The Sacandaga River's headwaters north of Great Sacandaga Lake begin in the town of Lake Pleasant. From Lake Pleasant, the river follows a short moving course or path known as the Sacandaga Outlet into Lake Pleasant. The Sacandaga River drains Lake Pleasant at a location next to the public beach in the village of Speculator. The river then follows a winding path through some wetlands and various ecosystems through the county. In Speculator, the Sacandaga River Community Park was built by local volunteers and has a number of boardwalks and pathways that follow the course of the river. Near the town boundary between Wells and Lake Pleasant, the river flows into a series of ponds. The Sacandaga River course takes a steep path flowing over a series of waterfalls including Christine Falls and Auger Falls. The East Branch joins the trunk stream in the town of Wells. After flowing through Wells, the river enters Lake Algonquin, a manmade impoundment constructed in the 1920s to stimulate the community's tourism industry. The East Branch goes through Johnsburg in Warren County and flows parallel to, in part, NY Route 8, passing the communities of Oregon in Johnsburg and Griffin in the town of Wells. The Sacandaga flows out of Lake Algonquin into a hydro-electric plant and follows a course of rapids to Great Sacandaga Lake through the towns of Hope and Benson. In that area, it connects with Groff Creek. Then it enters the Great Sacandaga Lake in the village of Northville, which it flows through the lake to the Conklingville Dam. Which then it enters the town of Hadley, where it ends at the Hudson River.
Hydrology
The United States Geological Survey maintains a few stream gauges along Sacandaga River. The one station located upstream from Hope, had a maximum discharge of per second on March 27, 1913, and a minimum discharge of per second on September 30, 1913. Another station located upstream from the mouth in operation since 1907, had a maximum discharge of per second on March 28, 1913, and a minimum discharge of per second on May 4, 1985, March 30–31, and many days in April 1992. Since the construction of Great Sacandaga Lake in 1930, the maximum discharge was on May 2, 2011.
Tributaries
Right Johnson Vly Stream Shanty Brook Dunning Creek West Branch Sacandaga River Groff Creek Petes Creek West Stony Creek Cloutler Creek Batcheller Creek Gordons Creek Daly Creek Breen Brook Left Kunjamuk River Fly Creek Robbs Creek Macomber Creek East Branch Sacandaga River Mill Creek Coulombe Creek Doig Creek East Stony Creek Beecher Creek Sand Creek Glasshouse Creek Paul Creek Allentown Creek Bell Brook Mink Brook Man Shanty Brook
Dam and reservoir
The Conklingville Dam, finished in 1930, located by the west town line of Hadley, greatly expanded the width of the river, creating Great Sacandaga Lake, formerly called the Great Sacandaga Reservoir.
