Artificial recharge and Rain water harvesting –Case studies in Kerala A.Subburaj,Scientist-D Central Ground Water Board Kerala Region,Trivandrum
Artificial recharge and Rain water harvesting –Case studies in Kerala
A.Subburaj,Scientist-D
Central Ground Water Board
Kerala Region,Trivandrum
Major causes for scarcity
• Rainfall pattern• Geomorphological set up• Drainage• Sand mining• Hydro geological factors• Over exploitation• Reclamation of land for settlement
Definition• Augmentation of ground water reservoir by man
made structures by using rain water.
• Rain Water Harvesting is deliberate collection and storage of rain water
Methods of Artificial Rechargea.Direct surface techniques
. Flooding
. Basins or percolation tanks
. Stream augmentation
. Ditch and furrow system
. Over irrigation
b.Direct subsurface techniques . Injection wells or Recharge wells
. Recharge pits and shafts
. Dug well recharge
. Bore hole flooding
. Natural openings,cavity filling
c.Combination of Surface-Subsurface techniques . Basin or percolation tanks with pit shaft or wells
d. Indirect Techniques . Induced recharge from surface water source
.Aquifer modification
Rain water Harvestinga.Storage of rain water on surface for future useb.Recharge to ground water- Pits- Trenches- Dug wells- Hand pumps- Recharge wells- Recharge shafts- Lateral shafts with bore wells- Spreading techniques
Benifits• An ideal solution to water problems in areas having
inadequate water resources• The ground water level will rise• Mitigates the effects of drought & achieves drought
proofings• Reduces the runoff which chokes the storm water drains• Flooding of roads and low land areas are reduces• Quality of water improves• Soil erosion will be reduced• Saving of energy per well for lifting of ground water-a one
meter rise in water level saves about 0.40 KWH of electricity.
CostS.No Recharge structure Approximate cost
(in Rs)
1 Recharge pit 2500-5000
2 Recharge trench 5000-10000
3 Recharge through hand pump
1500-2500
4 Recharge through dug well 5000-8000
5 Recharge well 50000-80000
Case studies