Why does the river experience low flows?
Flows in the Ipswich River in summer and fall are typically only a small fraction of what they would be under natural conditions. A USGS hydrological model determined that flows in the upper river were less than 10 percent of what they would naturally be. Sometimes low flow conditions continue throughout the winter and even into spring. The main factors which cause unnaturally low-flows are water withdrawals, transfers of water out of the watershed, and the effects of development in preventing the recharge or replenishment of groundwater. Pumping of water supply wells located near the river or tributary streams is particularly damaging. This pumping depletes groundwater that would otherwise keep the river flowing, and also induces flow from the river into the well, as shown in illustrations below. These wells pump the most in summer, when there is least water available, to meet high demand for lawn watering and other non-essential uses of water. The Ipswich River experiences low-flows
