The Walloomsac River (pronunciation: WAWL-oom-sik) is a tributary of the Hoosic River, 30 miles (48 km) in length, in the northeastern United States. It rises in southeastern Vermont, in the Green Mountains east of the town Pownal and flows north and west past Bennington to join the Hoosic below Hoosick Falls, New York.
The northern portion of the town is drained by the Walloomsacriver, which flows from the east line in a generally westerly course to the Hoosick.
Near the junction of the Walloomsac and Hoosick rivers in the north part of the present town was a hamlet called St. Croix in colonial times, probably so named by French missionaries who evidently explored the country as far south as the Hoosick river and there established a mission.
Walloomsac is a small hamlet on the Troy and Bennington railroad in the northeastern part of the town.
East of the river, the rocks consist of a slaty shale and limestone, the latter furnishing lime.
This patent contained 12,000 acres, on both sides of WalloomsacRiver, and lying partly in Washington co. and Vt.; it was granted to Edward Collins, James De Lancy, Gerardus Stuyvesant, Stephen Van Rensselaer, Charles Williams, and Frederick Morris.
The surface consists of the narrow valley of Hoosick River and the wild rocky regions of the Taghkanick and Petersburgh Mountains, rising respectively on the east and west.