A thesis submitted in partial fulfillments of the requirements for the degree of Master of Engineering, School of Civil Engineering

Thesis (M. Eng.) - Asian Institute of Technology, 1994

Small land resource per capita, in the Red River Delta, urges the increase in land utility and crop yield. At the same time the change in economic policy of the country increases off-farm job opportunities which insist farmers saving their labor from farming works. These are together to require an adequate irrigation, drainage and farm conditions. The evaluation, in this study, of a typical irrigation project shows that though the irrigation and drainage facilities have been developed for over thirty years, the ill-controlled water condition at farm-level is still widely seen. It is much more significant in the downstream areas and less in the upstream areas. Accompanying is the variation in farm conditions among the areas inside the command area. The ill-conditions of the irrigation, drainage and farms results in the reduction estimated at around 60% and 70% of rice yields in the spring crop season and in the summer crop season, respectively, for the most significant cases. Meanwhile, the resulted increase in labor input to a spring rice crop is found more than 100% for the most significant case. The findings also shows that the potential increase of the total cultivated area can be 40% on average. The combination of irrigation and drainage improvement and land consolidation is recommended as a measure to increase rice yield, to expand cultivated area by the means of increasing upland crop cultivation, and to reduce labor requirement for rice cultivation, in the Red River Delta.