6. Other Relevant Data
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6. Other Relevant Data Market Centre Project 6-1 Evaluation of Water Sources for Market Centres 6-2 Water Quality Test (Existing Water Supply Facilities) 6-3 Social Condition Survey for Market Centres 6-4 Examination of Intake Pump 6-5 Hydraulic Calculation for Distribution Pipe Mchinji Rehabilitation Project 6-6 Borehole Survey 6-7 Water Quality Test 6-8 Borehole Condition Survey 6-9 Social Condition Survey for Mchinji Project 6-10 Borehole Rehabilitation and Construction Plan 6– 1 EVALUATION OF WATER SOURCE FOR THE MARKET CENTRES A6 - 1 - i TABLE OF CONTENTS 1. Outline of Survey ................................................................................................................................................ 1 2. Namitete/Chileka Market Centre ......................................................................................................................... 8 2.1 Source of Surface Water ................................................................................................................................ 8 (1) River flow fluctuation ................................................................................................................................ 8 (2) Water Quality ........................................................................................................................................... 11 (3) Water Rights ............................................................................................................................................. 14 2.2 Source of Groundwater ................................................................................................................................ 15 (1) Siting of Drilling Point for Test Boreholes .............................................................................................. 15 (2) Test borehole Drilling .............................................................................................................................. 20 (3) Pumping Test............................................................................................................................................ 22 (4) Water Quality Test .................................................................................................................................... 26 2.3 Evaluation of Water Source for Water Supply ............................................................................................. 27 3. Water Source for Mkanda Market Centre .......................................................................................................... 30 3.1 Source of Surface Water .............................................................................................................................. 30 (1) River Flow Fluctuation ............................................................................................................................ 30 (2) Water Quality ........................................................................................................................................... 33 (3) Water Rights ............................................................................................................................................. 36 3.2 Source of Groundwater ................................................................................................................................ 37 (1) Siting of Drilling Point for Test Borehole ................................................................................................ 37 (2) Drilling of Test Borehole ......................................................................................................................... 41 (3) Pumping Test............................................................................................................................................ 43 (4) Water Quality Test .................................................................................................................................. 49 3.3 Evaluation of Water Source for Water Supply ........................................................................................... 50 (1) Evaluation of Water Source ..................................................................................................................... 50 A6 - 1 - ii (2) Drawdown of Water Level by Mutual Interference ................................................................................. 50 (3) Discharge Compared with Planned Water Supply Amount ..................................................................... 50 4.Water Source for Santhe Market Centre ............................................................................................................. 52 4.1 Source of Surface Water .............................................................................................................................. 52 4.2 Groundwater Source .................................................................................................................................... 52 (1) Siting of Drilling Point for Test Borehole ................................................................................................ 52 (2) Drilling of Test Borehole ......................................................................................................................... 58 (3) Pumping Test............................................................................................................................................ 61 (4) Water Quality Test .................................................................................................................................... 67 4.3 Evaluation of Water Source for Water Supply ............................................................................................. 68 (1) Interference to Other Boreholes ............................................................................................................... 68 (2) Discharge Compared with Planned Water Supply Amount ..................................................................... 68 A6 - 1 - iii A6 - 1 - iv 1. Outline of Survey In order to evaluate the potential of candidate water sources for the water supply of market centres, which are targeted for the Project for Water Supply Systems for Santhe, Mkanda and Namitete/Chileka Market Centres, the survey team conducted the review of the past feasibility studies carried out in 1998, collection of existing data and field survey in each market centre. Targeted Market Centres; (1) Namitete/Chileka Market Centre, Lilongwe District (2) Mkanda Market Centre, Mchinji District, and (3) Santhe Market Centres, Kasungu District The contents of field survey are shown in Table A6-1-1. Table A6-1-1 Contents of Field Survey for Water Source Evaluation Contents of Field Survey Method Target Market Centres Survey Namitete/Chileka Mkanda Santhe River flow Data collection in Department of Water Resources 10 years for 2 stations Water Quality Entrusted to Central Water Laboratory, MoAIWD Liwelezi (including Physical /Chemical :4 samples Namitete River N/A River Agrochemicals) Microbial : 4 samples Surface Water Surface Water Water rights Collection of existing water rights listed in Water Resources Board, MoAIWD Selection of Area was recommended through consultation with drilling points MoAIWD and CRWB Points were decided after geo-electric survey done by the Survey Team 3 sites Test Boreholes PVC Casing 160mm Namitete 2 sites 3 sites (Additional) Depth : from 50m to 80m Chileka 1 site 3 sites Groundwater Pumping Test Step drawdown :4 steps Continuous Pumping :24 hrs. Recovery Test :2 hrs. Water Quality Test One sample each borehole A6 - 1 - 1 1.1 Surface Water Source (1) River flow data The hydrological observation points in Central Malawi under Department of Water Resources are shown in Table A6-1-2 and Fig. A6-1-1. In the target area three (3) observation points, which are the points of 5.E.1 on Namitete River and 5.F.2, 5.F.3 on Liwelezi River, are referred to the Project. Table A6-1-2 Hydrological Observation Stations on Namitete River and Liwelezi River Target Market Station Name of River Catchments Year Remarks Centres No. Station Name Area (km2) Observation Started Namitete/Chileka Namitete 5.E.1 Namitete 147 1953.11.17 town Stopped after starting 5.F.2 Mkanda Liwelezi - 1976.10.08 observation at 5.F.3 Mkanda Established at 5 km 5.F.3 Matumamba Liwelezi 278 1987.8.27 upper stream from 5.F.2 Matuwamba Sta. Namitete Sta. Source: NWDP (2003) Strengthening of the Water Resources Board, Ministry of Water Development, National Water Development Project Figure A6-1-1 Hydrological Observation Network in Central Malawi A6 - 1 - 2 (2) Water Quality Test Water Quality Test was carried out to find the physical/chemical characteristics with 19 parameters and microbial characteristics (Faecal Coliform , Faecal Streptococci). The numbers of the sample by water source are shown as below. Surface water 4 samples Groundwater 12 samples The sampling points for surface water quality test are shown in Table A6-1-3. Table A6-1-3 Sampling point for water quality test for surface water Target Market River Basin Sampling point Date of Sampling Remarks Centres Upper stream of bridge on M12 7th Oct. 2010 Station 5.E.1 Namitete/Chileka Namitete River Located between Kakuyu Dam 7th Oct. 2010 Namitete and Chileka Mkanda bridge 9th Oct. 2010 Station 5.F.2 Mkanda Liwelezi River Matuwamba village 9th Oct. 2010 Station 5.F.3 The tested parameters are shown in Table A6-1-4 and Table A6-1-5. Table A6-1-4