Optimal installation policies of additional water supply facilities for a growing population

This paper considers the problem of installation of additional facilities in water supply system to meet the demands of an increasing population. Dynamic programming has been used to minimize a performance index based on the waiting cost of the population needing water supply, and cost of unutilized capacity. These two costs will ensure the proper size of additional facilities to be installed at a particular time. Assuming that water requirement over a certain time period in future has been estimated, optimal installation times of additional facilities in water supply system and optimal number of such installations over the given time period have been determined. Though the present model does not involve the installation cost explicitly, it is inherently present in form of cost of unutilized capacity and optimal number of installations.