Download presentation
Presentation is loading. Please wait.
Published byMadison Manning Modified over 9 years ago
1
Sandy Elsworth Independent Consultant AJEWater.com
2
Sandy Elsworth ODI Groundwater, poverty and development 26 November 2014 Focus on groundwater Not on gw levels or CC impact on gw supplies in this short presentation Focus on boreholes and borehole management Experience in Ethiopia, Tanzania and Zimbabwe Each year 10,000 boreholes are drilled in Zimbabwe – funded through UNICEF predominantly
3
Sandy Elsworth 50% not working after 15 years
4
Sandy Elsworth ODI Groundwater, poverty and development 26 November 2014 Probably around 300,000 boreholes in country Of which around 100,000 no longer functional. Unicef has a programme commencing in December 2014 to address 7,400 problem boreholes However this is always seen in the context of a pump failure, not a borehole issue. Tender typically delivered by a drilling company – who simply want to drill new Lack of expertise and equipment to inspect and address borehole issue.
5
Sandy Elsworth ODI Groundwater, poverty and development 26 November 2014 Climate Change and WR Planning Issues paper published September 2014 GW serves 70% of the pop Recognised as critical in CC adaption “Yet its planning, development and management has received very little attention…” “…almost no monitoring of groundwater levels…”
6
Sandy Elsworth ODI Groundwater, poverty and development 26 November 2014 Addressing 3 core issues of gw management: 1. Inspect and remediate existing rather than drill 2. Proper testing programme 3. Long term monitoring and management
7
Sandy Elsworth ODI Groundwater, poverty and development 26 November 2014 Bulawayo is Zimbabwe’s 2 nd city Population 650,000 Water primarily supplied from 6 seasonal dams Cholera present in 2008 Average rainfall 590mm But Effective gw recharge Approx 3% of rainfall CC modelling suggests surface runoff Could be reduced to zero under Some scenarios
8
Sandy Elsworth ODI Groundwater, poverty and development 26 November 2014
9
Sandy Elsworth ODI Groundwater, poverty and development 26 November 2014 Historic Information search Internal Inspection of boreholes Fishing, air lifting, flushing, re-inspection Step test – at least 4 steps 60 minutes CRT – at least 1 day, up to 3 days 3 primary delivery mains to WTW. Use of hydraulic model (EPANET) Correct pump sizing for current, drought, operational variability, and CC conditions Training on site and in office
10
Sandy Elsworth Boreholes Inspection Units
11
Sandy Elsworth Test Pumping Equipment
12
Sandy Elsworth ODI Groundwater, poverty and development 26 November 2014
13
Sandy Elsworth ODI Groundwater, poverty and development 26 November 2014 Boreholes are abundantly distributed When a problem, the immediate response is typically: Drill another Train borehole operators and managers Regular water level measurements Protect headworks Inspect, clean, fish, remediate existing before redrill Invest in long term borehole and gw management – training, equipment, resources
Similar presentations
© 2024 SlidePlayer.com. Inc.
All rights reserved.