Actual water consumption and water management in paddy field -Referring to the Thailand gravity irrigation district (2)-

In the Thailand gravity irrigation district, we surveyed consumptive water use and water management actual condition of the paddy field. It is anticipated that the water management of farm land consolidation district and non farm land consolidation district differs. Therefore, the survey was carried out in both districts. To begin with, 20 plots was respectively selected in each district, and stake for the water level measurement was installed. The water level was measured in a day one time fixed time. Consumptive water use in a day is obtained as a water level difference in continued two days without inflow and runoff. As a result of the measurement, it was 11 mm/d regardless of the degree of farm land consolidation throughout one year. And, operating ponding depth was about 80 mm, and the highest ponding depth was about 150 mm. These results become the data which is very precious for future water demand calculation.