INTRODUCING INNOVATIVE RAINWATER HARVESTING TECHNOLOGIES TO IMPROVE ACCESS TO SAFE WATER IN BORENA ZONE Dr Ing. Alemayehu Haddis (Associate Professor) Dr Ing. Esayas Alemayehu (Associate Professor)
PROJECT INCEPTION Campaign to drought stricken areas in Western Hararge (DTTP supported by Carter centre) in 2004 - Observation of rainwater catchment in farm plots was intensified by the ministry of Agriculture We learnt that: - The ponds have become potential sites for Malaria vector propagation - There was intensive evaporation and the ponds last only few days - The quality of water was so poor (muddy)
Some of the open ponds in Eastern Ethiopia
Quick evaporation and crack in the base of open ponds
PROJECT INCEPTION (CONTINUED) Farmers were highly disappointed because it could not compensate the labour and other investments. Critical thinking: How could we best use this technology? What can we do to influence policy? - Looking at the hydrological information (ground water table, dry river catchment basins and rainfall), the idea of rainwater harvesting was not a bad idea.
THE DIF CALL - OPPORTUNITY TO PILOT STUDY GENERAL INFORMATION Project Title: Development of innovative technologies for the control of Malaria transmission in rain water harvesting Level 1 Reference code JU7.1/L.2/G/H/05R1 Project performance agreement signed – July 7, 2005 Total allocated money for the project – ETB 171 486.00 Official launching of the project – October 7, 2005 Amount of money utilized – about 98.8% of the allocated budget Status of this progress report – Final.
DESIGN OBJECTIVES The overall objective of the project was to develop and test a local technology for rainwater harvesting in rural communities to improve access to safe water for domestic purposes 4 basic principles of design were introduced. 1. Catchment collection should be > 70% 2. The media used should assist in water purification/ filtration 3. Evaporation should be minimized 4. The system should be mosquito proofed
MAJOR PROJECT ACTIVITIES Activity 1 – Literature survey and development of 3 alternative designs The 3 designs considered were: A system with grass filters 1. A system with concrete 2. A system with plastic lining surface 3. A control in the natural catchment but without 4. lining and screening
MAJOR PROJECT ACTIVITIES (CONTINUED)
MAJOR PROJECT ACTIVITIES (CONTINUED) Activity 2 – Identification of sites for training and research → Serbo area (Babo PA was identified)
DISCUSSION WITH COMMUNITY MEMBERS
MAJOR PROJECT ACTIVITIES (CONTINUED) Activity 3 – Collection of environmental and climatic data Activity 4 - Selection of local filter material and grading it according to size and shape Activity 5 - Construction of rain water catchment basin
CONSTRUCTION
CONSTRUCTION
CONSTRUCTION
MAJOR PROJECT ACTIVITIES (CONTINUED) Activity 6 – Sampling (both from reservoir and the control ditch) for quality assessment. Activity 7 – Larval and Mosquito survey Activity 8 – Evaluation Activity 9 – Dissemination of project outcomes
Table 1. Evaluation of selected designs for rainwater harvesting Parameter PCT GCT CCT C Runoff coefficient 0.35 0.25 0.75 0.15 Catchment surface area (sq m) 72 100 35 120 Storage capacity (m 3 ) 20 20 20 20 Service length for one family 97 108 110 46 (days) Mosquioto larval count - 2 - > 20 Adult mosquitoes trapped - - - 5 Turbidity (NTU) 13 12 16 65 TDS (mg/L) 1800 1500 2000 >3000 Coliform count per 100 ml of 10 7 8 50 sample [1] The plastic sheet was found to be porous [2] The slope of the surface was 0.1 [3] Assumes 10L per capita per day (used only for drinking and cooking). They use other sources for cattle and to wash clothes including showers.
SCALING UP THE PROJECT IN BORENA ZONE
REFLECTION ON WATER SCARCITY IN BORENA Drinking water for humans and livestock is extremely scarce. There is no remaining surface water and levels in the traditional deep water cisterns ( Ellas ) are precariously low. Water rationing and tankering is in place for 30 kebeles in the low-land weredas. In many places poor quality drinking water is creating a health hazard; diarrhoea and other intestinal disorders are on the rise; Walter Eggenberger, Field Officer, UNDP-EUE (2011)
SIGNIFICANCE TO BORENA Water is scarce in the pastoralist community in Borena No surface water Ground water is too deep Opportunities Local knowledge is there - Local materials like sand available - Community understands the problem - Threats Shorter service period (rapid evaporation, percolation) - Malaria - Poor quality of water -
WHAT WE INTEND TO DO Construct 2 rainwater harvesting systems in Arero woreda in Borena Zone 1 With grass filter and the other with synthetic liner as collection catchment. Total beneficiaries will be about 20 Households (only during the project phase) The four principles will strictly be applied with COST as a 5 th principle this time
OBJECTIVES General objectives To increase access to water and ensure food security through a piloted innovative rainwater harvesting technology in Borena. Specific objectives To describe the project site in terms of socio- economic, geo-hydrologic and climatic condition of Borena Zone in general and the project area (Arero) in particular.
SPECIFIC OBJECTIVES To identify locally available materials, current practices and local knowledge of the pastoralist community in Arero. To construct a total of 2 rainwater harvesting tanks having variable designs to collect rainwater from surface catchment. To evaluate the performance of the different systems. To produce learning notes, policy briefs and guidance manuals for use by field practitioners to scale up the technology to other areas of the pastoralist community.
METHODOLOGY Project site – Arero Design period: 3-4 months Design equation S = R x A x Cr S = Mean rainwater supply in m 3 (Storage tank capacity) R = Mean annual rainfall in mm/year A = Surface area of catchment in m 2 Cr = Run-off coefficient
Two RWH designs with control will be piloted The designs Design 1. Grass catchment surface followed by settling tank and then open water tight tanker with faucet. Design 2. Plastic (synthetic) catchment surface followed by settling tank which leads to rapid sand filter and then open water tight tanker with faucet.
5 DESIGN PRINCIPLES The runoff coefficient for both catchments should not be less than 0.7 The collection media should assist in water purification/ Filtration Evaporation and percolation should be minimal There should not be a chance for mosquitoes to come in contact and breed on the collected water surface. The cost must be cheaper than other systems previously used.
WHAT IS INNOVATIVE IN THIS PROJECT? Use local materials to prevent percolation and evaporation – Prevention of rapid water loss. It uses local filter material to improve the quality of rainwater It is designed to avoid multiplication of mosquitoes that transmit malaria disease It depends on rain water that is the ONLY reliable source in areas where ground water table is low and surface water does’nt exist.
SMALL INNOVATIONS CAN BRING A HUGE DIFFERENCE! THANK YOU
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