Maximum discharge along the river is currently at the reporting a streamflow rate of cfs. This is also the highest stage along the Walloomsac River, with a gauge stage of ft at this location. This river is monitored from 1 different streamgauging stations along the Walloomsac River, the highest being situated at an altitude of ft, the .

The Walloomsac River is a 16.7-mile-long tributary of the Hoosic River, located in southwestern Vermont and northwestern Massachusetts. The river has a rich history, with the first known European settlement established along its banks in the 1760s. Today, it serves as a source of drinking water for several communities, and a number of small hydroelectric dams operate along its length. The most notable of these is the Harriman Reservoir, which is the largest body of water in southern Vermont and serves as a popular destination for boating and fishing. The river also supports local farms and orchards, and provides opportunities for recreational activities such as hiking, camping, and wildlife watching. However, the river's health is threatened by a range of issues, including pollution from agricultural runoff and industrial activity, as well as damming and development along its banks.