Experience in Denver, Colo.

Abstract

Figure 1 gives an idea of the geography of the collection system. Denver obtains its water supply from four different drainage basins located west and south of the city. Three of these basins are on the west side of the continental divide. The supply system includes five major reservoirs having about 500,000 acre-ft of storage and provides Denver with a safe yield of about 300,000 acre-ft/yr. The daily operation and the future expansion of this system present a number of problems for which computer applications are necessary. The supplysystem geography is such that the major supply is available to the south. The more limited supply enters the distribution system in the northwest part of the city. Therefore, part of the distribution problem is moving water from the south to the north through the system. Figure 2 gives an idea of the complexity of Denver's distribution system. The city is located in a valley with the mountains to the west and the high plateau of the plains on its east. The South Platte River runs through the city to the north. Treatment plants are located and sized in relation to availability of supply from the raw water system. There are currently three treatment plants in operation in the area: the Kassler Plant with the capacity of 50 mgd, the Marston Plant with a capacity of 260 mgd, and the Moffat Plant with a capacity of 150 mgd. A fourth plant is to be completed in 1977 and is designated as the Foot Hills Treatment Plant. It will have an initial capacity of 150 mgd and be expandable to 500 mgd. Plans are being developed to construct a reuse plant at the north edge of the city if and when feasibility and other problems can be worked out. The facilities shown with smaller circles are the major pumping stations and terminal reservoirs used to distribute water within the system. The largest pumping station on the system has a capability of pumping 120 mgd and is used to transport water from the Marston Treatment Plant to the south and east part of the city. The largest terminal reservoir has a capacity of 80 mil gal and is used to store water during off-peak hours from any of the three plants.