Run off rainwater harvesting
Practical Action
Figure 10: Outlet of the tank
Figure 11: Completed tank before plastering
Now plaster the tank completely with cement. In this case you should plaster the
outside of the tank about 15 cm above the ground level.
Figure 12: Plastering the tank
You would have observed an empty space of several inches, which has been left
around the tank during the construction, to facilitate the process of construction.
This empty space should be filled tightly with sand. Sand is used for the filling of
this space as it can be packed tightly and is not easily subjected to decomposition.
In the instance of repairs being needed for the tank, this sand layer will allow access
to the tank.
If maintained properly, it will be possible to use the rainwater-harvesting tank with
ease, for about 15 years.
Best practices of operation and maintenance
When the water in the tank becomes empty remove all soil deposits and other
waste products from the bottom of the tank and clean it well.
Figure 13: Run off rain water collection to the tank
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