Why pump sea water onto your rice fields?
On a recent visit to Tra Vinh, I saw an unususual sight: next to the sea dike, which was built to prevent sea water intrusion, a farmer was pumping sea water back over the dike onto his rice fields. What was happening?
From 1998, the World Bank lent the government $68,000,000 to build the South Mang Thit sea dike and draining system in Tra Vinh Province. It was designed to stop sea water intrusion and thereby ensure the continued production of rice (and to a lesser extent fruits and vegetables). But 10 yers later, farmers behind the dike are still short of freshwater and rice productivity is very low and unstable. Because of their low incomes, farmers are increasingly interested in shrimp farming. And to farm shrimp they need sea water.
In the two villages I visited in My Long Nam Commune, although two sluice gates were open, more sea water was needed. So the government has built a third sluice gate at a cost of $750,000 to provide water to 190 hectares of shrimp ponds. “Farmers want to turn their rice field into shrimp ponds and they do so. The gorverment then has to support a new sluice gate to open up water flow for this area”, said an official from the Tra Vinh Department of Agriculture and Rural Development.
But even this third sluice gate doesn’t provide enough sea water and so in some areas farmers are operating their own pumps. Hence, the strange sight of the famer pumping sea water back over the dike, a reaction that calls into question the value of bulding expensive dikes to maintain production of low value rice when shrimp farming is a more attractive economic option. Of course, shrimp farming has its own environmental problems, but combined with mangroves, crabs, and fish, it can provide a diverse livelihood that is resilient to sea level rise and an increasingly salter environment . This experience indicates that central government should invest is supporting, not inadvertently preventing, this transition.
Ms. Nguyen Ngoc Anh - Project Manager - DANIDA funded MFF in Ben Tre and Tra Vinh Province