Size, Survey and Measurement

The main aim of watershed is to conserve rainwater in situ and made available to the crops. Therefore, it requires very careful management including identification of priority to the particular area, selection of site, survey, soil water conservation and tank or Water Lake (Talav).

Selection of Site

First select the site for water tank that can be built at the nala and then fixed the area of watershed. For this noted the places from which water has come and then fixed the circumference of the area. Area of watershed should be 100 hectare or smaller than 100 hectares when it is taken at village level.

Survey

After selection of site or area for watershed prepare contour map. From contour map watershed area is fix. Also it indicates slope, hills, and nala. It is also helpful for planning development work. Another map showing soil, depth, slope should be prepared. For watershed planning, these two maps are very essential.

Soil and Water Conservation

In watershed first decide which types of soil and water conservation works can be taken while going from hill to plain. Generally prepared for high slope bench terrace, medium slope and having sloped less than 3% bunding across the slope. If there is highly undulating or having high slope at the base, prepare terrace having to slow run off and water should end into the nala. After forming various bunds, provision for drainage into the nala should be prepared.

Water Lake

In Watershed area first select the site for water lake above the nala and then fixed the watershed area. It should be noted that is their sufficient water for lake, sufficient run off of water. Site of water lake should have no use for cultivation. Also there should be provision for run off of excess water. This lake helpful in increasing the water in the wells, and to bring the 20-30% land under irrigation.


Ag.
Technologies
(Agricultural
Engineering)