1. Because both Taoyuan and Hukou irrigation areas have small watershed and the areas also lack groundwater, water resources should mainly come from the Ta-han river. The water resources from these areas themselves are limited. 2. Small irrigation reservoirs create many benefits on different aspects:(1) On the productive aspect: (a)farm irrigation,(b) aquaculture,(c) storage for water in industrial use.(2) On the human life aspect:(a)storage for water in domestic use,(b) recreation place for camping, barbecue, water skiing, boat sailing, fishing, swimming and so on,(c) beautification of the environment as a public garden,(d) fire pools.(3)On the ecological aspect:(a)runoff collecting,(b)storing the water in wet seasons and increasing the usage of surface water,(c)reducing the peak and disasters brought by the floods,(d)stabilizing groundwater level and restraining land subsidence,(e)groundwater recharge,(f)prevention of seawater intrusion,(g) providing the inhabitants for wild animals,(h) preservation of the ecological environment for wet land.3.The water quality has a great influence on the feasibility of the small reservoirs planned for multiple purposes.
