12. WATER BANK / WATER DEMAND MITIGATION PROGRAM
Overview
The term “water bank” means different things to different people in different parts of the United States. In the western states, water banks are typically systems of valuing, trading, buying or selling water rights. In Massachusetts, the concept is evolving to mean a system of accounting and paying for measures that offset or mitigate water losses due to water withdrawals, sewering, and/or increased impervious areas that prevent aquifer recharge. The primary goal of a water demand mitigation program program is to “balance the water budget” by reducing water losses and keeping water local so that it is recharged within the same watershed from which it is drawn. The Massachusetts Water Resources Commission and the Massachusetts Department of Environmental Protection are currently considering definitions and guidelines for water banks and mitigation programs.
Water banks often set an offset or mitigation ratio. For example, a 2:1 ratio indicates that for every gallon of “new” water demand due to construction, expansion, or change in use or processes, the water bank would require two gallons of “new” water savings, retention, reuse or aquifer recharge. A water bank is a broad concept that may incorporate not only water conservation measures to offset new demand, but also other measures such as sewer fees charged to reduce infiltration and inflow, stormwater utilities focused on reducing runoff and increasing groundwater recharge, and reuse or recharge of treated water to groundwater. A spreadsheet-based accounting system tracks water losses and “gains” and the net balance.
Water banks and water demand mitigation programs may be funded through a variety of mechanisms. One approach is to charge a fee at the time of application for a building permit, based on the estimated daily water use according to Title 5 guidelines for septic systems. Another approach is to charge a per-gallon fee to all water users in the service area. The fee should be established based on empirical methods to establish the actual costs of saving, recharging or reusing water.
Local Examples
The town of Weymouth, located south of Boston, has a water bank program that requires a water use permit for new or increased water use and includes the option of paying a water conservation mitigation fee. The Weymouth water bank program requires that projected water demand from new development or expansions be offset by water savings. New demand is based on wastewater flow estimates under Title 5, 314 CMR 7.15. Weymouth requires that two gallons be saved for every one gallon of projected new or increased water demand. A contractor or developer has the option of either retrofitting an older home or business with water saving devices (or in the case of businesses, modifying water use practices and processes to achieve the required savings), or paying a $10 per gallon fee that goes into a dedicated fund, which the town uses to implement mitigation projects. Weymouth has a separate “sewer bank,” charging an additional $10.00 per gallon to remove infiltration and inflow from its sewer system, at a required ratio of 6:1. It also charges a $7 per gallon administrative fee; thus the total fees are $27 per gallon.
The water bank mitigation fee is based on the per gallon cost of performing the retrofit program plus administrative costs. To date, projects have involved retrofitting of older homes and public buildings with water saving devices, installation of rain sensors on automatic irrigation systems, public education, and leak detection and repair in the water distribution system. Weymouth reports that the water bank enabled the town to save 1.2 million gallons of water per day in 2003. Mitigation fees, which go into a dedicated Water Conservation Fund, totaled about $200,000 in 2003. The water bank program has not had a negative impact on new development, which remains robust in Weymouth. According to the town, the mitigation fee program “has allowed the town to implement an aggressive water conservation program, and accommodate new growth and water demand.”
A water demand offset program has also been instituted by Abington Rockland Joint Water Works. The Water Works had a program whereby any person proposing development with increased water demand was required to implement water savings of two gallons for every one gallon of new water demand. Developers were required to do specific retrofits, such as providing low-flow showerheads and faucet aerators to existing properties. In February of 2004, because the Board of Water Commissioners felt that the retrofit program had “run its course,” the program was changed to impose a one-time fee of $5.50 per gallon of proposed daily water use, based on Title V guidelines. The fee applies to all types of development (including G.L. c. 40B housing) and is collected at the time of application for a building permit. The fees are being used to fund a new water storage tank. The authority for this program is through the rules and regulations of the Water Work’s Board of Water Commissioners.
As of 2006, Danvers is implementing an innovative “Water Usage Mitigation Program,” which requires that new developments utilize the most efficient fixtures and appliances, as well as pay a mitigation fee to fund water efficiency improvements, such as replacement of conventional toilets with ultra low-flow models.
Resources
Weymouth Water Bank Implementation Plan, 1998. (On file at IRWA)
Water Wise Communities: Index
- Introduction & Using the Handbook
- How Development Affects Water (link to IRWA site)
- Checklist: Is Your Community Water Wise?
- Water Wise Tools:
