NOTATIONAi,k = submatrix of partial derivatives of linearized equations on stage i with respect to variables on stage k (if i, k is omitted, i = i, and k = i -1)

A comparison between the fixed schedule of planned expansion of water supply sources and.an alternative expansion program based on a short-term decision from monitoring reservoir levels, water use, and streamflows and employing water reuse capacity and new source development is simulated for the Colorado Springs, Colorado, municipal water system. For this complex, fast growing system with supply based on streamflows and some current reuse capacity the alternative plan postpones major new development an average of 14 years at a cost at present value of half the original planned expansion.In many areas of the country, municipal water sys[ems are either renovating and reusing effluent to supplement present supplies or planning to incorporate reuse in the future.Municipal effluent has been reused predominantly for irrigation in Texas and California, and its use as a supplementary source ot • industrial, commercial, recreational, and residential water supply is still limited. A forthcoming Environmental Protection Agency report lists only 15 industrial, 3 recreational, and 1 residential application in the United States.

No abstract