This system can be used both for small and big farms.
The improved surface irrigation equipment consists of a network of pipes (both underground and surface), flow meter, hydrants and finally a valve through which water flows in to the furrows.
The branch line is provided with a plastic valve for each furrow which can regulate the discharge.
Usually the branch line length is from 50 to 100meters. It can be made of PVC or PE with low resistance to the pressure.
Pump - diesel or electrical - can be used without any modifications.
It is recommended to set up a flowmeter and a valve in the main line of the network. The flowmeter is very important to know exactly the amount of water that you use to irrigate.
The water pass from the pump to fields through an underground network of pipes (1 meter deep) with low pressure. The network of pipes can be of PVC or PE pipes (diameter 200-250mm).
The hydrant regulates the flow of water through the network of pipes. Based on the slope of the field, and the area to be served, one can set up a hydrant every 50/100/150 meters.
From the hydrants water passes into the branch lines to be distributed in each furrow. The branch lines have a valve for each furrow to regulate the water discharge.
The principal operation and maintenance requirements include the need for regular cleaning of the system.
Ahar pynes should be built in areas which have high water table/recurring flood problem.
Ahars are reservoirs with embankments on three sides while pynes are diversion channels laid from the river or catchment area for impounding water in the Ahars.
Thus, an ahar resembles a rectangular catchment basin with only three embankments, and the fourth side left open for the drainage water to enter the catchment basin following the natural gradient of the area.
Water supply for an ahar comes either from natural drainage after rainfall (rainfed ahars) or through pynes where necessary diversion works are carried out.
Water for irrigation is drawn out by opening outlets made at different heights in the embankment.
Setting up Ahar pynes requires thorough assesment at the pre-construct stage. Geological investigations will need to be done for an assessment of the line of drainage and natural gradient of the area.
Appropriate regulatory mechanisms for water sharing need to be followed. Most common system of water distribution is that the water first goes to the upper reach field which is closest to the irrigation channel and then goes to the next field. As pynes served many villages, each village had its fixed turn of days and hours to have the water.
Community participation is needed for maintenance and upkeep of Ahar-pyne system. The routine upkeep work involves cleaning and desilting of ahar and pyne and maintaining the water conveyance network, while the system is in operation. Hence, these ordinary maintenance activities, such as the periodic clearance of silt, the repair of small branches of the ahars and field channels is taken up by the cultivators themselves.
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