Total streamflow across the Mill River was last observed at 389 cfs, and is expected to yield approximately 772 acre-ft of water today; about 158% of normal. River levels are high. Average streamflow for this time of year is 246 cfs, with recent peaks last observed on 2019-03-01 when daily discharge volume was observed at 7,280 cfs.

Maximum discharge along the river is currently at the Mill River At Northampton reporting a streamflow rate of 389 cfs. This is also the highest stage along the Mill River, with a gauge stage of 7.65 ft at this location. This river is monitored from 3 different streamgauging stations along the Mill River, the highest being situated at an altitude of 205 ft, the Mill River At Northampton.

The Mill River is a 15-mile-long river in western Massachusetts, originating in the town of Williamsburg and flowing into the Connecticut River in Northampton. It has a rich history dating back to the early 18th century, when it was used to power mills and factories along its banks. The river's hydrology has been heavily impacted by human activities, including the construction of multiple dams and reservoirs for industrial and municipal use. Notable reservoirs include the Leeds Reservoir, the Williamsburg Reservoir, and the Hatfield Reservoir. The river also provides recreational opportunities, including fishing, kayaking, and hiking, and supports local agriculture through irrigation. Despite ongoing challenges related to water management and pollution, the Mill River remains an important natural resource for the region.