Balancing the Water Budget in the Ipswich River Watershed

In Massachusetts, adjacent towns often draw from a shared water supply without a shared vision of, or responsibility for, its protection and management. Thus a river can be healthy and flowing in one town, but polluted and dry in another, leaving the municipalities most affected to bear the impact of unwise choices made by other communities. The Ipswich River is a case in point. In 1997, after recurring instances of no-flow, the national environmental group American Rivers designated the Ipswich River as one of the 20 most threatened rivers in the country. The group named water withdrawals, development, and pollution as the central factors responsible for the river's degradation. Human land uses and water withdrawals in the watershed have altered the river to the point that it is drying up on a regular basis.Many rivers, including the Ipswich, are fed through the groundwater supply, which serves as a natural underground reservoir, or aquifer, continuously replenishing the river. Although precipitation and groundwater in Massachusetts are relatively abundant, some human land uses and water consumption patterns threaten the quantity and quality of water resources. The increased development of buildings, roads, and other impervious surfaces brings associated increases in water use and surface water runoff. Water draining from a developed watershed exits from the watershed more rapidly, diminishing the amount of water recharging or renewing groundwater aquifers, in turn diminishing the amount of water to feed the streams and rivers that rely on this groundwater.Compounding this situation, both wells and reservoirs provide water for human consumption withdrawing groundwater and surface water which would otherwise replenish the river. The impacts to the river are exacerbated during droughts or dry summers because water demand increases coincident with the time the natural system has the least water to “spare.”Water may also be lost from the watershed through centralized sewering if the water is diverted to another watershed, again diminishing water to the aquifer and further depleting groundwater levels. Sewers not only remove human wastewater from the watershed, but may also remove clean water through significant amounts of “infiltration and inflow.”The net result of these human alterations to the hydrologic budget, is the removal of more water from the watershed than is returned, leaving the river system dramatically altered and unable to sustain its other essential functions and values. This is the central problem in the Ipswich River watershed.To deal with these issues a watershed management council and a watershed management plan are being developed to restore flow to the Ipswich River. Because of the complexity of the issues and numerous stakeholders involved, there will be multiple solutions and recommendations made to alleviate impacts on water quantity to the river. One innovative method proposed is a “water balance” policy that each town would adopt. The framework of the policy is a no net loss policy for water resources within the watershed. This will require each town to develop a hydrological budget i.e. determining the amount of water they contribute or withdraw in the watershed. Multiple tools can be used to reach this policy goal. Under consideration are water conservation measures, increasing stormwater recharge from new development within the basin at a 2:1 or 3:1 ratio, protection of recharge zones, encouraging either decentralized wastewater or sewered waste to stay within the basin or importing sewer from outside the basin.