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==Suitable conditions==
{{Climate_change
|heading1=Drought
|text1='''Effects of drought''': Water quality deteriorates; Water levels in wells & boreholes reduce. <br>'''Underlying causes of effects''': Water levels reduce, which creates excessive algae and water plant growth due to water being too shallow; Less recharge to aquifers. <br>'''To increase resiliency of WASH system''': coming soon...
 
|heading2= Floods
|text2= 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 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.
- High cost of construction – in India, costs estimated at $5,000-10,000 for ponds that are 10,000-15,000m3 in volume. This is similar to other non-percolation ponds (see [[Natural ground catchment and Open water reservoir]] for details).
}}
 
==Resilience to changes in the environment==
====Drought====
'''Effects of drought''': Water quality deteriorates; Water levels in wells & boreholes reduce.
'''Underlying causes of effects''': Water levels reduce, which creates excessive algae and water plant growth due to water being too shallow; Less recharge to aquifers.
====Floods====
 
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.
==Construction, operations and maintenance==
Akvopedia-spade, administrator
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