2. INTEGRATED WATER RESOURCES MANAGEMENT PLAN
Overview
Water withdrawals, wastewater, and stormwater are the three major human impacts that significantly affect a watershed's hydrologic cycle, impacting water quantity and quality. An integrated water resources management plan (IWRMP) looks at water supply, wastewater, and stormwater together in order to “balance the water budget” and maintain water quality.
Water conservation and reuse is a major component of an effective IWRMP, and can help communities avoid costly infrastructure expansions. Communities should develop a water conservation plan that, at minimum, specifies conservation goals, profiles the water system, forecasts demand, and identifies conservation measures. Larger towns and cities, along with those located in “stressed basins” — watersheds suffering from more extreme low-flow conditions — should follow US Environmental Protection Agency (EPA) intermediate or advanced guidelines for water conservation planning, which include a more detailed implementation strategy and analysis of costs and benefits.
Drought and emergency management is another important component of an IWRMP. Each public water supplier should have a written plan to deal with emergencies, whether they are drought-related or man-made. A demand management plan that incorporates seasonal water use strategies enables water suppliers to address peak water use without putting excessive strain on the water supply and distribution system or on the environment.
Coordinated action among the different local boards that have jurisdiction over some aspect of local water resources management is a key to effective integrated planning. A local water resources task group that includes representatives of town departments such as water, public works, planning and zoning, and conservation can help overcome the fragmented nature of water resources management and achieve a comprehensive approach. The Massachusetts Department of Environmental Protection is currently updating its guidance to assist communities in developing IWRMPs.
Local Examples
In the Ipswich River watershed, approximately 80 percent of the water withdrawn is ultimately transferred out of the watershed, mostly as wastewater via sewer pipes. Infiltration of groundwater into sewer pipes, along with inflow of stormwater, adds to the net loss of water. Increased stormwater runoff short-circuits natural replenishment of groundwater aquifers, resulting in more extreme high and low streamflows. The loss of water in summer is made more extreme by higher evaporative losses, exacerbated by lawn watering. An integrated regional approach is needed to address and mitigate these imbalances in the water budget. The Ipswich River Watershed Management Plan identifies a comprehensive set of water supply, wastewater, and stormwater management measures to address the region's water deficit while accommodating projected growth.
The Regional Water Conservation Plan for the Ipswich River Watershed sets watershed-wide water conservation goals of 15 percent reduction in total system demand and 20 percent reduction in summer peak demand. The plan also identifies best management practices (BMPs) that communities should implement to achieve the goals. The ten BMPs are: develop a municipal water conservation plan in accordance with EPA guidelines; reduce unaccounted-for water; implement accurate demand forecasting; implement a pressure management program; conduct water audits; implement conservation pricing and billing systems; implement a comprehensive information and education program; offer a conservation technology implementation program (e.g., rebates and retrofits); reduce peak demand; and facilitate passage of municipal conservation bylaws and regulations. The Regional Water Conservation Plan for the Ipswich River Watershed was unanimously adopted by the Ipswich River Watershed Management Council, which includes water suppliers, state and municipal officials, environmental groups, and scientists.
At the municipal level, the town of Wilmington has developed a Comprehensive Water Resources Management Plan through the Massachusetts Environmental Policy Act (MEPA) process. The plan quantifies the water budget impacts of alternative water supplies and water conservation measures, as well as considering benefits of stormwater recharge in balancing the water budget. Reading has also developed a Local Water Resources Management Plan, in conjunction with the town's application for an interbasin transfer of water from the Massachusetts Water Resources Authority (MWRA).
Resources
Massachusetts Department of Environmental Protection, Guide to Comprehensive Wastewater Management Planning, 1996 (pdf) (Comprehensive revision anticipated in 2006)
Massachusetts Executive Office of Environmental Affairs, Ipswich River Watershed Action Plan, 2003 (pdf)
Metropolitan Area Planning Council, Once is Not Enough, 2005 (pdf)
Reading Local Water Resources Management Plan, Appendix D of Environmental Impact Report for Admission to the Massachusetts Water Resources Authority Waterworks System, Approved by the Water Resources Commission, December 2004 (On file at IRWA)
US Environmental Protection Agency, Water Conservation Plan Guidelines, 1998 (html)
Wilmington Final Comprehensive Water Resource Management Plan/Environmental Impact Report, 2004 (On file at IRWA)
Water Wise Communities: Index
- How Development Affects Water (link to IRWA site)
- Checklist: Is Your Community Water Wise?
- Water Wise Tools:
