Water Reuse Systems Analysis

Quantity-quality availabilities and requirements are part of the system description to be considered in the solution based upon an origin-destination matrix. When tertiary treatment and desalting plants and blending are included in the matrix, plant capacities can be obtained for any year of projected demand. Entries in the matrix must include the unit cost of delivering water having a specified quality from each origin to each destination; these costs include both transport and treatment costs. Least cost allocation solution is obtained by the transportation problem algorithm. The procedure was demonstrated by a cursory case study of the Salt Lake City region, an agro-urban-industrial area. Least cost results for 1965, 19890, 2000, and 2020 levels of demand showed a changing pattern of allocation. For 1965 demand levels surface and groundwater supplies were sent directly to municipal and agricultural uses, with effluents to system outflow. By 1980 tertiary treatment enters the picture and by 2020 desalting becomes important. For 2020 all surface and groundwater goes to blending to combine with output from tertiary treatment and desalting plants.