Changes

Large diameter wells and smaller diameter boreholes can be used to directly recharge or dilute shallow aquifers where low permeability strata (rock) overlies the aquifers and where other infiltration methods are not effective. The important thing is that water of high enough water quality is used for this purpose. Although this method of recharge is practised with deep and high-yielding boreholes, this technique mainly describes recharge at the family level in areas where hand dug wells run dry at the end of the dry season or where groundwater is saline.

In loosely consolidated material, recharge pits and trenches are also used in cases where low permeability material overlies the aquifer, which occurs at trench-able depth, approximately 5-15m. Structures are excavated sufficiently deep to penetrate the low permeability strata, in order to provide direct access to the aquifer. Trenches or pits can be build to maximise the side-wall surface area and minimise the bottom surface area in order to facilitate horizontal movement of recharge water into the aquifer. The facilities should ideally be covered to keep out sunlight, animals, and people.