Sustainable Water Reallocation Planning for Semi-arid Parkland in Loess Plateau A case study of tianshui town

Rainwater catchment irrigation and municipal water supply are the current solutions for parkland water demand in townships of Loess Plateau. Rainwater catchment however, may lead to runoff imbalance or groundwater reduction, while the municipal water supply has priority for residential consumption and agricultural irrigation but not always for parkland. Thus, they are not favorable methods for parkland irrigation and may not guarantee parkland's water-consumption demand. Due to the reasons above, a new method of water supply adapted to the parkland in these semi-arid area townships should be proposed to decrease the pressure of rainwater catchment and municipal supply, and possibly reallocate available water resources. It should reduce the reliability of municipal supply and rainwater catchment for parkland water consumption, but utilize the drainage from residential area to aid the water demanding. Therefore, different reallocation plans can be made according to the factors such as evaporation, population, residential density, catchment capacity, parkland area, and vegetation in different towns. By utilizing green infrastructure and focusing on water reallocation through rainwater catchment and daily sewerage, multiple water reallocation plans can be adapted to the parkland and local habitats in townships in semi-arid area.