Tuesday, December 16, 2008
Water Resource Optimization using Canal Automation in Parambikulam Aliyar Project
The Parambikulam Aliyar Project ( P.A.P ) is a multipurpose and interstate river valley project, to divert the west flowing rivers to the East side to the then drought prone areas of the Coimbatore and Erode districts. The irrigation network consists of seven major lined canals, running for a total length of about 250 km. The lengths of the Branch Canals, Distributaries, and Minors are 244 km, 640 km, 1240 km respectively, through which about 4.25 lakhs acres of lands are being irrigated. This large irrigation network is managed using manually operated gates, and traditional techniques, which offers tremendous scope for water resource optimization using Canal Automation, which is a proven, cost effective solution for better and efficient water management.
In the 21st century, we are at a crucial juncture in the area of water management. Water managers need to develop creative and innovative solutions as well as develop holistic approaches to solve water crisis. There is always a focus on ‘Blue water’ or liquid water rather than on ‘Green water’ or vapour flow. Blue water constitutes only 10 percent of the total freshwater resource, which means that we are focusing only on the one-tenth of the resource base. A new water management approach that integrates blue and green water flows is the need of the hour.
At present in PAP irrigation network, water is distributed to farmers in set zoning patterns. Water managers take rainfall into account only when there is widespread rainfall throughout the entire ayacut. Even when rainfall is taken into account the water that is released is based upon thumb rules. Hence this may lead to farmers over irrigating their fields and subsequent drop in crop yields. But in order to produce “More crop per drop” and “More crop per unit farmland” an integrated water management strategy is required.
The aim of our project is to develop Net irrigation requirement (NIR) maps using rainfall maps and crop water requirement maps.
Based on the NIR maps the water that has to be released through any particular canal gate can be determined and the canal gates can be operated accordingly. This can be done practically only by adopting canal automation. Thus the water requirement of crops can be monitored real time and canal gates can be set to operate automatically as per the requirement.