Further water resource development is often avoidable through efficiency improvements in water delivery and use. Therefore, efficiency improvements should be given a clear priority over new source development in water supply planning as the preferred alternative for closing a current or potential gap between water demands and existing supplies. This essay discusses the reasons supporting such a preference, including cost savings, energy savings, water quality benefits and increased protection of water levels needed to maintain the integrity of fisheries and other water-dependent organisms and ecosystems. A major objective of water supply planning is to help communities avoid current or potential water shortages. Withdrawals, diversions and other artificially-induced reductions in water levels in rivers, streams, kettle ponds, wetlands and other hydric ecosystems have the potential for causing serious ecological damage, especially during drought periods.
Water is an essential component of aquatic and other water-dependent ecosystems such as wetlands.
The presence of water in sufficient amounts and periods of time is crucial to the continued survival of many plants and animals in these areas. Removal of water from these areas can cause significant environmental damage, depending upon the time, location and amount of the withdrawal and the sensitivity of the affected areas. Most of these species have evolved to withstand a certain level of stress resulting from naturally-occurring drought periods. Water withdrawals and diversions for water supply or other purposes, however, can significantly increase the duration, frequency and severity of drought conditions. This problem is further aggravated by the fact that new diversions or withdrawal points are often proposed to be located within the shrinking inventory of relatively unspoiled and uncontaminated areas which possess high ecological values and sensitivities.