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[[Image:InfiltrationBasin.jpg|thumb|right|200px| An infiltration basin in Omdel, Namibia. The aquifer provides water to the coastal towns of Walvis Bay, Swakopmund and Henties Bay, and a large open pit mine at Rössing.]]

The aquifer to be recharged needs to be at or near the surface. The base of the pond needs to be permeable. The typical amount of water going into the ground is 30 m/year for fine texture soils (e.g. sandy loams), 100 m/year for loamy soils and 300 m/year for coarse clean sands. A field method to determine seepage rates in the bottom of reservoirs has been developed which can be used to assist in design. Ideally infiltration rates should exceed evaporation rates.

====Drought====

'''Effects of drought''': Water quality deteriorates; Water levels in wells & boreholes reduce. <br>

Design pond capacity according to peak flood events, so it can handle the volume of water. Plant vegetation near the pond to stabilize soils, so that intense rainfall will not erode banks and/or create new escape channels.

The main issue is to minimize silting, as this will reduce infiltration capacity through the base and sides. There are several techniques to minimize this:

* Any diversion and intake structures should be made so as to minimize input of silt to the ponds. Sedimentation basins can reduce silt load before water enters infiltration pond. What might work better is to keep a good cover of indigenous grasses in the run-off area. Kambiti Farm in Kitui District provides a good example of previously degraded land being managed and where open dams did not silt up due to pasture management. Contour lines with trees or grasses in the runoff area also work. If the inflow channel is defined, silt traps can be tried out to reduce silt load as is done with Charco dams in Tanzania. In this case, stones laid across the channel form mini dams and perennial vegetation can be grown between these mini dams to reduce the flow velocity of water, thereby encouraging silt deposits.

De-silting will most probably need to be carried out at some stage. There may be more sustainable ways of doing this compared to the usual approach used in the recovery stage of DCM, where this process is often paid for by NGOs and where there is a lack of community will to contribute. Experience from infiltration ponds in India shows that securing participation is very difficult to achieve when users/farmers do not see any direct benefit from the ponds. An institutionally-resilient way to de-silt (or even construct) ponds may be to promote ponds on private land, where one landowner has a vested interest to maintain and de-silt the pond, thus reducing the need for NGO intervention in the longer run. Experience in India seems to support this where the farmer providing the land for the johad (pond) would be the prime beneficiary, of the recharged water on adjacent land, but where the community also benefited.

Percolation pond, capacity 10,000 - 15,000 m3 (India) US$ 5,000 - 15,000

Examples include dune infiltration ponds in South Africa, Tajamar ponds in Paraguay, and infiltration basins in Niger. Large dams can also be used to artificially recharge aquifers – in Jordan, one dam was constructed to recharge a well field 8km from the dam site, and experience from the past 6 years shows that groundwater levels have increased by 25-40 metres. In Nepal, small ponds traditionally helped to recharge spring water.

* [http://www.artificialrecharge.co.za/strategydocument/ARStrategySectB.pdf The Artificial Recharge Concept, its Application and Potential] Some examples from Africa, Europe, the Middle East, Australia and USA.

* [http://www.portlandoregon.gov/bes/article/127474 Vegetated infiltration basins.] Use plants to filter the water and control flooding.

* [http://www.samsamwater.com/library/Artificial_groundwater_recharge_for_water_supply_of_medium-size_communities_in_developing_countries.pdf ARTIFICIAL GROUNDWATER RECHARGE FOR WATER SUPPLY OF MEDIUM-SIZE COMMUNITIES IN DEVELOPING COUNTRIES.] or ([http://www.washdoc.info/docsearch/title/108685 alternative link]). E.H. Hofkes and J.T. Visscher. December, 1986.

* CARE Nederland, Desk Study: [[Resilient WASH systems in drought-prone areas]]. October 2010.