Tanzania Ministry of Water Design Manual 4th Edition
Contents
Tanzania Ministry of Water Design Manual 4th Edition
Introduction
The existing design manual for water supply and wastewater disposal (3rdedition) was formally adopted by the Ministry that was responsible for Water in 2009 and it consists of three parts namely; volume I on Water supply, volume II on Wastewater disposal and volume III on Water pipelines standards and specifications. Since it is now nearly ten years since the third edition of the design manual was adopted and in the meantime, many scientific and technological changes have taken place including the conclusion of MDGs and adoption of the SDGs in 2015 as well as learning some useful lessons out of implementation of the WSDP I and WSDP II (which is still ongoing); it is felt it is high time to revise the design manual.
Volume I: Guidelines for Design of Water Supply and Sanitation Projects
Table of Contents
1. Introduction 2. Genesis/Background 3. Rationale 4. Organisation/description of the manual 5. ESIA and EIA Compliance 6. Water supply 6.1 Community and CBWSO participation in planning 6.2 Water resources, water sources (impoundments, GW-shallow & deep wells, rivers, springs, lakes, dams, charcoal dams, RWH), Water quality, Pilot testing for water treatment, GW recharge systems 6.3 Demand assessment (current and future, and methodologies: per capita demands; peak/loss factors; demand sectors & their projections; evolution of rural water consumption) 6.4 Water quality criteria and standards (TBS, WHO guidelines) 6.5 Design of Infrastructure: intakes, rising main pipelines, break pressure tanks, washout & air release values, various different valves, storage tanks, distribution pipelines, water points & soak pits 6.5.1 Design of water supply networks 6.5.1 Types of networks (e.g. grid, loops, etc.) 6.5.2 Design methodologies 6.5.2.1 Transmission main 6.5.2.2 Distribution network 6.5.2.3 Storage tanks 6.5.3 Units costs 6.6 Gravity schemes 6.7 Pumping systems 6.7.1 Type of pumps: (electromechanical, submersible, floating etc.) 6.7.2 Source of pumping power (diesel, hydraulic rams, solar, wind etc.) Solar without battery for pumping Solar with battery for lighting not for pumping water 6.8 Residual heads at different points 6.9 Water treatment 6.9.1 Recommended water quality investigation prior to suitable treatment 6.9.2 Selection of optimal water treatment for different water sources 6.9.3 Water disinfection 6.9.3.1 Pre- and post- chlorination, Residual chlorine. 6.9.3.2 Solar, UV, ozone disinfection, etc. 6.9.4 Matrices of recommended flow sheets for different treatments (RO, nanotechnology, filters, sedimentation, aeration, flocculation, coagulation, etc.) 6.10 Dams 6.10.1 Feasibility, location assessment, soil tests, stability analysis, seepage analysis 6.10.2 Types of dams (Earth dams, concrete dams, charcoal dams, sand dams, etc.) 6.10.3 Design of dams 6.10.4 Water treatment 6.11 Groundwater 6.11.1 Feasibility for groundwater sources extraction 6.11.2 Groundwater prospecting (geophysical) 6.11.3 Tests wells 6.11.4 Aquifer tests (e.g. Pumping and drawdown tests, extents, recharge, groundwater quality tests) 6.11.5 Production wells 6.11.5.1 Acceptable borehole yield (Basis on the values and refer to PIM of 2006 WSDP II) 6.11.6 Well cover/capping 6.11.7 Groundwater monitoring-Observation wells 6.11.8 Groundwater treatment 6.11.9 Shallow Wells 6.11.10 Deep Wells/Boreholes 6.12 Rainwater harvesting 6.12.1 Rooftop water harvesting 6.12.2 Fog harvesting 6.12.3 Surface runoff harvesting 6.12.4 Water treatment 6.13 Application software 6.14 Supervisory, control and data acquisition systems 6.15 Prepaid metering 6.16 Water Kiosks 6.17 Safeguarding of water sources and infrastructure 7. Sanitation Management 7.1 Sanitation value chain (Capture, collection, storage, treatment, re-use, disposal; basis for estimation of wastewater generation based on water consumption and production processes) 7.2 Decentralized Wastewater Treatment Systems (DEWAT) Containment, Conveyance (Simplified Sewer, Solids-free Sewer, Conventional Gravity Sewer), Treatment (Preliminary Treatment, Primary Treatment , Secondary Treatment, Advanced Secondary Treatment, Treatment of Sludge from DEWATS), Disposal/Reuse (Treated Wastewater, Treated Sludge, Biogas), DEWATS Module Combinations 7.3 Sewage collection system 7.3.1 Cesspit Emptier/Vacuum trucks 7.3.2 Condominium Sewers (simplified) 7.3.3 Central Sewer
7.4 Treatment systems for sewage 7.4.1 Preliminary treatment (Screens, Grit chamber etc.) 7.4.2 Primary Treatment(septic tanks, primary sedimentation, Anaerobic pond, thickeners, roughing filters, inclined plate settlers etc. 7.4.3 Secondary treatment(septic tanks, UASB reactor, trickling filters, activated sludge systems, waste stabilization ponds and other biological treatment systems, constructed wetlands, inclined plate settlers 7.4.4 Tertiary Treatment (constructed wetlands, sludge dewatering beds, roughing filters 7.5 Design guidelines for on-site sanitation Setting treatment objectives based on the final end-use or disposal options, Estimating quantities and qualities (Q&Q) of incoming faecal sludge, Evaluating selection of management solutions and treatment technologies, Settling-thickening tanks, Unplanted drying beds, Planted drying beds, Co-composting, Co-treatment of faecal sludge with wastewater, Effluent treatment technologies 7.6 Design guidelines for faecal sludge management 7.7 Design guidelines for School WASH facilities 7.8 Design guidelines for Health care WASH facilities 7.9 Design guidelines/options for small towns or emerging towns 7.10 Sanitation by-products re-use as resources 7.11 Safeguarding of sanitation infrastructure 7.12 Application software 8. Design Specifications 8.1 Use of Standards 8.2 Materials 8.3 Earthworks(Soils analysis, etc.) 8.4 Concrete Works 8.5 Electromechanical Works 8.6 Pipe works –Fittings, Joints, etc 8.7 Manholes 8.8 As Built Documentation 9. Role of Stakeholders 10. Subject Index
