Using Regional Ground‐Water Model in Water Resource Planning

Abstract

Nassau County, New York is presently developing a water management plan. In addressing the fundamental question of the ability of the aquifer to yield sufficient quantities of water for public supply, two approaches have been used. The first is hydrograph analysis of water levels over a 45‐year period. The second approach involves using a three‐dimensional, finite element ground‐water model. Results include an analysis of the aquifer response to the stress of increased consumption and severe drought. Water balances are developed for each aquifer under predevelopment and present conditions. The technical analysis concludes that the aquifer can yield sufficient quantities of water, but present consumption also means diminished streamflow and potential salt‐water intrusion. The paper also highlights how various planning perespectives affect the interpretation of the technical analysis. Purely technical information is not sufficient to reach a consensus on water issues. Education of the public and other participating agencies, as well as consensus‐building techniques and public relations, are needed to develop an effective plan.