: https://www.who.int/water_sanitation_health/publications/climate-resilient-water-safety-plans/en/

Previous Page: [[Chapter One: Introduction|Chapter One: Introduction]] << >> Next Page: [[Chapter Three: Water Sources Analysis|Chapter Three: Water Sources Analysis]]

Chapter Two: Project Planning

2020-03-31T10:52:19Z

Jlungo:

<big>'''Chapter Two: Project Planning'''</big>
Arguably, planning of water supply projects is considered to be one of the most important stages in the design. Thus, it is strongly advised and emphasized that much time should be spent to undertake proper project planning. A proper project planning will ensure effective and efficient completion of the project successfully. In this chapter, project planning is presented in seven parts that are detailed below. These include:

* Planning considerations for water supply projects
* Project Planning steps
* Consulting the Integrated Water Resources Management and Development Plan
* Consult guideline for preparation of Water Safety Plan – resilient to climate change.
* Environmental and Social Impact Assessment (ESIA) and Strategic Environmental and Social Impact Assessment (SESIA) Compliance
* Potential Impacts of Climate Change on Water Supply Projects
* Participation of CBWSOs in Project Planning Stages

=Chapter Two: Project Planning=

==2.1 Planning Considerations for Water Supply Projects ==
Before commencement of any development of a water project, it is essential to conduct project planning. Planning is a process that should entail the following:
• Undertake ESIA and SESIA studies,
• Engagement and involvement of the local community to instill the ownership, provide the local knowledge, project buy in and accommodate community needs and requirements,
• Assess safe and reliable yield or discharge and quality of water source,
• Determination of the system layout,
• Conduct design of the water supply project,
• Implement the project in terms of construction, operation and maintenance,
• Work out to obtain a sound and robust project financing.

It should be emphasized and stressed that collection of good quality, reliable, credible and enough data should be given high priority at all stages of project implementation. Population projection methods and their relevance for rural and urban settings or areas as recommended by the National Bureau of Statistics (NBS) have to be evaluated. Demographic features such as social and economic conditions have to be studied before design projections can be established. Also, water source reliability should be carried out before any further stage of project implementation.
==2.2 Project Planning Steps==
Project planning involves a series of steps that determine how project goals will be achieved. The goals may be solicited from the existing community or a strategic plan. In an event that there is not any plan, project plans can be developed through community meetings and gatherings, councils or board meetings, special focused group discussions or other planning processes.

The main steps of project planning include:
* Step 1: Initiation
* Step 2: Pre-feasibility study
* Step 3: Feasibility study
* Step 4: Preliminary and Detailed Design
* Step 5: Project phasing
* Step 6: Procurement
* Step 7: Implementation/Construction
* Step 8: Operation and Maintenance (Management)
* Step 9: Performance Monitoring

The planning of water supply projects can be represented diagrammatically by a step wise planning cycle as shown in Figure 2.1.

==2.3 Pump Protection==
The following sections provide a brief description of each of the twelve project planning steps.

===2.3.1 Initiation===
Initiation or sometimes referred to as triggering stage, is a step where initial ideas of the project are presented. Community mobilization through awareness raising is conducted at this stage. The whole idea is to inform the community on the start of the project, solicit community input and knowledge about the project area. Project common understanding is also expected to be realized at this step.

The outcome of this stage of planning is to acquire an understanding of the community conditions and identify problems that prevent the community from achieving its long-range goals. Community conditions which must be collected includes aspects of the community such as:
* Its geographic location,
* Demographics,
* Ecosystem,
* History,e.t.c

The data collection for the above information should employ community assessment methods.

[[File:Volume I Figure 2.1 Projects Planning Process.png|thumb|Figure 2.1: Projects Planning Process]]

(Source: Modified after Design Manual 3rd edition, 2009)

====2.3.1.1 Community Assessment Steps====
* Identify specific community problems that stand in the way of meeting community goals. Produce a community problem statement,
* Creates a work plan for addressing problems and attaining the goals,
* Describe measurable beneficial impacts to the community that result from the project’s implementation,
* Determine the level of resources or funding necessary to implement the project.
* Solicit community social economic assessment report from Local Government Authorities for use in choice of technology to achieve project sustainability

====2.3.1.2 Methods of conducting community assessment====
Two methods can be employed for conducting community assessment. They are comprehensive and strategic planning.

=====2.3.1.2.1 Comprehensive community assessment=====
This process should involve:
* Completing a community-wide needs assessment to engage the community in identifying and prioritizing all long-range goals and the community problems preventing the achievement of those goals,
* Next, the community is involved in the process of developing a method to accomplish long-range goals,
* Discussing initial ways to overcome the problems
* Develop measures to monitor progress towards achieving those goals.

Comprehensive plans require at least a year to complete and should cover a five- to ten-year time span.

======2.3.1.2.2 Strategic community assessment======
This is a process used when a community or an organization already has a comprehensive plan and wants to move forward to achieve its long-range goals. Strategic planning involves:
Participation of the community in identifying problems that stand between the community and its goals and to move the community towards realizing its long-range vision.

The product of strategic planning, simply called the “strategic plan,” builds on pre-established long-range goals by designing projects related to one or more of these goals. A strategic plan generally takes at least six months to complete.

===2.3.2 Pre-feasibility Study===
The pre-feasibility study stage involves initial fieldwork and studies of alternative water resource development plans. The report issued is an outline of possibilities and a list of all the fieldwork activities that need to be accomplished at a feasibility study or even a preliminary engineering design stage.

The objective of this initial study is to determine whether it is worthwhile to proceed with more detailed investigations. In other words at this stage, various projects or alternatives are screened and this should normally reduce the number of options considered feasible to no more than three or so. The report should, however, contain recommendations on the proposed project and how to proceed with the detailed investigations.

These should include indications on the following:

* Data to be collected,
* Remaining alternatives to be considered and investigated,
* Professional human resources required,
* Estimate of time that will be taken or needed,
* Budgetary financial requirements.

The above are considered taking into account:

* Long term needs,
* Deficiencies in the existing system (if any),
* Phases of project implementation.

Briefly, the pre-feasibility report should give an outline of the future development, which seems most appropriate to provide the project area with water in the long term. The other major aim may be to select a short-term project that may be implemented to overcome any immediate needs (crash programme) while the long-term project is being prepared.

===2.3.3 Feasibility Study===
The feasibility study stage develops the pre-feasibility work further and ends with a Report which normally concentrates on the project alternatives that were recommended for more detailed consideration at the pre-feasibility stage.

The study has to be carried out by a team of competent and experienced personnel from the Ministry, RUWASA and WWSA or with the help of a private sector. At this stage, the following should be achieved:

* Collection of sufficient design data,
* Appraise the alternatives,
* Alternative plans (projects) adequately studied and evaluated,
* Socio-economic analysis adequately conducted and completed
* Solicit the views and preferences with community in an open meeting
* Discuss the merits and demerits with community representatives
* Rank alternatives on the basis of appropriate costing method and perceived ability of community to afford the costs of operation and maintenance and reach agreement in principle with concerned water officials.
* Inform the community reasons for selection of the alternative(s) and seek their agreement and approval.
* Conduct Environmental Impact assessment (EIA). For larger projects a statement on Life Cycle Assessment should be included indicating the extent of quantitative and other relevant information currently available,
* Preliminary engineering design done, including a review of alternative materials,
* Preliminary cost estimates done,
* Economic internal rate of return and financial internal rate of return,
* Carry out design to a level sufficient to enable construction to proceed either using local (District) based contractors or a Force Account approach using local sub-contractors as considered feasible and appropriate,
* Most feasible project (least cost) selected,
* Feasibility report prepared and presented to the authorities for approval

The report may also include interim progress reports, appendices of data collected during the detailed study. The feasibility report should be presented as a supporting document to apply for financing from the financing agencies.
====2.3.3.1 Water Supply Projects Ranking and Technology Selection Criteria====
=====2.3.3.1.1 Ranking of Projects=====
Projects to be implemented should be ranked on the basis of the following criteria;
* Type of technology,
* Quantity of water,
* ESIA Report comments,
* Negative environment impact,
* Quality of water available,
* Cost/benefit analysis,
* Walking distance scheme complexity.

=====2.3.3.1.2 Choice of Technology=====
As far as possible ranking of project selection is concerned, technology choice should be based on progressive consideration of:
* Hand pump(s) from proven permanent deep hand dug well(s) or shallow borehole(s),
* Gravity scheme from protected spring,
* Medium or deep well with appropriate hand pump (rotary type),
* Pumped / Piped Scheme Electrical Driven,
* Pumped/Piped Scheme Solar Driven.

For point water sources or simple distribution systems, a prime location for a domestic point should be the village primary school followed by a village health facility (if any). Provision of improved sanitation and hand washing facilities at both primary school and health facility should also receive priority consideration in any village scheme. Use the relevant WASH guidelines for design of the washing facilities.

===2.3.4 Preliminary and Detailed Design===
After the feasibility report is presented and approved, the preliminary and the preferred alternative should be selected and the finances sought. The following should be considered while conducting the design:
* The Engineer should prepare the preliminary engineering design and then the detailed or final project report,
* These reports should provide the basis for implementation,
* The initial report has to provide the design basics which are then developed further in the detailed design of the project including working drawings and tender documents,
* They should however include a review of all relevant aspects of this DCOM Manual and either accept or otherwise indicate, complete with detailed reasoning, why different criteria is proposed.

In addition, the report should address the following:
* The issue of costing being adopted and requirement for extent of whole life cycle analysis and adaptation of costing,
* Consideration of the environmental impacts of the project and its envisaged elements,
* Issue of climate change and its possible effects on the project being designed.

It should be noted that the conceptual designs provided at the feasibility study or preliminary engineering stages are generally inadequate for the construction of the project. Foremost, the Engineer arranges for any outstanding detailed field investigations, surveys and data collection. Based on the detailed field data collected; detailed designs, plans and estimates are prepared.

Detailed designs should include:
* Statistical analysis of data collected for the population and demand projections; hydrological ,hydrogeological and meteorological data,
* Least cost lay-outs for different components of the project, i.e. treatment plants, hydraulic and structural works,
* Structural and stability computations of different structures,
* Calculations for pumps, motors, power generators and other machinery and equipment,
* Engineering analysis for deciding the most economic size of delivery mains.
* Hydraulic computations for the distribution system,
* Bills of quantities.
* Detailed design should include the following:

====2.3.4.1 Detailed Engineering Drawings====
These should include:

* Index plan showing overall layout of the project,
* Schematic diagram showing levels of salient components of the project (may not necessarily be to scale),
* Detailed plans and sections in scale for the headwords, treatment plants, clear water storage tank, pumping station, in a scale 1:20 to 1:100 depending on the details and size of the works,
* Detailed structural plans for structures, intake, treatment plant, clear water reservoir etc., in a scale of 1:20,
* Index plan of the distribution system normally in an appropriate scale,
* Longitudinal sections of the delivery main and details of appurtenances in scales: Horizontal scale 1:500 to 1:5000 depending on distance and details Vertical scale 1:20 to 1:100 depending on the terrain surface undulations.

====2.3.4.2 Detailed estimates of capital costs====
Project cost estimates should be based on unit costs derived from recent projects of a similar magnitude, complexity and remoteness from or proximity to ports or major urban areas.

====2.3.4.3 Detailed estimates of recurrent costs====
As far as possible this should be based on unit costs provided by the operating authority or from schemes of a similar size and nature.

====2.3.4.4 Anticipated revenue====
These should be based on the recommendations made regarding tariff structures or provided by the operating authority or regulator.

====2.3.4.5 Detailed design report====
A report should accompany the detailed designs, plans and estimates elaborating on the:
* Engineering aspects,
* Financial aspects,
* Administrative aspects,
* Tender documents
* Specifications.

====2.3.4.6 Project write-up to be submitted to potential financiers====
Each Development Partner may have a different pattern of project presentation for financial request. The project document should therefore follow more guidelines as indicated by the financiers or the local funding sources where applicable.

====2.3.5 Project Phasing====
Sometimes the implementation of a project is carried out in phases due to among other things, the following reasons:
* Financial resources available,
* Opportunity cost of money,
* Economies of scale,
* Growth rate in the area,
* Rate of development in the area,
* The design (working) life of various installations,
* Development in levels of service,
* New technology or method that needs piloting before rolling it out
Once the basic design period is decided (usually between 10 and 20 years) and water demand is computed for different years, the different elements can be phased. Exceptions do occur where financial assistance capital is being used and there is fear or a probability that further trunches will not be available just a few years later.

Generally, phasing should be undertaken as follows:
(i) Dams, river and spring intakes, should be implemented in a single phase to cover all of the ultimate design demand or the hydrologically calculated water availability. This is particularly significant for dams as flood spillways form an expensive integral part and the need to raise a spillway inlet and deal with the additional energy at its exit is usually very costly.
(ii) Boreholes to be constructed in Multiple Phases according to the growth in demand.
(iii) Treatment plants and storage tanks to be constructed stepwise or in phases, according to the projected growth in demand.
(iv) Mechanical installations to be implemented in Multiple Phases according to the design life of the equipment.
(v) Pump houses constructed in a Single Phase with space for additional mechanical plant.
(vi) Rising mains and main conduits between units to be constructed to cover the ultimate demand in a single Phase.
(vii) Long transmission mains to be constructed as two parallel lines in a single Phase where funds allow or in Two Phases where not. It can be advantageous to dedicate one of two parallel transmission mains to supplying water to the terminal reservoir whilst using the second for a mix of local distribution (daytime) and conveyance to the terminal reservoir (night time).
(viii) Distribution systems to be constructed according to the growth in development in Multiple Phases.

===2.3.6 Procurement===
====2.3.6.1 Preparation of Tender Documents====
The Procurement Management Unit (PMU) using the approved templates as guided by PPRA documentation undertakes preparation of tender documents. In preparing the tender documents undertaken by PMU, unit rate contract is normally adopted for project components such as intake, delivery mains, distribution system, storage tanks and other appurtenances. For specialized areas like the treatment plants and pumping stations it may be necessary to prepare separate tenders for the supply and installation of such facilities. The superstructure may still be included in the main contract bill of quantities. As much as possible one contract is preferred. The suppliers of such specialized equipment would then be included as sub-contractors of the main contractor. Important documents included in contract documents includes:
* Letter of Invitation to Tender
* Instruction to Tenderers
* General Conditions of Contract
* Special Conditions of Contract
* Drawings
* Specifications
* Bills of Quantities
* Tender Forms
* Security Forms
* Anti-bribery Pledge
* Schedule of Additional Information
* Information Data

====2.3.6.2 Tendering process====
This process involves use of public procurement act to select service providers as detailed in following steps;
* Issue of tender documents
* Submission and receipt of tenders
* Opening of tenders
* Evaluation of tenders
* Award of tender
* Signing of contract agreement

===2.3.7 Implementation/Construction Stage===
Construction stage includes contract management, Contract supervision and administration.
====2.3.7.1 Contract Management====
Contract management entails the following;
* Contract Management Plan (CMP),
* Contract Delivery Follow-up,
* Work progress monitoring & control,
* All projects executed must have a completion report (as constructed built reports and drawings). It is essential that Engineers or Foremen keep an up to date record of all project activities including all changes to the original design with reasons for this clearly indicated as well as the approving authority.
* Initial and Final Acceptance of the Works
* Contract Close Out
====2.3.7.2 Contract supervision and administration ====
During construction stage, it is necessary to consider the following;
* Each phase of the project implementation should be planned in detail using techniques such as the Critical Path Method (CPM) or Programme Evaluation or/and Review Technique (PERT ) to ensure time control,
* Work together with the Contractor to prepare a Quality Assurance Plan which shall narrate the scope of the works and the expected quality requirements for the project, the role of the participants in ensuring quality requirements are met
* Obtain a cash flow forecast from the contractor, and make the Client aware of his payment obligations based on the forecast
* Keep a close track of all contractors approved claims and adjust the contract price to reflect increase or decrease in the contract price
* Detailed information in procurement, contract management, contract supervision and administration is detailed well in chapter three and four of Volume III Construction Supervision for Water Supply and Sanitation Projects.

===2.3.8 Operation and Maintenance Stage===
This process takes over after the project completion, it involves;
* Preparation of O&M Plan,
* Development of Individual Unit Plans for O&M,
* Plan for capacity Building of O&M Personnel,
* Plan for Providing Spares and Tools,
* Plan for Water Audit and Leakage Control,
* Plan for Efficient Use of Power,
* Plan for sound financial management system,
* Plan for Information Education Communication for Water and Sanitation Services,
* Reports and Record Keeping,
* Develop appropriate maintenance schedule and check lists,
* Utilize Standard Operating Procedures,
* Utilize Water Safety Plans.

Detailed information on planning for operation and maintenance is found in chapter three and four of Volume IV Operation and Maintenance of Water Supply and Sanitation Projects

===2.3.9 Performance Monitoring===
The aim of the project is to provide the services uninterrupted. To ensure this, a proper monitoring mechanism of the performance of the project should be prepared. Such a mechanism could include proper procedures for procurement and distribution of spare parts, fuel, replacement, a maintenance programme for the project including personnel at the village, District and if necessary at Regional and National levels also. Likewise a water quality surveillance procedure should be instituted in the framework of the existing mechanism.

==2.4 Consulting the Integrated Water Resources Management and Development (IWRMD) Plans==
It is imperative that during planning of the water supply and sanitation project, designer should consult the Integrated Water Resources Management and Development (IWRMD) plan for a basin where the project is planned to be executed. The development of an IWRMD Plan is a key objective of the water resources component of the Water Sector Development Programme 2006-2025. It is a legal requirement provided for in the Water Resources Management Act, No. 11 of 2009. The plan provides a blueprint for sustainable development and management of the basin’s water resources.

Thus, a water supply and sanitation project designer is advised and encouraged to consult IWRMD plans as they provide:

* The status of water resource availability (both quantity and quality) in the basin,
* Water data and information necessary for the design of the projects,
* Framework for water allocations among its competing demands,
* Water demand for water related sectors,
* Stakeholders consultation plan.

===2.4.1 Status of Development and Implementation of IWRMD Plans===
By the time of development of this DCOM manual, IWRMD plans had been developed for six (6) out of the nine basins. The six basins are:
* Rufiji River Basin,
* Ruvuma and Southern Coast Basin,
* Lake Tanganyika Basin,
* Lake Nyasa Basin,
* Internal Drainage and
* Lake Rukwa Basin

It was reported that the development of IWRMD plans for Lake Victoria Basin and Wami/Ruvu basins were on-going.

IWRMD plans implementation challenges have been observed in some basins. These include:

* Inadequate funding to implement plans recommendations,
* Some plans are not implementable because of including unrealistic recommendations,
* Some plans are considered to have been more of studies rather than plans,
* Inadequate human resources capacity to implement them,
* As required by EMA, ESIAs have not been conducted, contrary to the requirement

===2.4.2 Components of IWRMD Plans===
The developed IWRMD plans are expected to have the following main components:
* Component 1: Inventory and review of water availability, use and demand,
* Component 2: Institutional, Policy and legal framework,
* Component 3: Sector/Thematic Water Plans,
* Component 4: Integrated Water Resources Management and Development Plan,
* Component 5: IWRMD Plan Implementation Strategy and Action Plan.

The production capacity of a source is very important in planning a water supply system. An estimate of the water that can be reliably produced by a water source like a well or spring gives the planner a basis to decide for or against its development. For the source(s) to be considered adequate, they must at least satisfy the maximum daily demand of the area to be served.

==2.5 Consult Guidelines for Preparation of Water Safety Plans - Resilient to Climate Change ==

Water Safety Plan (WSP) is the most effective means of consistently ensuring the safety of a drinking-water supply through the use of a comprehensive risk assessment and risk management approach that encompasses all steps in water supply from the catchment to the consumer (WHO, 2017). The approach enables the operators and managers of water utilities to know the system thoroughly, identify where and how problems could arise, put multiple barriers and management systems in place to stop the problems before they happen and making all parts of the system work properly so as to ensure the safety and acceptability of a drinking water supply intended for human consumption and other domestic uses as summarized in the WHO safe water chain frameworks.

Thus, during the planning phase, a designer should consult guidelines for the preparation of Water Safety Plans - Resilient to Climate Change, which has been prepared and published by Ministry of Water (MoW, 2015)

==2.6 Environmental and Social Impact Assessment Compliance==
Section 81 of the Environmental Management Act (Cap 191) requires all developers of projects identified in the 3rd Schedule of the Act and detailed in the 1st Schedule of the Environmental Management (Environmental Impact Assessment And Audit) (Amendment) Regulations, 2018, to undertake Environmental Impact Assessment (EIA). Section 82 of EMA (Cap 181) requires that the EIA be carried out prior to the commencement or financing of the project. Procedures for carrying out the EIA, identified under the EIA and Audit (Amendment) Regulations of 2018 identify eight steps to be followed. According to EIA and Audit (Amendment) Regulations of 2018, projects are classified into the following categories, namely:

(a) “A” category for Mandatory projects;
(b) “B1” category for Borderline Project;
(c) “B2” category for Non-Mandatory; and
(d) “Special Category

So it is imperative that a proponent and developer of any water supply and sanitation project categorizes their project prior to actual project implementation for the same.

===2.6.1 Procedures for Conducting ESIA in Tanzania===
Procedures for carrying out the ESIA, identified under the EIA and Audit (Amendment) Regulations of 2018 identify eight key steps to be followed in the EIA process in Tanzania. These are:

* Step 1: Registration,
* Step 2: Screening,
* Step 3: Scoping,
* Step 4: Environmental Assessment,
* Step 5: Review,
* Step 6: Recommendations of the Technical Advisory Committee (TAC),
* Step 7: Submission To The Minister For Environment,
* Step 8: Approval of the EIS.

It is recommended to consult NEMC guidelines and Environmental Management (Environmental Impact Assessment And Audit) (Amendment) Regulations, 2018 for more details. Also, the following Ministry of Water guidelines, accessible at have to be consulted.
a) Guidelines of Good Environmental and Social Practices (GGESP) of July 2019,
b) Environmental and Social Management Framework (ESMF) of July 2019.

===2.6.2 Strategic Environmental and Social Assessment (SESA) Compliance===

Section 105 part (2) of the Environmental Act requires that wherever there is a major water project planned for construction, the Ministry responsible for water should conduct Strategic Environmental and Social Assessment. The strategic environmental assessment shall asses the area marked for development and include:

* Baseline environmental conditions and status of natural resources,
* Identification of ecological sensitive and protected areas,
* Identification and description of communities around the area,
* Existing social-economic conditions,
* Existing economic activities and infrastructure.
The strategic environmental and social assessment shall be submitted to the Minister responsible for Environment for approval before the planning process.

==2.7 Potential Impacts of Climate Change on Water Supply Projects==
It should be emphasized that immediately the project is conceived, hydrological, rainfall and other meteorological data collection must be initiated. In addition and given the long design life of such structures, consideration must be given to the possible impacts of climate change. Detailed account of predictions and impacts of climate change on water supply projects is provided in Appendix A.

URT (2019) has recommended strategies and plans to adapt risks from climate change. The design related strategies of infrastructure, which a designer should consider while planning for water supply projects include:

* Where possible, have at least two sources of supply at different locations. Build superstructures above high flood-line level.
* Adopt energy-efficiency programmes and, where possible, select facilities which require less power consumption.
* Monitor wells near coastlines to prevent salinization. If climate change causes sea levels to rise dramatically, even aquifers that have been sustainably utilized can suffer salinization.
* Utilize renewable energy sources.

Guidelines for resiliency to climate change for urban water supply utilities have been published by the Ministry of Water.

==2.8 Participation of Community Based Water Supply Organizations (CBWSO) in Various Planning Stages==
As explained in detail in section 2.1 of this volume, the CBWSOs have to be involved in the complete life cycle of the project including ensuring their sustainability during operation and maintenance of the projects under the overall coordination of WSSAs and RUWASA.

==2.9 References==
Asadieh, B. and Krakauer, N.Y. (2016). Impacts of changes in precipitation amount and distribution on water resources studied using a model rainwater harvesting system. J. Am. Water Resour. Assoc. 52: 1450–1471.https://doi.org/10.1111/ 1752-1688.12472.

Gebrechorkos, S. H., Hülsmann, S., & Bernhofer, C. (2019). Regional climate projections for impact assessment studies in East Africa. Environmental Research Letters, 14(4), 044031. https://doi.org/10.1088/1748-9326/ab055a

Giannini, A., M. Biasutti, I. Held, and A. Sobel (2008). A global perspective on African climate. Clim. Change, 90: 359–383.

Hansingo, K., and C. Reason (2008). Modelling the atmospheric response to SST dipole patterns in the South Indian Ocean with a regional climate model. Meteorol. Atmos. Phys., 100: 37–52.

Hansingo, K., and C. Reason (2009). Modelling the atmospheric response over southern Africa to SST forcing in the southeast tropical Atlantic and southwest subtropical Indian Oceans. Int. J. Climatol., 29: 1001–1012.

Hermes, J., and C. Reason (2009). Variability in sea-surface temperature and winds in the tropical south-east Atlantic Ocean and regional rainfall relationships. Int. J. Climatol., 29: 11–21.

IPCC (2007). Summary for policymakers Climate Change 2007: Impacts, Adaptation and Vulnerability. Contribution of Working Group II to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change ed M L Parry, O F Canziani, J P Palutikof, P J van der Linden and C E Hanson (Cambridge: Cambridge University Press) pp 7-22.

IPCC (2014). Climate Change 2014: Summary for Policymakers, Synthesis Report. Contribution of Working Groups I, II and III to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change [Core Writing Team, R.K. Pachauri and L.A. Meyer (eds.)]. IPCC, Geneva, Switzerland, 151 pp.

Li, J., Chen, Y.D., Gan, T.Y., Lau, N. (2018). Elevated increases in human-perceived temperature under climate warming. Nat. Clim. Chang. 8: 43–47. https://doi.org/10.1038/s41558-017-0036-2.

Marchant, R., C. Mumbi, S. Behera, and T. Yamagata (2007). The Indian Ocean dipole—the unsung driver of climatic variability in East Africa. Afr. J. Ecol., 45: 4–16.

Moss, R. H. et al. (2010). The next generation of scenarios for climate change research and assessment. Nature, Vol 463, 11 February 2010, doi:10.1038/nature08823.

Pohl, B., N. Fauchereau, C. Reason, and M. Rouault (2010). Relationships between the Antarctic Oscillation, the Madden - Julian Oscillation, and ENSO, and Consequences for Rainfall Analysis. J. Clim., 23: 238–254.

Rouault, M., P. Florenchie, N. Fauchereau, and C. Reason (2003). South East tropical Atlantic warm events and southern African rainfall. Geophys. Res. Lett., 30, doi:10.1029/2002GL014840.

UNFCCC (2010). The Cancun Agreements. United Nations Framework Convention on Climate Change http://unfccc.int/meetings/cancunnov2010/meeting/6266.php, 2010.

URT (2019). Water sector development programme. Environmental and social management framework (ESMF). Revised version. Ministry of Water.

Vautard, R., Gobiet, A., Sobolowski, S., Kjellström, E., Stegehuis, A., Watkiss, P., Mendlik. T., Landgren, O., Nikulin, G., Teichmann, C. and Jacob, D. (2014). The European climate under a 2°C global warming. Environ. Res. Letters. Environ. Res. Lett. 9, 034006, doi:10.1088/1748-9326/9/3/034006.

Vigaud, N., Y. Richard, M. Rouault, and N. Fauchereau (2009). Moisture transport between the South Atlantic Ocean and southern Africa: Relationships with summer rainfall and associated dynamics. Clim. Dyn., 32: 113–123.

WHO (2017). Climate-resilient water safety plans: Managing health risks associated with climate variability and change. World Health Organization. ISBN: 978-92-4-151279-4. Retrieved from: https://www.who.int/water_sanitation_health/publications/climate-resilient-water-safety-plans/en/

Previous Page: [[Chapter One: Introduction|Chapter One: Introduction]] << >> Next Page: [[Chapter Three: Water Sources Analysis|Chapter Three: Water Sources Analysis]]

Chapter Two: Project Planning

2020-03-31T10:51:00Z

Jlungo:

Arguably, planning of water supply projects is considered to be one of the most important stages in the design. Thus, it is strongly advised and emphasized that much time should be spent to undertake proper project planning. A proper project planning will ensure effective and efficient completion of the project successfully. In this chapter, project planning is presented in seven parts that are detailed below. These include:

* Planning considerations for water supply projects
* Project Planning steps
* Consulting the Integrated Water Resources Management and Development Plan
* Consult guideline for preparation of Water Safety Plan – resilient to climate change.
* Environmental and Social Impact Assessment (ESIA) and Strategic Environmental and Social Impact Assessment (SESIA) Compliance
* Potential Impacts of Climate Change on Water Supply Projects
* Participation of CBWSOs in Project Planning Stages

=Chapter Two: Project Planning=

==2.1 Planning Considerations for Water Supply Projects ==
Before commencement of any development of a water project, it is essential to conduct project planning. Planning is a process that should entail the following:
• Undertake ESIA and SESIA studies,
• Engagement and involvement of the local community to instill the ownership, provide the local knowledge, project buy in and accommodate community needs and requirements,
• Assess safe and reliable yield or discharge and quality of water source,
• Determination of the system layout,
• Conduct design of the water supply project,
• Implement the project in terms of construction, operation and maintenance,
• Work out to obtain a sound and robust project financing.

It should be emphasized and stressed that collection of good quality, reliable, credible and enough data should be given high priority at all stages of project implementation. Population projection methods and their relevance for rural and urban settings or areas as recommended by the National Bureau of Statistics (NBS) have to be evaluated. Demographic features such as social and economic conditions have to be studied before design projections can be established. Also, water source reliability should be carried out before any further stage of project implementation.
==2.2 Project Planning Steps==
Project planning involves a series of steps that determine how project goals will be achieved. The goals may be solicited from the existing community or a strategic plan. In an event that there is not any plan, project plans can be developed through community meetings and gatherings, councils or board meetings, special focused group discussions or other planning processes.

The main steps of project planning include:
* Step 1: Initiation
* Step 2: Pre-feasibility study
* Step 3: Feasibility study
* Step 4: Preliminary and Detailed Design
* Step 5: Project phasing
* Step 6: Procurement
* Step 7: Implementation/Construction
* Step 8: Operation and Maintenance (Management)
* Step 9: Performance Monitoring

The planning of water supply projects can be represented diagrammatically by a step wise planning cycle as shown in Figure 2.1.

==2.3 Pump Protection==
The following sections provide a brief description of each of the twelve project planning steps.

===2.3.1 Initiation===
Initiation or sometimes referred to as triggering stage, is a step where initial ideas of the project are presented. Community mobilization through awareness raising is conducted at this stage. The whole idea is to inform the community on the start of the project, solicit community input and knowledge about the project area. Project common understanding is also expected to be realized at this step.

The outcome of this stage of planning is to acquire an understanding of the community conditions and identify problems that prevent the community from achieving its long-range goals. Community conditions which must be collected includes aspects of the community such as:
* Its geographic location,
* Demographics,
* Ecosystem,
* History,e.t.c

The data collection for the above information should employ community assessment methods.

[[File:Volume I Figure 2.1 Projects Planning Process.png|thumb|Figure 2.1: Projects Planning Process]]

(Source: Modified after Design Manual 3rd edition, 2009)

====2.3.1.1 Community Assessment Steps====
* Identify specific community problems that stand in the way of meeting community goals. Produce a community problem statement,
* Creates a work plan for addressing problems and attaining the goals,
* Describe measurable beneficial impacts to the community that result from the project’s implementation,
* Determine the level of resources or funding necessary to implement the project.
* Solicit community social economic assessment report from Local Government Authorities for use in choice of technology to achieve project sustainability

====2.3.1.2 Methods of conducting community assessment====
Two methods can be employed for conducting community assessment. They are comprehensive and strategic planning.

=====2.3.1.2.1 Comprehensive community assessment=====
This process should involve:
* Completing a community-wide needs assessment to engage the community in identifying and prioritizing all long-range goals and the community problems preventing the achievement of those goals,
* Next, the community is involved in the process of developing a method to accomplish long-range goals,
* Discussing initial ways to overcome the problems
* Develop measures to monitor progress towards achieving those goals.

Comprehensive plans require at least a year to complete and should cover a five- to ten-year time span.

======2.3.1.2.2 Strategic community assessment======
This is a process used when a community or an organization already has a comprehensive plan and wants to move forward to achieve its long-range goals. Strategic planning involves:
Participation of the community in identifying problems that stand between the community and its goals and to move the community towards realizing its long-range vision.

The product of strategic planning, simply called the “strategic plan,” builds on pre-established long-range goals by designing projects related to one or more of these goals. A strategic plan generally takes at least six months to complete.

===2.3.2 Pre-feasibility Study===
The pre-feasibility study stage involves initial fieldwork and studies of alternative water resource development plans. The report issued is an outline of possibilities and a list of all the fieldwork activities that need to be accomplished at a feasibility study or even a preliminary engineering design stage.

The objective of this initial study is to determine whether it is worthwhile to proceed with more detailed investigations. In other words at this stage, various projects or alternatives are screened and this should normally reduce the number of options considered feasible to no more than three or so. The report should, however, contain recommendations on the proposed project and how to proceed with the detailed investigations.

These should include indications on the following:

* Data to be collected,
* Remaining alternatives to be considered and investigated,
* Professional human resources required,
* Estimate of time that will be taken or needed,
* Budgetary financial requirements.

The above are considered taking into account:

* Long term needs,
* Deficiencies in the existing system (if any),
* Phases of project implementation.

Briefly, the pre-feasibility report should give an outline of the future development, which seems most appropriate to provide the project area with water in the long term. The other major aim may be to select a short-term project that may be implemented to overcome any immediate needs (crash programme) while the long-term project is being prepared.

===2.3.3 Feasibility Study===
The feasibility study stage develops the pre-feasibility work further and ends with a Report which normally concentrates on the project alternatives that were recommended for more detailed consideration at the pre-feasibility stage.

The study has to be carried out by a team of competent and experienced personnel from the Ministry, RUWASA and WWSA or with the help of a private sector. At this stage, the following should be achieved:

* Collection of sufficient design data,
* Appraise the alternatives,
* Alternative plans (projects) adequately studied and evaluated,
* Socio-economic analysis adequately conducted and completed
* Solicit the views and preferences with community in an open meeting
* Discuss the merits and demerits with community representatives
* Rank alternatives on the basis of appropriate costing method and perceived ability of community to afford the costs of operation and maintenance and reach agreement in principle with concerned water officials.
* Inform the community reasons for selection of the alternative(s) and seek their agreement and approval.
* Conduct Environmental Impact assessment (EIA). For larger projects a statement on Life Cycle Assessment should be included indicating the extent of quantitative and other relevant information currently available,
* Preliminary engineering design done, including a review of alternative materials,
* Preliminary cost estimates done,
* Economic internal rate of return and financial internal rate of return,
* Carry out design to a level sufficient to enable construction to proceed either using local (District) based contractors or a Force Account approach using local sub-contractors as considered feasible and appropriate,
* Most feasible project (least cost) selected,
* Feasibility report prepared and presented to the authorities for approval

The report may also include interim progress reports, appendices of data collected during the detailed study. The feasibility report should be presented as a supporting document to apply for financing from the financing agencies.
====2.3.3.1 Water Supply Projects Ranking and Technology Selection Criteria====
=====2.3.3.1.1 Ranking of Projects=====
Projects to be implemented should be ranked on the basis of the following criteria;
* Type of technology,
* Quantity of water,
* ESIA Report comments,
* Negative environment impact,
* Quality of water available,
* Cost/benefit analysis,
* Walking distance scheme complexity.

=====2.3.3.1.2 Choice of Technology=====
As far as possible ranking of project selection is concerned, technology choice should be based on progressive consideration of:
* Hand pump(s) from proven permanent deep hand dug well(s) or shallow borehole(s),
* Gravity scheme from protected spring,
* Medium or deep well with appropriate hand pump (rotary type),
* Pumped / Piped Scheme Electrical Driven,
* Pumped/Piped Scheme Solar Driven.

For point water sources or simple distribution systems, a prime location for a domestic point should be the village primary school followed by a village health facility (if any). Provision of improved sanitation and hand washing facilities at both primary school and health facility should also receive priority consideration in any village scheme. Use the relevant WASH guidelines for design of the washing facilities.

===2.3.4 Preliminary and Detailed Design===
After the feasibility report is presented and approved, the preliminary and the preferred alternative should be selected and the finances sought. The following should be considered while conducting the design:
* The Engineer should prepare the preliminary engineering design and then the detailed or final project report,
* These reports should provide the basis for implementation,
* The initial report has to provide the design basics which are then developed further in the detailed design of the project including working drawings and tender documents,
* They should however include a review of all relevant aspects of this DCOM Manual and either accept or otherwise indicate, complete with detailed reasoning, why different criteria is proposed.

In addition, the report should address the following:
* The issue of costing being adopted and requirement for extent of whole life cycle analysis and adaptation of costing,
* Consideration of the environmental impacts of the project and its envisaged elements,
* Issue of climate change and its possible effects on the project being designed.

It should be noted that the conceptual designs provided at the feasibility study or preliminary engineering stages are generally inadequate for the construction of the project. Foremost, the Engineer arranges for any outstanding detailed field investigations, surveys and data collection. Based on the detailed field data collected; detailed designs, plans and estimates are prepared.

Detailed designs should include:
* Statistical analysis of data collected for the population and demand projections; hydrological ,hydrogeological and meteorological data,
* Least cost lay-outs for different components of the project, i.e. treatment plants, hydraulic and structural works,
* Structural and stability computations of different structures,
* Calculations for pumps, motors, power generators and other machinery and equipment,
* Engineering analysis for deciding the most economic size of delivery mains.
* Hydraulic computations for the distribution system,
* Bills of quantities.
* Detailed design should include the following:

====2.3.4.1 Detailed Engineering Drawings====
These should include:

* Index plan showing overall layout of the project,
* Schematic diagram showing levels of salient components of the project (may not necessarily be to scale),
* Detailed plans and sections in scale for the headwords, treatment plants, clear water storage tank, pumping station, in a scale 1:20 to 1:100 depending on the details and size of the works,
* Detailed structural plans for structures, intake, treatment plant, clear water reservoir etc., in a scale of 1:20,
* Index plan of the distribution system normally in an appropriate scale,
* Longitudinal sections of the delivery main and details of appurtenances in scales: Horizontal scale 1:500 to 1:5000 depending on distance and details Vertical scale 1:20 to 1:100 depending on the terrain surface undulations.

====2.3.4.2 Detailed estimates of capital costs====
Project cost estimates should be based on unit costs derived from recent projects of a similar magnitude, complexity and remoteness from or proximity to ports or major urban areas.

====2.3.4.3 Detailed estimates of recurrent costs====
As far as possible this should be based on unit costs provided by the operating authority or from schemes of a similar size and nature.

====2.3.4.4 Anticipated revenue====
These should be based on the recommendations made regarding tariff structures or provided by the operating authority or regulator.

====2.3.4.5 Detailed design report====
A report should accompany the detailed designs, plans and estimates elaborating on the:
* Engineering aspects,
* Financial aspects,
* Administrative aspects,
* Tender documents
* Specifications.

====2.3.4.6 Project write-up to be submitted to potential financiers====
Each Development Partner may have a different pattern of project presentation for financial request. The project document should therefore follow more guidelines as indicated by the financiers or the local funding sources where applicable.

====2.3.5 Project Phasing====
Sometimes the implementation of a project is carried out in phases due to among other things, the following reasons:
* Financial resources available,
* Opportunity cost of money,
* Economies of scale,
* Growth rate in the area,
* Rate of development in the area,
* The design (working) life of various installations,
* Development in levels of service,
* New technology or method that needs piloting before rolling it out
Once the basic design period is decided (usually between 10 and 20 years) and water demand is computed for different years, the different elements can be phased. Exceptions do occur where financial assistance capital is being used and there is fear or a probability that further trunches will not be available just a few years later.

Generally, phasing should be undertaken as follows:
(i) Dams, river and spring intakes, should be implemented in a single phase to cover all of the ultimate design demand or the hydrologically calculated water availability. This is particularly significant for dams as flood spillways form an expensive integral part and the need to raise a spillway inlet and deal with the additional energy at its exit is usually very costly.
(ii) Boreholes to be constructed in Multiple Phases according to the growth in demand.
(iii) Treatment plants and storage tanks to be constructed stepwise or in phases, according to the projected growth in demand.
(iv) Mechanical installations to be implemented in Multiple Phases according to the design life of the equipment.
(v) Pump houses constructed in a Single Phase with space for additional mechanical plant.
(vi) Rising mains and main conduits between units to be constructed to cover the ultimate demand in a single Phase.
(vii) Long transmission mains to be constructed as two parallel lines in a single Phase where funds allow or in Two Phases where not. It can be advantageous to dedicate one of two parallel transmission mains to supplying water to the terminal reservoir whilst using the second for a mix of local distribution (daytime) and conveyance to the terminal reservoir (night time).
(viii) Distribution systems to be constructed according to the growth in development in Multiple Phases.

===2.3.6 Procurement===
====2.3.6.1 Preparation of Tender Documents====
The Procurement Management Unit (PMU) using the approved templates as guided by PPRA documentation undertakes preparation of tender documents. In preparing the tender documents undertaken by PMU, unit rate contract is normally adopted for project components such as intake, delivery mains, distribution system, storage tanks and other appurtenances. For specialized areas like the treatment plants and pumping stations it may be necessary to prepare separate tenders for the supply and installation of such facilities. The superstructure may still be included in the main contract bill of quantities. As much as possible one contract is preferred. The suppliers of such specialized equipment would then be included as sub-contractors of the main contractor. Important documents included in contract documents includes:
* Letter of Invitation to Tender
* Instruction to Tenderers
* General Conditions of Contract
* Special Conditions of Contract
* Drawings
* Specifications
* Bills of Quantities
* Tender Forms
* Security Forms
* Anti-bribery Pledge
* Schedule of Additional Information
* Information Data

====2.3.6.2 Tendering process====
This process involves use of public procurement act to select service providers as detailed in following steps;
* Issue of tender documents
* Submission and receipt of tenders
* Opening of tenders
* Evaluation of tenders
* Award of tender
* Signing of contract agreement

===2.3.7 Implementation/Construction Stage===
Construction stage includes contract management, Contract supervision and administration.
====2.3.7.1 Contract Management====
Contract management entails the following;
* Contract Management Plan (CMP),
* Contract Delivery Follow-up,
* Work progress monitoring & control,
* All projects executed must have a completion report (as constructed built reports and drawings). It is essential that Engineers or Foremen keep an up to date record of all project activities including all changes to the original design with reasons for this clearly indicated as well as the approving authority.
* Initial and Final Acceptance of the Works
* Contract Close Out
====2.3.7.2 Contract supervision and administration ====
During construction stage, it is necessary to consider the following;
* Each phase of the project implementation should be planned in detail using techniques such as the Critical Path Method (CPM) or Programme Evaluation or/and Review Technique (PERT ) to ensure time control,
* Work together with the Contractor to prepare a Quality Assurance Plan which shall narrate the scope of the works and the expected quality requirements for the project, the role of the participants in ensuring quality requirements are met
* Obtain a cash flow forecast from the contractor, and make the Client aware of his payment obligations based on the forecast
* Keep a close track of all contractors approved claims and adjust the contract price to reflect increase or decrease in the contract price
* Detailed information in procurement, contract management, contract supervision and administration is detailed well in chapter three and four of Volume III Construction Supervision for Water Supply and Sanitation Projects.

===2.3.8 Operation and Maintenance Stage===
This process takes over after the project completion, it involves;
* Preparation of O&M Plan,
* Development of Individual Unit Plans for O&M,
* Plan for capacity Building of O&M Personnel,
* Plan for Providing Spares and Tools,
* Plan for Water Audit and Leakage Control,
* Plan for Efficient Use of Power,
* Plan for sound financial management system,
* Plan for Information Education Communication for Water and Sanitation Services,
* Reports and Record Keeping,
* Develop appropriate maintenance schedule and check lists,
* Utilize Standard Operating Procedures,
* Utilize Water Safety Plans.

Detailed information on planning for operation and maintenance is found in chapter three and four of Volume IV Operation and Maintenance of Water Supply and Sanitation Projects

===2.3.9 Performance Monitoring===
The aim of the project is to provide the services uninterrupted. To ensure this, a proper monitoring mechanism of the performance of the project should be prepared. Such a mechanism could include proper procedures for procurement and distribution of spare parts, fuel, replacement, a maintenance programme for the project including personnel at the village, District and if necessary at Regional and National levels also. Likewise a water quality surveillance procedure should be instituted in the framework of the existing mechanism.

==2.4 Consulting the Integrated Water Resources Management and Development (IWRMD) Plans==
It is imperative that during planning of the water supply and sanitation project, designer should consult the Integrated Water Resources Management and Development (IWRMD) plan for a basin where the project is planned to be executed. The development of an IWRMD Plan is a key objective of the water resources component of the Water Sector Development Programme 2006-2025. It is a legal requirement provided for in the Water Resources Management Act, No. 11 of 2009. The plan provides a blueprint for sustainable development and management of the basin’s water resources.

Thus, a water supply and sanitation project designer is advised and encouraged to consult IWRMD plans as they provide:

* The status of water resource availability (both quantity and quality) in the basin,
* Water data and information necessary for the design of the projects,
* Framework for water allocations among its competing demands,
* Water demand for water related sectors,
* Stakeholders consultation plan.

===2.4.1 Status of Development and Implementation of IWRMD Plans===
By the time of development of this DCOM manual, IWRMD plans had been developed for six (6) out of the nine basins. The six basins are:
* Rufiji River Basin,
* Ruvuma and Southern Coast Basin,
* Lake Tanganyika Basin,
* Lake Nyasa Basin,
* Internal Drainage and
* Lake Rukwa Basin

It was reported that the development of IWRMD plans for Lake Victoria Basin and Wami/Ruvu basins were on-going.

IWRMD plans implementation challenges have been observed in some basins. These include:

* Inadequate funding to implement plans recommendations,
* Some plans are not implementable because of including unrealistic recommendations,
* Some plans are considered to have been more of studies rather than plans,
* Inadequate human resources capacity to implement them,
* As required by EMA, ESIAs have not been conducted, contrary to the requirement

===2.4.2 Components of IWRMD Plans===
The developed IWRMD plans are expected to have the following main components:
* Component 1: Inventory and review of water availability, use and demand,
* Component 2: Institutional, Policy and legal framework,
* Component 3: Sector/Thematic Water Plans,
* Component 4: Integrated Water Resources Management and Development Plan,
* Component 5: IWRMD Plan Implementation Strategy and Action Plan.

The production capacity of a source is very important in planning a water supply system. An estimate of the water that can be reliably produced by a water source like a well or spring gives the planner a basis to decide for or against its development. For the source(s) to be considered adequate, they must at least satisfy the maximum daily demand of the area to be served.

==2.5 Consult Guidelines for Preparation of Water Safety Plans - Resilient to Climate Change ==

Water Safety Plan (WSP) is the most effective means of consistently ensuring the safety of a drinking-water supply through the use of a comprehensive risk assessment and risk management approach that encompasses all steps in water supply from the catchment to the consumer (WHO, 2017). The approach enables the operators and managers of water utilities to know the system thoroughly, identify where and how problems could arise, put multiple barriers and management systems in place to stop the problems before they happen and making all parts of the system work properly so as to ensure the safety and acceptability of a drinking water supply intended for human consumption and other domestic uses as summarized in the WHO safe water chain frameworks.

Thus, during the planning phase, a designer should consult guidelines for the preparation of Water Safety Plans - Resilient to Climate Change, which has been prepared and published by Ministry of Water (MoW, 2015)

==2.6 Environmental and Social Impact Assessment Compliance==
Section 81 of the Environmental Management Act (Cap 191) requires all developers of projects identified in the 3rd Schedule of the Act and detailed in the 1st Schedule of the Environmental Management (Environmental Impact Assessment And Audit) (Amendment) Regulations, 2018, to undertake Environmental Impact Assessment (EIA). Section 82 of EMA (Cap 181) requires that the EIA be carried out prior to the commencement or financing of the project. Procedures for carrying out the EIA, identified under the EIA and Audit (Amendment) Regulations of 2018 identify eight steps to be followed. According to EIA and Audit (Amendment) Regulations of 2018, projects are classified into the following categories, namely:

(a) “A” category for Mandatory projects;
(b) “B1” category for Borderline Project;
(c) “B2” category for Non-Mandatory; and
(d) “Special Category

So it is imperative that a proponent and developer of any water supply and sanitation project categorizes their project prior to actual project implementation for the same.

===2.6.1 Procedures for Conducting ESIA in Tanzania===
Procedures for carrying out the ESIA, identified under the EIA and Audit (Amendment) Regulations of 2018 identify eight key steps to be followed in the EIA process in Tanzania. These are:

* Step 1: Registration,
* Step 2: Screening,
* Step 3: Scoping,
* Step 4: Environmental Assessment,
* Step 5: Review,
* Step 6: Recommendations of the Technical Advisory Committee (TAC),
* Step 7: Submission To The Minister For Environment,
* Step 8: Approval of the EIS.

It is recommended to consult NEMC guidelines and Environmental Management (Environmental Impact Assessment And Audit) (Amendment) Regulations, 2018 for more details. Also, the following Ministry of Water guidelines, accessible at have to be consulted.
a) Guidelines of Good Environmental and Social Practices (GGESP) of July 2019,
b) Environmental and Social Management Framework (ESMF) of July 2019.

===2.6.2 Strategic Environmental and Social Assessment (SESA) Compliance===

Section 105 part (2) of the Environmental Act requires that wherever there is a major water project planned for construction, the Ministry responsible for water should conduct Strategic Environmental and Social Assessment. The strategic environmental assessment shall asses the area marked for development and include:

* Baseline environmental conditions and status of natural resources,
* Identification of ecological sensitive and protected areas,
* Identification and description of communities around the area,
* Existing social-economic conditions,
* Existing economic activities and infrastructure.
The strategic environmental and social assessment shall be submitted to the Minister responsible for Environment for approval before the planning process.

==2.7 Potential Impacts of Climate Change on Water Supply Projects==
It should be emphasized that immediately the project is conceived, hydrological, rainfall and other meteorological data collection must be initiated. In addition and given the long design life of such structures, consideration must be given to the possible impacts of climate change. Detailed account of predictions and impacts of climate change on water supply projects is provided in Appendix A.

URT (2019) has recommended strategies and plans to adapt risks from climate change. The design related strategies of infrastructure, which a designer should consider while planning for water supply projects include:

* Where possible, have at least two sources of supply at different locations. Build superstructures above high flood-line level.
* Adopt energy-efficiency programmes and, where possible, select facilities which require less power consumption.
* Monitor wells near coastlines to prevent salinization. If climate change causes sea levels to rise dramatically, even aquifers that have been sustainably utilized can suffer salinization.
* Utilize renewable energy sources.

Guidelines for resiliency to climate change for urban water supply utilities have been published by the Ministry of Water.

==2.8 Participation of Community Based Water Supply Organizations (CBWSO) in Various Planning Stages==
As explained in detail in section 2.1 of this volume, the CBWSOs have to be involved in the complete life cycle of the project including ensuring their sustainability during operation and maintenance of the projects under the overall coordination of WSSAs and RUWASA.

==2.9 References==
Asadieh, B. and Krakauer, N.Y. (2016). Impacts of changes in precipitation amount and distribution on water resources studied using a model rainwater harvesting system. J. Am. Water Resour. Assoc. 52: 1450–1471.https://doi.org/10.1111/ 1752-1688.12472.

Gebrechorkos, S. H., Hülsmann, S., & Bernhofer, C. (2019). Regional climate projections for impact assessment studies in East Africa. Environmental Research Letters, 14(4), 044031. https://doi.org/10.1088/1748-9326/ab055a

Giannini, A., M. Biasutti, I. Held, and A. Sobel (2008). A global perspective on African climate. Clim. Change, 90: 359–383.

Hansingo, K., and C. Reason (2008). Modelling the atmospheric response to SST dipole patterns in the South Indian Ocean with a regional climate model. Meteorol. Atmos. Phys., 100: 37–52.

Hansingo, K., and C. Reason (2009). Modelling the atmospheric response over southern Africa to SST forcing in the southeast tropical Atlantic and southwest subtropical Indian Oceans. Int. J. Climatol., 29: 1001–1012.

Hermes, J., and C. Reason (2009). Variability in sea-surface temperature and winds in the tropical south-east Atlantic Ocean and regional rainfall relationships. Int. J. Climatol., 29: 11–21.

IPCC (2007). Summary for policymakers Climate Change 2007: Impacts, Adaptation and Vulnerability. Contribution of Working Group II to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change ed M L Parry, O F Canziani, J P Palutikof, P J van der Linden and C E Hanson (Cambridge: Cambridge University Press) pp 7-22.

IPCC (2014). Climate Change 2014: Summary for Policymakers, Synthesis Report. Contribution of Working Groups I, II and III to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change [Core Writing Team, R.K. Pachauri and L.A. Meyer (eds.)]. IPCC, Geneva, Switzerland, 151 pp.

Li, J., Chen, Y.D., Gan, T.Y., Lau, N. (2018). Elevated increases in human-perceived temperature under climate warming. Nat. Clim. Chang. 8: 43–47. https://doi.org/10.1038/s41558-017-0036-2.

Marchant, R., C. Mumbi, S. Behera, and T. Yamagata (2007). The Indian Ocean dipole—the unsung driver of climatic variability in East Africa. Afr. J. Ecol., 45: 4–16.

Moss, R. H. et al. (2010). The next generation of scenarios for climate change research and assessment. Nature, Vol 463, 11 February 2010, doi:10.1038/nature08823.

Pohl, B., N. Fauchereau, C. Reason, and M. Rouault (2010). Relationships between the Antarctic Oscillation, the Madden - Julian Oscillation, and ENSO, and Consequences for Rainfall Analysis. J. Clim., 23: 238–254.

Rouault, M., P. Florenchie, N. Fauchereau, and C. Reason (2003). South East tropical Atlantic warm events and southern African rainfall. Geophys. Res. Lett., 30, doi:10.1029/2002GL014840.

UNFCCC (2010). The Cancun Agreements. United Nations Framework Convention on Climate Change http://unfccc.int/meetings/cancunnov2010/meeting/6266.php, 2010.

URT (2019). Water sector development programme. Environmental and social management framework (ESMF). Revised version. Ministry of Water.

Vautard, R., Gobiet, A., Sobolowski, S., Kjellström, E., Stegehuis, A., Watkiss, P., Mendlik. T., Landgren, O., Nikulin, G., Teichmann, C. and Jacob, D. (2014). The European climate under a 2°C global warming. Environ. Res. Letters. Environ. Res. Lett. 9, 034006, doi:10.1088/1748-9326/9/3/034006.

Vigaud, N., Y. Richard, M. Rouault, and N. Fauchereau (2009). Moisture transport between the South Atlantic Ocean and southern Africa: Relationships with summer rainfall and associated dynamics. Clim. Dyn., 32: 113–123.

WHO (2017). Climate-resilient water safety plans: Managing health risks associated with climate variability and change. World Health Organization. ISBN: 978-92-4-151279-4. Retrieved from: https://www.who.int/water_sanitation_health/publications/climate-resilient-water-safety-plans/en/

Previous Page: [[Chapter One: Introduction|Chapter One: Introduction]] << >> Next Page: [[Chapter Three: Water Sources Analysis|Chapter Three: Water Sources Analysis]]

Chapter Two: Project Planning

2020-03-31T10:33:57Z

Jlungo:

Arguably, planning of water supply projects is considered to be one of the most important stages in the design. Thus, it is strongly advised and emphasized that much time should be spent to undertake proper project planning. A proper project planning will ensure effective and efficient completion of the project successfully. In this chapter, project planning is presented in seven parts that are detailed below. These include:

* Planning considerations for water supply projects
* Project Planning steps
* Consulting the Integrated Water Resources Management and Development Plan
* Consult guideline for preparation of Water Safety Plan – resilient to climate change.
* Environmental and Social Impact Assessment (ESIA) and Strategic Environmental and Social Impact Assessment (SESIA) Compliance
* Potential Impacts of Climate Change on Water Supply Projects
* Participation of CBWSOs in Project Planning Stages

=Chapter Two: Project Planning=

2.1 Planning Considerations for Water Supply Projects
Before commencement of any development of a water project, it is essential to conduct project planning. Planning is a process that should entail the following:
• Undertake ESIA and SESIA studies,
• Engagement and involvement of the local community to instill the ownership, provide the local knowledge, project buy in and accommodate community needs and requirements,
• Assess safe and reliable yield or discharge and quality of water source,
• Determination of the system layout,
• Conduct design of the water supply project,
• Implement the project in terms of construction, operation and maintenance,
• Work out to obtain a sound and robust project financing.

It should be emphasized and stressed that collection of good quality, reliable, credible and enough data should be given high priority at all stages of project implementation. Population projection methods and their relevance for rural and urban settings or areas as recommended by the National Bureau of Statistics (NBS) have to be evaluated. Demographic features such as social and economic conditions have to be studied before design projections can be established. Also, water source reliability should be carried out before any further stage of project implementation.
2.2 Project Planning Steps
Project planning involves a series of steps that determine how project goals will be achieved. The goals may be solicited from the existing community or a strategic plan. In an event that there is not any plan, project plans can be developed through community meetings and gatherings, councils or board meetings, special focused group discussions or other planning processes.

The main steps of project planning include:
Step 1: Initiation
Step 2: Pre-feasibility study
Step 3: Feasibility study
Step 4: Preliminary and Detailed Design
Step 5: Project phasing
Step 6: Procurement
Step 7: Implementation/Construction
Step 8: Operation and Maintenance (Management)
Step 9: Performance Monitoring

The planning of water supply projects can be represented diagrammatically by a step wise planning cycle as shown in Figure 2.1.

2.3 Pump Protection
The following sections provide a brief description of each of the twelve project planning steps.

2.3.1 Initiation
Initiation or sometimes referred to as triggering stage, is a step where initial ideas of the project are presented. Community mobilization through awareness raising is conducted at this stage. The whole idea is to inform the community on the start of the project, solicit community input and knowledge about the project area. Project common understanding is also expected to be realized at this step.

The outcome of this stage of planning is to acquire an understanding of the community conditions and identify problems that prevent the community from achieving its long-range goals. Community conditions which must be collected includes aspects of the community such as:
* Its geographic location,
* Demographics,
* Ecosystem,
* History,e.t.c

The data collection for the above information should employ community assessment methods.

[[File:Volume I Figure 2.1 Projects Planning Process.png|thumb|Figure 2.1: Projects Planning Process]]

(Source: Modified after Design Manual 3rd edition, 2009)

2.3.1.1 Community Assessment Steps
• Identify specific community problems that stand in the way of meeting community goals. Produce a community problem statement,
• Creates a work plan for addressing problems and attaining the goals,
• Describe measurable beneficial impacts to the community that result from the project’s implementation,
• Determine the level of resources or funding necessary to implement the project.
• Solicit community social economic assessment report from Local Government Authorities for use in choice of technology to achieve project sustainability

2.3.1.2 Methods of conducting community assessment
Two methods can be employed for conducting community assessment. They are comprehensive and strategic planning.

2.3.1.2.1 Comprehensive community assessment
This process should involve:
• Completing a community-wide needs assessment to engage the community in identifying and prioritizing all long-range goals and the community problems preventing the achievement of those goals,
• Next, the community is involved in the process of developing a method to accomplish long-range goals,
• Discussing initial ways to overcome the problems
• Develop measures to monitor progress towards achieving those goals.

Comprehensive plans require at least a year to complete and should cover a five- to ten-year time span.

2.3.1.2.2 Strategic community assessment
This is a process used when a community or an organization already has a comprehensive plan and wants to move forward to achieve its long-range goals. Strategic planning involves:
• Participation of the community in identifying problems that stand between the community and its goals and to move the community towards realizing its long-range vision.

The product of strategic planning, simply called the “strategic plan,” builds on pre-established long-range goals by designing projects related to one or more of these goals. A strategic plan generally takes at least six months to complete.

2.3.2 Pre-feasibility Study
The pre-feasibility study stage involves initial fieldwork and studies of alternative water resource development plans. The report issued is an outline of possibilities and a list of all the fieldwork activities that need to be accomplished at feasibility study or even preliminary engineering design stage.

The objective of this initial study is to determine whether it is worthwhile to proceed with more detailed investigations. In other words at this stage, various projects or alternatives are screened and this should normally reduce the number of options considered feasible to no more than three or so. The report should however contain recommendations on the proposed project and how to proceed with the detailed investigations.

These should include indications on the following:

• Data to be collected,
• Remaining alternatives to be considered and investigated,
• Professional human resources required,
• Estimate of time that will be taken or needed,
• Budgetary financial requirements.

The above are considered taking into account:

• Long term needs,
• Deficiencies in the existing system (if any),
• Phases of project implementation.

Briefly, the pre-feasibility report should give an outline of the future development, which seems most appropriate to provide the project area with water in the long term. The other major aim may be to select a short-term project that may be implemented to overcome any immediate needs (crash programme) while the long-term project is being prepared.

2.3.3 Feasibility Study
The feasibility study stage develops the pre -feasibility work further and ends with a Report which normally concentrates on the project alternatives that were recommended for more detailed consideration at the pre-feasibility stage.

The study has to be carried out by a team of competent and experienced personnel from the Ministry, RUWASA and WWSA or with the help of a private sector. At this stage the following should be achieved:

• Collection of sufficient design data,
• Appraise the alternatives,
• Alternative plans (projects) adequately studied and evaluated,
• Socio-economic analysis adequately conducted and completed
• Solicit the views and preferences with community in an open meeting
• Discuss the merits and demerits with community representatives
• Rank alternatives on the basis of appropriate costing method and perceived ability of community to afford the costs of operation and maintenance and reach agreement in principle with concerned water officials.
• Inform the community reasons for selection of the alternative(s) and seek their agreement and approval.
• Conduct Environmental Impact assessment (EIA). For larger projects a statement on Life Cycle Assessment should be included indicating the extent of quantitative and other relevant information currently available,
• Preliminary engineering design done, including a review of alternative materials,
• Preliminary cost estimates done,
• Economic internal rate of return and financial internal rate of return,
• Carry out design to a level sufficient to enable construction to proceed either using local (District) based contractors or a Force Account approach using local sub-contractors as considered feasible and appropriate,
• Most feasible project (least cost) selected,
• Feasibility report prepared and presented to the authorities for approval

The report may also include interim progress reports, appendices of data collected during the detailed study. The feasibility report should be presented as a supporting document to apply for financing from the financing agencies.
2.3.3.1 Water Supply Projects Ranking and Technology Selection Criteria
2.3.3.1.1 Ranking of Projects
Projects to be implemented should be ranked on the basis of the following criteria;
• Type of technology,
• Quantity of water,
• ESIA Report comments,
• Negative environment impact,
• Quality of water available,
• Cost/benefit analysis,
• Walking distance scheme complexity.

2.3.3.1.2 Choice of Technology
As far as possible ranking of project selection is concerned, technology choice should be based on progressive consideration of:
− Hand pump(s) from proven permanent deep hand dug well(s) or shallow borehole(s),
− Gravity scheme from protected spring,
− Medium or deep well with appropriate hand pump (rotary type),
− Pumped / Piped Scheme Electrical Driven,
− Pumped/Piped Scheme Solar Driven.

For point water sources or simple distribution systems, a prime location for a domestic point should be the village primary school followed by a village health facility (if any). Provision of improved sanitation and hand washing facilities at both primary school and health facility should also receive priority consideration in any village scheme. Use the relevant WASH guidelines for design of the washing facilities.

2.3.4 Preliminary and Detailed Design
After the feasibility report is presented and approved, the preliminary and the preferred alternative should be selected and the finances sought. The following should be considered while conducting the design:
• The Engineer should prepare the preliminary engineering design and then the detailed or final project report,
• These reports should provide the basis for implementation,
• The initial report has to provide the design basics which are then developed further in the detailed design of the project including working drawings and tender documents,
• They should however include a review of all relevant aspects of this DCOM Manual and either accept or otherwise indicate, complete with detailed reasoning, why different criteria is proposed.

In addition the report should address the following:
• The issue of costing being adopted and requirement for extent of whole life cycle analysis and adaptation of costing,
• Consideration of the environmental impacts of the project and its envisaged elements,
• Issue of climate change and its possible effects on the project being designed.

It should be noted that the conceptual designs provided at the feasibility study or preliminary engineering stages are generally inadequate for the construction of the project. Foremost, the Engineer arranges for any outstanding detailed field investigations, surveys and data collection. Based on the detailed field data collected; detailed designs, plans and estimates are prepared.

Detailed designs should include:
• Statistical analysis of data collected for the population and demand projections; hydrological ,hydrogeological and meteorological data,
• Least cost lay-outs for different components of the project, i.e. treatment plants, hydraulic and structural works,
• Structural and stability computations of different structures,
• Calculations for pumps, motors, power generators and other machinery and equipment,
• Engineering analysis for deciding the most economic size of delivery mains.
• Hydraulic computations for the distribution system,
• Bills of quantities.
Detailed design should include the following:

2.3.4.1 Detailed Engineering Drawings
These should include:

• Index plan showing overall layout of the project,
• Schematic diagram showing levels of salient components of the project (may not necessarily be to scale),
• Detailed plans and sections in scale for the headwords, treatment plants, clear water storage tank, pumping station, in a scale 1:20 to 1:100 depending on the details and size of the works,
• Detailed structural plans for structures, intake, treatment plant, clear water reservoir etc., in a scale of 1:20,
• Index plan of the distribution system normally in an appropriate scale,
• Longitudinal sections of the delivery main and details of appurtenances in scales: Horizontal scale 1:500 to 1:5000 depending on distance and details Vertical scale 1:20 to 1:100 depending on the terrain surface undulations.

2.3.4.2 Detailed estimates of capital costs
Project cost estimates should be based on unit costs derived from recent projects of a similar magnitude, complexity and remoteness from or proximity to ports or major urban areas.

2.3.4.3 Detailed estimates of recurrent costs
As far as possible this should be based on unit costs provided by the operating authority or from schemes of a similar size and nature.

2.3.4.4 Anticipated revenue
These should be based on the recommendations made regarding tariff structures or provided by the operating authority or regulator.

2.3.4.5 Detailed design report
A report should accompany the detailed designs, plans and estimates elaborating on the:
• Engineering aspects,
• Financial aspects,
• Administrative aspects,
• Tender documents
• Specifications.

2.3.4.6 Project write-up to be submitted to potential financiers
Each Development Partner may have a different pattern of project presentation for financial request. The project document should therefore follow more guidelines as indicated by the financiers or the local funding sources where applicable.

2.3.5 Project Phasing
Sometimes the implementation of a project is carried out in phases due to among other things, the following reasons:
• Financial resources available,
• Opportunity cost of money,
• Economies of scale,
• Growth rate in the area,
• Rate of development in the area,
• The design (working) life of various installations,
• Development in levels of service,
• New technology or method that needs piloting before rolling it out
Once the basic design period is decided (usually between 10 and 20 years) and water demand is computed for different years, the different elements can be phased. Exceptions do occur where financial assistance capital is being used and there is fear or a probability that further trunches will not be available just a few years later.

Generally, phasing should be undertaken as follows:
(i) Dams, river and spring intakes, should be implemented in a single phase to cover all of the ultimate design demand or the hydrologically calculated water availability. This is particularly significant for dams as flood spillways form an expensive integral part and the need to raise a spillway inlet and deal with the additional energy at its exit is usually very costly.
(ii) Boreholes to be constructed in Multiple Phases according to the growth in demand.
(iii) Treatment plants and storage tanks to be constructed stepwise or in phases, according to the projected growth in demand.
(iv) Mechanical installations to be implemented in Multiple Phases according to the design life of the equipment.
(v) Pump houses constructed in a Single Phase with space for additional mechanical plant.
(vi) Rising mains and main conduits between units to be constructed to cover the ultimate demand in a single Phase.
(vii) Long transmission mains to be constructed as two parallel lines in a single Phase where funds allow or in Two Phases where not. It can be advantageous to dedicate one of two parallel transmission mains to supplying water to the terminal reservoir whilst using the second for a mix of local distribution (daytime) and conveyance to the terminal reservoir (night time).
(viii) Distribution systems to be constructed according to the growth in development in Multiple Phases.

2.3.6 Procurement
2.3.6.1 2.2.6.1 Preparation of Tender Documents
The Procurement Management Unit (PMU) using the approved templates as guided by PPRA documentation undertakes preparation of tender documents. In preparing the tender documents undertaken by PMU, unit rate contract is normally adopted for project components such as intake, delivery mains, distribution system, storage tanks and other appurtenances. For specialized areas like the treatment plants and pumping stations it may be necessary to prepare separate tenders for the supply and installation of such facilities. The superstructure may still be included in the main contract bill of quantities. As much as possible one contract is preferred. The suppliers of such specialized equipment would then be included as sub-contractors of the main contractor. Important documents included in contract documents includes:
• Letter of Invitation to Tender
• Instruction to Tenderers
• General Conditions of Contract
• Special Conditions of Contract
• Drawings
• Specifications
• Bills of Quantities
• Tender Forms
• Security Forms
• Anti-bribery Pledge
• Schedule of Additional Information
• Information Data

2.3.6.2 Tendering process
This process involves use of public procurement act to select service providers as detailed in following steps;
• Issue of tender documents
• Submission and receipt of tenders
• Opening of tenders
• Evaluation of tenders
• Award of tender
• Signing of contract agreement

2.3.7 Implementation/Construction Stage
Construction stage includes contract management, Contract supervision and administration.
2.3.7.1 Contract Management
Contract management entails the following;
• Contract Management Plan (CMP),
• Contract Delivery Follow-up,
• Work progress monitoring & control,
• All projects executed must have a completion report (as constructed built reports and drawings). It is essential that Engineers or Foremen keep an up to date record of all project activities including all changes to the original design with reasons for this clearly indicated as well as the approving authority.
• Initial and Final Acceptance of the Works
• Contract Close Out
2.3.7.2 Contract supervision and administration
During construction stage, it is necessary to consider the following;
• Each phase of the project implementation should be planned in detail using techniques such as the Critical Path Method (CPM) or Programme Evaluation or/and Review Technique (PERT ) to ensure time control,
• Work together with the Contractor to prepare a Quality Assurance Plan which shall narrate the scope of the works and the expected quality requirements for the project, the role of the participants in ensuring quality requirements are met
• Obtain a cash flow forecast from the contractor, and make the Client aware of his payment obligations based on the forecast
• Keep a close track of all contractors approved claims and adjust the contract price to reflect increase or decrease in the contract price
Detailed information in procurement, contract management, contract supervision and administration is detailed well in chapter three and four of Volume III Construction Supervision for Water Supply and Sanitation Projects.

2.3.8 Operation and Maintenance Stage
This process takes over after the project completion, it involves;
• Preparation of O&M Plan,
• Development of Individual Unit Plans for O&M,
• Plan for capacity Building of O&M Personnel,
• Plan for Providing Spares and Tools,
• Plan for Water Audit and Leakage Control,
• Plan for Efficient Use of Power,
• Plan for sound financial management system,
• Plan for Information Education Communication for Water and Sanitation Services,
• Reports and Record Keeping,
• Develop appropriate maintenance schedule and check lists,
• Utilize Standard Operating Procedures,
• Utilize Water Safety Plans.

Detailed information on planning for operation and maintenance is found in chapter three and four of Volume IV Operation and Maintenance of Water Supply and Sanitation Projects

2.3.9 Performance Monitoring
The aim of the project is to provide the services uninterrupted. To ensure this, a proper monitoring mechanism of the performance of the project should be prepared. Such a mechanism could include proper procedures for procurement and distribution of spare parts, fuel, replacement, a maintenance programme for the project including personnel at the village, District and if necessary at Regional and National levels also. Likewise a water quality surveillance procedure should be instituted in the framework of the existing mechanism.

2.4 Consulting the Integrated Water Resources Management and Development (IWRMD) Plans
It is imperative that during planning of the water supply and sanitation project, designer should consult the Integrated Water Resources Management and Development (IWRMD) plan for a basin where the project is planned to be executed. The development of an IWRMD Plan is a key objective of the water resources component of the Water Sector Development Programme 2006-2025. It is a legal requirement provided for in the Water Resources Management Act, No. 11 of 2009. The plan provides a blueprint for sustainable development and management of the basin’s water resources.

Thus, a water supply and sanitation project designer is advised and encouraged to consult IWRMD plans as they provide:

• The status of water resource availability (both quantity and quality) in the basin,
• Water data and information necessary for the design of the projects,
• Framework for water allocations among its competing demands,
• Water demand for water related sectors,
• Stakeholders consultation plan.

2.4.1 Status of Development and Implementation of IWRMD Plans
By the time of development of this DCOM manual, IWRMD plans had been developed for six (6) out of the nine basins. The six basins are:
• Rufiji River Basin,
• Ruvuma and Southern Coast Basin,
• Lake Tanganyika Basin,
• Lake Nyasa Basin,
• Internal Drainage and
• Lake Rukwa Basin

It was reported that the development of IWRMD plans for Lake Victoria Basin and Wami/Ruvu basins were on-going.

IWRMD plans implementation challenges have been observed in some basins. These include:

• Inadequate funding to implement plans recommendations,
• Some plans are not implementable because of including unrealistic recommendations,
• Some plans are considered to have been more of studies rather than plans,
• Inadequate human resources capacity to implement them,
• As required by EMA, ESIAs have not been conducted, contrary to the requirement

2.4.2 Components of IWRMD Plans
The developed IWRMD plans are expected to have the following main components:

• Component 1: Inventory and review of water availability, use and demand,
• Component 2: Institutional, Policy and legal framework,
• Component 3: Sector/Thematic Water Plans,
• Component 4: Integrated Water Resources Management and Development Plan,
• Component 5: IWRMD Plan Implementation Strategy and Action Plan.

The production capacity of a source is very important in planning a water supply system. An estimate of the water that can be reliably produced by a water source like a well or spring gives the planner a basis to decide for or against its development. For the source(s) to be considered adequate, they must at least satisfy the maximum daily demand of the area to be served.

2.5 Consult Guidelines for Preparation of Water Safety Plans - Resilient to Climate Change

Water Safety Plan (WSP) is the most effective means of consistently ensuring the safety of a drinking-water supply through the use of a comprehensive risk assessment and risk management approach that encompasses all steps in water supply from the catchment to the consumer (WHO, 2017). The approach enables the operators and managers of water utilities to know the system thoroughly, identify where and how problems could arise, put multiple barriers and management systems in place to stop the problems before they happen and making all parts of the system work properly so as to ensure the safety and acceptability of a drinking water supply intended for human consumption and other domestic uses as summarized in the WHO safe water chain frameworks.

Thus, during the planning phase, a designer should consult guidelines for the preparation of Water Safety Plans - Resilient to Climate Change, which has been prepared and published by Ministry of Water (MoW, 2015)

2.6 Environmental and Social Impact Assessment Compliance
Section 81 of the Environmental Management Act (Cap 191) requires all developers of projects identified in the 3rd Schedule of the Act and detailed in the 1st Schedule of the Environmental Management (Environmental Impact Assessment And Audit) (Amendment) Regulations, 2018, to undertake Environmental Impact Assessment (EIA). Section 82 of EMA (Cap 181) requires that the EIA be carried out prior to the commencement or financing of the project. Procedures for carrying out the EIA, identified under the EIA and Audit (Amendment) Regulations of 2018 identify eight steps to be followed. According to EIA and Audit (Amendment) Regulations of 2018, projects are classified into the following categories, namely:

(a) “A” category for Mandatory projects;
(b) “B1” category for Borderline Project;
(c) “B2” category for Non-Mandatory; and
(d) “Special Category

So it is imperative that a proponent and developer of any water supply and sanitation project categorizes their project prior to actual project implementation for the same.

2.6.1 Procedures for Conducting ESIA in Tanzania
Procedures for carrying out the ESIA, identified under the EIA and Audit (Amendment) Regulations of 2018 identify eight key steps to be followed in the EIA process in Tanzania. These are:

• Step 1: Registration,
• Step 2: Screening,
• Step 3: Scoping,
• Step 4: Environmental Assessment,
• Step 5: Review,
• Step 6: Recommendations of the Technical Advisory Committee (TAC),
• Step 7: Submission To The Minister For Environment,
• Step 8: Approval of the EIS.

It is recommended to consult NEMC guidelines and Environmental Management (Environmental Impact Assessment And Audit) (Amendment) Regulations, 2018 for more details. Also, the following Ministry of Water guidelines, accessible at have to be consulted.
a) Guidelines of Good Environmental and Social Practices (GGESP) of July 2019,
b) Environmental and Social Management Framework (ESMF) of July 2019.

2.6.2 Strategic Environmental and Social Assessment (SESA) Compliance

Section 105 part (2) of the Environmental Act requires that wherever there is a major water project planned for construction, the Ministry responsible for water should conduct Strategic Environmental and Social Assessment. The strategic environmental assessment shall asses the area marked for development and include:

• Baseline environmental conditions and status of natural resources,
• Identification of ecological sensitive and protected areas,
• Identification and description of communities around the area,
• Existing social-economic conditions,
• Existing economic activities and infrastructure.
The strategic environmental and social assessment shall be submitted to the Minister responsible for Environment for approval before the planning process.

2.7 Potential Impacts of Climate Change on Water Supply Projects
It should be emphasized that immediately the project is conceived, hydrological, rainfall and other meteorological data collection must be initiated. In addition and given the long design life of such structures, consideration must be given to the possible impacts of climate change. Detailed account of predictions and impacts of climate change on water supply projects is provided in Appendix A.

URT (2019) has recommended strategies and plans to adapt risks from climate change. The design related strategies of infrastructure, which a designer should consider while planning for water supply projects include:

• Where possible, have at least two sources of supply at different locations. Build superstructures above high flood-line level.
• Adopt energy-efficiency programmes and, where possible, select facilities which require less power consumption.
• Monitor wells near coastlines to prevent salinization. If climate change causes sea levels to rise dramatically, even aquifers that have been sustainably utilized can suffer salinization.
• Utilize renewable energy sources.

Guidelines for resiliency to climate change for urban water supply utilities have been published by the Ministry of Water.

2.8 Participation of Community Based Water Supply Organizations (CBWSO) in Various Planning Stages
As explained in detail in section 2.1 of this volume, the CBWSOs have to be involved in the complete life cycle of the project including ensuring their sustainability during operation and maintenance of the projects under the overall coordination of WSSAs and RUWASA.

2.9 References
Asadieh, B. and Krakauer, N.Y. (2016). Impacts of changes in precipitation amount and distribution on water resources studied using a model rainwater harvesting system. J. Am. Water Resour. Assoc. 52: 1450–1471.https://doi.org/10.1111/ 1752-1688.12472.

Gebrechorkos, S. H., Hülsmann, S., & Bernhofer, C. (2019). Regional climate projections for impact assessment studies in East Africa. Environmental Research Letters, 14(4), 044031. https://doi.org/10.1088/1748-9326/ab055a

Giannini, A., M. Biasutti, I. Held, and A. Sobel (2008). A global perspective on African climate. Clim. Change, 90: 359–383.

Hansingo, K., and C. Reason (2008). Modelling the atmospheric response to SST dipole patterns in the South Indian Ocean with a regional climate model. Meteorol. Atmos. Phys., 100: 37–52.

Hansingo, K., and C. Reason (2009). Modelling the atmospheric response over southern Africa to SST forcing in the southeast tropical Atlantic and southwest subtropical Indian Oceans. Int. J. Climatol., 29: 1001–1012.

Hermes, J., and C. Reason (2009). Variability in sea-surface temperature and winds in the tropical south-east Atlantic Ocean and regional rainfall relationships. Int. J. Climatol., 29: 11–21.

IPCC (2007). Summary for policymakers Climate Change 2007: Impacts, Adaptation and Vulnerability. Contribution of Working Group II to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change ed M L Parry, O F Canziani, J P Palutikof, P J van der Linden and C E Hanson (Cambridge: Cambridge University Press) pp 7-22.

IPCC (2014). Climate Change 2014: Summary for Policymakers, Synthesis Report. Contribution of Working Groups I, II and III to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change [Core Writing Team, R.K. Pachauri and L.A. Meyer (eds.)]. IPCC, Geneva, Switzerland, 151 pp.

Li, J., Chen, Y.D., Gan, T.Y., Lau, N. (2018). Elevated increases in human-perceived temperature under climate warming. Nat. Clim. Chang. 8: 43–47. https://doi.org/10.1038/s41558-017-0036-2.

Marchant, R., C. Mumbi, S. Behera, and T. Yamagata (2007). The Indian Ocean dipole—the unsung driver of climatic variability in East Africa. Afr. J. Ecol., 45: 4–16.

Moss, R. H. et al. (2010). The next generation of scenarios for climate change research and assessment. Nature, Vol 463, 11 February 2010, doi:10.1038/nature08823.

Pohl, B., N. Fauchereau, C. Reason, and M. Rouault (2010). Relationships between the Antarctic Oscillation, the Madden - Julian Oscillation, and ENSO, and Consequences for Rainfall Analysis. J. Clim., 23: 238–254.

Rouault, M., P. Florenchie, N. Fauchereau, and C. Reason (2003). South East tropical Atlantic warm events and southern African rainfall. Geophys. Res. Lett., 30, doi:10.1029/2002GL014840.

UNFCCC (2010). The Cancun Agreements. United Nations Framework Convention on Climate Change http://unfccc.int/meetings/cancunnov2010/meeting/6266.php, 2010.

URT (2019). Water sector development programme. Environmental and social management framework (ESMF). Revised version. Ministry of Water.

Vautard, R., Gobiet, A., Sobolowski, S., Kjellström, E., Stegehuis, A., Watkiss, P., Mendlik. T., Landgren, O., Nikulin, G., Teichmann, C. and Jacob, D. (2014). The European climate under a 2°C global warming. Environ. Res. Letters. Environ. Res. Lett. 9, 034006, doi:10.1088/1748-9326/9/3/034006.

Vigaud, N., Y. Richard, M. Rouault, and N. Fauchereau (2009). Moisture transport between the South Atlantic Ocean and southern Africa: Relationships with summer rainfall and associated dynamics. Clim. Dyn., 32: 113–123.

WHO (2017). Climate-resilient water safety plans: Managing health risks associated with climate variability and change. World Health Organization. ISBN: 978-92-4-151279-4. Retrieved from: https://www.who.int/water_sanitation_health/publications/climate-resilient-water-safety-plans/en/

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Chapter Two: Project Planning

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2020-03-30T18:41:04Z

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[[Image:DCOM_Volume_I_2020-03-11.png|540px|link=Preface]]
<h4>Volume I: Design of Water Supply Projects </h4> [[Preface|Readmore...]]or Download [[:File:DCOM_Volume_I_2020-03-10.pdf| Volume I PDF]]

TABLE OF CONTENTS

[CHAPTER ONE: INTRODUCTION|CHAPTER ONE: INTRODUCTION]
{| class="wikitable"
|-
! Chapter #!! Chapter Title!! Page
|-
| i || LIST OF SPECIAL COMMITTEE MEMBERS || V
|-
| 1|| CHAPTER ONE: INTRODUCTION || 1
|-
| 1.1|| Global Considerations on Water Supply and Sanitation || 1
|-
| 1.1.1 || Global Considerations on Water Supply and Sanitation || 1
|-
| 1.1.2 || Climate Change and Resilience to Climate Change || 2
|-
| 1.1.3 || Public-Private Partnership in Water Supply and Sanitation Projects in Developing Countries || 3
|-
| 1.1.4 || International Water Law || 4
|-
| 1.2 || Development Agenda and Water and Sanitation Sector in Tanzania || 5
|-
| 1.2.1 || National Water Policy || 7
|-
| 1.2.2|| Legal and Institutional Framework for Water Supply and Sanitation Services || 8
|-
| 1.2.3 || Coverage and Access to Water Supply Services || 9
|-
| 1.2.4|| Policy Environment for Water and Sanitation Services in Tanzania || 9
|-
| 1.2.5 || Major Stakeholders in Water Supply and Sanitation Projects || 10
|-
| 1.2.6 || Water Supply and Sanitation Public Private Partnership in Tanzania || 11
|-
| 1.3 || Rationale for Preparation of the Fourth Edition DCOM Manual || 13
|-
| 1.4 || About the Fourth Edition of the DCOM Manual || 13
|-
| 1.5 || Organisation of the 4th edition of the DCOM Manual || 14
|-
| 1.6 || Purpose of this Volume || 14
|-
| 1.7 || References || 15
|-
| Example || Example || Example
|-
| Example || Example || Example
|-
| Example || Example || Example
|-
| Example || Example || Example
|}

* CHAPTER TWO 17
* PROJECT PLANNING 17
* 2.1 Planning Considerations for Water Supply Projects 17
* 2.2 Project Planning Steps 18
* 2.3 Pump Protection 18
* 2.3.1 Initiation 18
* 2.3.1.1 Community Assessment Steps 20
* 2.3.1.2 Methods of conducting community assessment 20
* 2.3.1.2.1 Comprehensive community assessment 20
* 2.3.1.2.2 Strategic community assessment 20
* 2.3.2 Pre-feasibility Study 21
* 2.3.3 Feasibility Study 21
* 2.3.3.1 Water Supply Projects Ranking and Technology Selection Criteria 22
* 2.3.3.1.1 Ranking of Projects 22
* 2.3.3.1.2 Choice of Technology 23
* 2.3.4 Preliminary and Detailed Design 23
* 2.3.4.1 Detailed Engineering Drawings 24
* 2.3.4.2 Detailed estimates of capital costs 24
* 2.3.4.3 Detailed estimates of recurrent costs 24
* 2.3.4.4 Anticipated revenue 25
* 2.3.4.5 Detailed design report 25
* 2.3.4.6 Project write-up to be submitted to potential financiers 25
* 2.3.5 Project Phasing 25
* 2.3.6 Procurement 26
* 2.3.6.1 2.2.6.1 Preparation of Tender Documents 26
* 2.3.6.2 Tendering process 27
* 2.3.7 Implementation/Construction Stage 27
* 2.3.7.1 Contract Management 27
* 2.3.7.2 Contract supervision and administration 27
* 2.3.8 Operation and Maintenance Stage 28
* 2.3.9 Performance Monitoring 28
* 2.4 Consulting the Integrated Water Resources Management and Development (IWRMD) Plans 28
* 2.4.1 Status of Development and Implementation of IWRMD Plans 29
* 2.4.2 Components of IWRMD Plans 30
* 2.5 Consult Guidelines for Preparation of Water Safety Plans - Resilient to Climate Change 30
* 2.6 Environmental and Social Impact Assessment Compliance 30
* 2.6.1 Procedures for Conducting ESIA in Tanzania 31
* 2.6.2 Strategic Environmental and Social Assessment (SESA) Compliance 31
* 2.7 Potential Impacts of Climate Change on Water Supply Projects 32
* 2.8 Participation of Community Based Water Supply Organizations (CBWSO) in Various Planning Stages 32
* 2.9 References 32
* CHAPTER THREE 35
* WATER SOURCES ANALYSIS 35
* 3.1 Availability of Water Resources in Tanzania Mainland 35
* 3.2 Water Sources Available in Tanzania Mainland 38
* 3.2.1 Rainwater and fog harvesting 39
* 3.2.2 Surface Water 39
* 3.2.2.1 Rivers or streams 39
* 3.2.2.2 Impoundments 39
* 3.2.2.3 Springs 39
* 3.2.2.4 Lakes 39
* 3.2.2.5 Dams 40
* 3.2.3 Groundwater 40
* 3.2.3.1 Infiltration galleries/wells 40
* 3.2.3.2 Well 40
* 3.2.3.3 Classification of wells based on the aquifer tapped 41
* 3.2.3.3.1 Shallow wells 41
* 3.2.3.3.2 Deep wells 41
* 3.2.3.3.3 Artesian wells 41
* 3.3 Quality Suitability of Water Sources for Water Supply Projects 42
* 3.4 Pilot Testing of Water Sources for Establishment of Appropriate Treatment 42
* 3.5 General Considerations for Selection of Water Sources 42
* 3.5.1 Adequacy and reliability 42
* 3.5.2 Quality of water sources 43
* 3.5.3 Technical Requirements 43
* 3.5.4 Cost implications to develop a water source 43
* 3.5.5 Protection of water sources 43
* 3.5.6 Legal and management requirements 44
* 3.5.7 Distance of water supply source 44
* 3.5.8 Topography of the project area and its surroundings 44
* 3.5.9 Elevation of a source of water supply 44
* 3.6 Determination of water source yield 44
* 3.6.1 Rainwater and fog harvesting 45
* 3.6.1.1 Rainwater harvesting 45
* 3.6.1.1.1 Types of rainwater harvesting 45
* 3.6.1.1.2 Components of rainwater harvesting system 46
* 3.6.1.1.3 Estimation of the yield 47
* 3.6.2 Hydrological Analysis of Surface Waters 47
* 3.7 Other considerations for various water sources 55
* 3.7.1 Water permits Considerations 55
* 3.7.2 Conservation of water sources 55
* 3.8 References 55
* CHAPTER FOUR 56
* WATER DEMAND ASSESSMENT 56
* 4.1 Water Demand Assessment 56
* 4.2 General Factors Affecting Water Demand Assessment 57
* 4.3 Determination of Water Demand for Different Uses 58
* Step 7. Establish Net Water Demand 67
* Step 9: Establish Operational water consumption 67
* Step 10: Establish System water losses 68
* Step 11 Establish Non-Revenue Water 69
* 4.4 Variations in Water Consumption 70
* 4.4.1 Definitions 70
* 4.4.2 Variation in the Rate of Consumption 71
* 4.4.2.1 Diurnal variation in demand 71
* 4.4.3 Peak Factors 72
* 4.4.4 Predicting Demand 74
* 4.4.5 Design Demand 75
* 4.5 References 75
* CHAPTER FIVE 76
* PIPELINES DESIGN 76
* 5.1 Design Requirements of pipelines 76
* 5.2 Types of pipelines 76
* 5.3 Security considerations for pipelines 76
* 5.3.1 Methods of water transmission and distribution 76
* 5.3.2 Gravity flow 77
* 5.3.3 Pumping with storage 77
* 5.3.4 Direct pumping to the distribution system 77
* 5.4 Pipeline Hydraulics Assessment 77
* 5.4.1 Pressure 77
* 5.4.2 Determination of Head Losses 77
* 5.5 Water supply transmission system 79
* 5.5.1 Determination of Transmission Pipe Size 79
* 5.5.2 Maximum Pressure 79
* 5.6 Distribution system 80
* 5.6.1 Branched System 80
* 5.6.2 Looped System 81
* 5.7 Pipe network analysis 82
* 5.7.1 Network analysis by Conventional method (Hardy Cross) 82
* 5.7.2 Network Analysis by Computer Software 82
* 5.7.2.1 EPANET Software 82
* 5.7.3 Pipeline design criteria 85
* 5.8 Pipeline materials selection 86
* 5.8.1 Considerations in Selecting Pipeline Materials 86
* 5.8.1.1 Flow Characteristics 86
* 5.8.1.2 Pipe Strength 86
* 5.8.1.3 Durability 87
* 5.8.1.4 Type of Soil 87
* 5.8.1.5 Availability 87
* 5.8.1.6 Cost of Pipes 87
* 5.8.2 Types of Pipe Materials Available 87
* 5.8.2.1 Galvanized Iron (GI) Pipes 87
* 5.8.2.2 Plastic Pipes 87
* 5.9 Appurtenances for transmission and distribution mains 88
* 5.9.1 Valves 89
* 5.9.1.1 Isolation Valves 89
* 5.9.1.2 Check Valves 89
* 5.9.1.3 Float Valves 89
* 5.9.1.4 Air Release Valves 89
* 5.9.1.5 Pressure Reducing Valves 89
* 5.9.1.6 Washout valves 89
* 5.9.2 Fittings 89
* 5.10 References 90
* CHAPTER SIX 91
* PUMPING SYSTEMS 91
* 6.1 Introduction 91
* 6.2 Rationale 91
* 6.3 Common Types of Pumps used in water supply 91
* 6.4 Pumping System Setup 91
* 6.5 Source of Pumping Power 92
* 6.6 Pumping system design pump selection 92
* 6.7 Pump Protection 95
* 6.8 References 95
* CHAPTER SEVEN 96
* WATER TREATMENT 96
* 7.1 Introduction 96
* 7.1.1 Classification of the qualities of water sources found in Tanzania according to the complexity of its treatment 96
* 7.1.2 Classification of Unit Operations to achieve water treatment levels 99
* 7.2 Recommended overall design approach for treatment plant components 99
* 7.3 Documents and websites consulted and those which are hyper-linked to the DCOM Manual 100
* 7.4 Water treatment design considerations 100
* 7.5 Water treatment levels and units 101
* 7.5.1 Pre-treatment 101
* 7.5.1.1 Scum and Floating Materials Skimmer 101
* 7.5.1.2 Screening or straining 101
* 7.5.1.3 Grit Removal 103
* 7.5.1.3.1 Design criteria 103
* 7.5.1.4 Sand Traps 105
* 7.5.1.5 Pre-chlorination 107
* 7.5.1.6 Water pre-conditioning (pH adjustment) 108
* 7.5.2 Primary Treatment 108
* 7.5.2.1 Sedimentation 108
* 7.5.2.2 Primary Filtration 114
* 7.5.2.2.1 Slow Sand Filtration 114
* 7.5.2.2.2 Rapid Gravity Sand Filtration 117
* 7.5.2.2.3 Comparison between Slow Sand Filters and Rapid Sand Filters 118
* 7.5.2.2.4 Other Types of Filters 119
* 7.5.2.3 Floatation 124
* 7.5.2.3.1 Dissolved-Air Floatation 124
* 7.5.2.3.2 Electrolytic Floatation 125
* 7.5.2.3.3 Dispersed-Air Floatation 125
* 7.5.2.4 Aeration 125
* 7.5.2.4.1 Falling Water Aerators 126
* 7.5.2.4.2 Spray Aerators 127
* 7.5.3 Secondary Treatment 130
* 7.5.3.1 Clarification 130
* 7.5.3.2 Coagulation 130
* 7.5.3.3 Flocculation 131
* 7.5.3.4 Filtration 131
* 7.5.4 Tertiary Treatment 132
* 7.5.4.1 Disinfection 132
* 7.5.4.1.1 Disinfection Methods 132
* 7.5.4.1.2 Chlorinators 132
* 7.5.4.1.3 Design considerations for chlorinators 133
* 7.5.4.2 Ozonation 133
* 7.5.4.3 Water softening 134
* 7.5.4.3.1 Methods of Softening 135
* 7.5.4.4 Defluoridation of Water 139
* 7.5.4.4.1 Fluorides 139
* 7.5.4.4.2 Defluoridation 139
* 7.5.4.5 Water Conditioning 141
* 7.5.5 Management of Water Treatment Sludge 141
* 7.5.5.1 Treatment of Water Treatment Sludge 141
* 7.5.5.1.1 Sludge Thickening 141
* 7.5.5.1.2 Sludge Dewatering 143
* 7.5.5.1.3 Sludge Drying Beds 144
* 7.5.5.1.4 Sludge Lagoons 144
* 7.5.5.1.5 Mechanical Sludge Dewatering 145
* 7.5.5.1.6 Backwash Water Recovery 145
* 7.5.5.1.7 Waste from Slow Sand Filters 146
* 7.5.5.2 Disposal of sludge 147
* 7.6 References 147
* CHAPTER EIGHT 148
* TREATMENT OF WATERS WITH SPECIAL CONTAMINANTS 148
* 8.1 Natural Organic Matter 148
* 8.2 Arsenic 149
* 8.3 Radioactive 149
* 8.4 Fluoride removal from drinking water 149
* 8.5 Toxic Cyanobacteria in Drinking Water 150
* 8.6 Available methods for removal of special water contaminants 152
* 8.7 Desalination 152
* 8.7.1 Additive method 152
* 8.7.2 Adsorption methods 153
* 8.7.3 Capacitive deionization (CDI) 153
* 8.7.4 Membrane Filtration 154
* 8.7.5 Reverse Osmosis 156
* 8.8 References 158
* CHAPTER NINE 159
* DESIGN OF WATER STRUCTURES 159
* 9.1 Sizing and Locating Water Structures 159
* 9.1.1 Tanks 159
* 9.1.1.1 Storage tanks 159
* 9.1.1.2 Sedimentation/Settling Tanks 160
* 9.1.1.3 Break Pressure Tanks 161
* 9.1.2 Water Intakes 162
* 9.1.3 Dams 164
* 9.1.3.1 Engineering Classification of Dams 164
* 9.1.3.2 Size classification of dams 164
* 9.1.3.3 Feasibility and geotechnical investigations 166
* 9.1.3.4 Hydrological analysis of the catchment 167
* 9.1.4 Geotechnical Investigation 169
* 9.1.4.1 Design of dams 170
* 9.1.5 Boreholes 173
* 9.1.5.1 Groundwater prospecting 179
* 9.1.5.2 Drilling 182
* 9.1.5.3 Siting of Well/Borehole 182
* 9.1.5.4 Well design 183
* 9.1.5.5 Pumping Tests 183
* 9.1.5.6 Groundwater quality 187
* 9.1.6 Water points and Service connections 190
* 9.1.7 Common Types of Water Points 191
* 9.1.8 Minimum Technical Requirements of Water Points 191
* 9.1.9 Criteria for Design of Water Point/Kiosks 191
* 9.1.10 Location Considerations for Water Points 192
* 9.1.11 Technical Tips to Improve Water Points 193
* 9.1.11.1 Rainwater harvesting 196
* 9.1.11.2 Fog harvesting 200
* 9.2 Structural Design of Concrete 201
* 9.2.1 Structural requirements 201
* 9.2.2 Methods 201
* 9.2.2.1 Working Stress Method 201
* 9.2.2.2 Ultimate Load Method 201
* 9.2.2.3 Limit State Method 201
* 9.3 References 201
* CHAPTER TEN 203
* APPLICATION SOFTWARE 203
* 10.1 Application Software Contexts 203
* 10.2 Recommended Application Software 203
* 10.2.1 Distribution Network Design Software 203
* 10.2.1.1 Epanet 203
* 10.2.1.2 AutoCAD 204
* 10.2.1.3 WaterCAD 204
* 10.2.1.4 WaterGEMS 204
* 10.2.1.5 KY PIPES 204
* 10.2.1.6 GeoNode 204
* 10.2.1.7 AutoStudio 204
* 10.2.1.8 InfoWater 205
* 10.2.1.9 GIS Software 205
* 10.2.1.10 MS Project 205
* 10.2.2 Operation and Maintenance Software 205
* 10.2.2.1 MS Project 205
* 10.2.2.2 Excel 205
* 10.2.2.3 EDAMS 206
* 10.2.3 Water Quality 206
* 10.2.3.1 WaterCAD 206
* 10.3 Supervisory, Control and Data Acquisition (SCADA) Systems 206
* 10.4 References 207
* CHAPTER ELEVEN 208
* METERING 208
* 11.1 Introduction 208
* 11.2 Types of Water Meters 208
* 11.3 Prepaid Meters 208
* 11.4 Types of Prepaid water models commonly used in Tanzania 209
* 11.5 Importance of Prepaid Water Metering 210
* 11.6 Design Considerations for Prepaid Water Meters 210
* 11.7 Design considerations for prepaid public standpipes 211
* 11.8 Design consideration for individual domestic customer 212
* 11.9 Design consideration for Commercial and Institutional Customers 212
* 11.10 Importance of integrating Prepaid with Post paid revenue management 212
* 11.11 Selection Criteria for Prepaid water meters 212
* 11.12 References 214
* 11.13 Internet Links: 216
* CHAPTER TWELVE 217
* DESIGN STANDARDS AND SPECIFICATIONS 217
* 12.1 Design Standards 217
* 12.2 Specifications 218
* 12.3 Materials 218
* 12.3.1 Building Materials 218
* 12.3.2 Materials Testing 219
* 12.3.2.1 Aggregates 219
* 12.3.2.2 Water 221
* 12.3.2.3 Cement 221
* 12.3.2.4 Concrete Works 221
* 12.3.2.5 Steel 222
* 12.4 Soil Test 222
* 12.4.1 Methodology of conducting Soil Investigation for borehole and test pit 222
* 12.4.2 Soil Investigation for dams 223
* 12.4.3 Suitability of soil materials for dam construction 223
* 12.4.4 Determination of In-Situ Bearing Capacity of the Soil 224
* 12.5 References: 227
* CHAPTER THIRTEEN 228
* ROLE OF STAKEHOLDERS IN DESIGN OF WATER SUPPLY PROJECTS 228
* 13.1 Types of Stakeholders 228
* 13.2 Roles of stakeholders 228
* 13.3 References 230
* APPENDIX A: CLIMATE CHANGE AND RESILIENCE TO CLIMATE CHANGE 232
* APPENDIX B: MINIMUM WATER FLOW REQUIREMENT FOR FIRE FIGHTING 237
* APPENDIX C: EXAMPLE: ESTIMATING THE CAPACITY OF TANK 239
* APPENDIX D: STRUCTURAL DESIGN OF CONCRETE 241
* APPENDIX E: SUPPLY PUMPING SYSTEMS 251
* APPENDIX F: SOURCE OF PUMPING POWER 263
* APPENDIX G: ADDITIONAL DETAILS OF VARIOUS UNIT OPRATIONS 275
* APPENDIX H: METHODS FOR DISINFECTING WATER 281
* APPENDIX I: MEASUREMENTS OF WATER HARDNESS 287
* APPENDIX J: BASIC STATISTICS USED IN ESTIMATION OF DESIGN OF FLOOD EVENTS 289
* APPENDIX K: DAMS DETAIL DESIGN 294
* APPENDIX L: STANDARD DRAWINGS 306
* APPENDIX M: SELECTED INTAKE DESIGNS. 307
* SUBJECT INDEX 309
*