The Allegheny Reservoir
The Allegany Reservoir is the water reserves from the Kinzua Dam blocking Ohi:yo. It is one of the largest reservoirs in the U.S. and is made up of a third of our land that was once part of our Allegany Territory.
The reservoir on our Territory is seasonal: Ohi:yo' floods its banks every Spring to Fall. During Summer, water covers our land that we have used for generations. In Fall, much of the bottom of the reservoir has begun to dry up as the water reserves are lowered at the discretion of the U.S. Army Corps of Engineers.
As the reservoir is gradually brought down to winter pool elevation it leaves behind vast tracts of land. The mudflats that are left behind are a reminder of the land that was lost and show the continued impacts, such as erosion and sedimentation.
At times of water storage the water depth of the river channel is approximately 26 feet, with as little as 6 to 8 feet of water during the winter months.
The seasonal lowering and emptying of the water reserves within the reservoir leave our inundated land exposed and unprotected to weather elements for part of the year. This annual exposure makes it difficult for natural vegetation to grow, which acts as a barrier to erosion caused in part by the frequent water-level fluctuations. Our native plants that grow along Ohi:yo' are also culturally important. Some plant species, such as sassafras, are used by our Seneca people for medicinal purposes.
Significant loss of our river's banks has been observed since the creation of the reservoir, which is likely a result of the frequent water level fluctuations, stream direction and velocities, wave action, and geological conditions.
In addition, the emptying of the reservoir in Fall leaves areas of landlocked water that fish get trapped in, leading to mass fish kills.
The Seneca people living on the Seneca Nation's Allegany Territory were not the only Seneca people directly affected by building Kinzua. The Cornplanter Grant located in Pennsylvania was also inundated, leaving Chief Cornplanter's heirs without their communities, their homes, and their land.