The following information can be obtained through the operation system and water drawn from streams in Taoyuan Irrigation Association:
1.The surface water in Taoyuan and Hukou irrigation areas is fully exploited with the combination operation of drawing water from river diversion weirs, distributing water from main canals, and storing water in farm ponds.
2.Usually the water from river diversion weirs is drawn at the time of little precipitation. The correlation between water drawn from river diversion weirs and precipitation is low. Sometimes even when there is no precipitation, water is still drawn from river weirs. Therefore it can been seen that the use of return flow is very important for irrigation in Taoyuan area. Return flow includes urban sewage, farm drainage, and industrial discharge.
3.The water quality of the streams in Taoyuan area has been deteriorating and therefore the water diverted by river weirs is having poor quality. The way diverting water by river weirs will lose their original functions if the water quality is not to be improved.
4.Not only river water resources but also irrigation systems operated as a whole should be taken into account for a rational operation of diversion weir in Taoyuan and Hukou irrigation areas. The factors include the transporting and distributing ability of main canals, capability of farm ponds and so on.
5.Linear programming meets the demands in planning a rational operation of river diversion weirs in Taoyuan and Hukou irrigation areas. Other mathematical planning techniques are to be used when water quality is taken into account.
