Expect Atypical Nantahala Flows This Spring and Possibly Longer (NC)

Posted: 03/14/2022

By: Kevin Colburn

Duke Energy has announced that they can only generate power and release water from the powerhouse at 50% of their normal capacity on the Nantahala River due to the failure of a transformer. The powerhouse is now capable of releasing 315 cfs versus the typical 630 cfs, and these conditions are likely to persist through May, and possibly considerably longer. Duke Energy will be releasing flows from the dam into the Upper Nantahala, which is normally bypassed by a tunnel between the dam and the powerhouse, in order to maintain reservoir levels and meet downstream recreational release requirements.

Spring on the Upper Nantahala

On the Cascades and Upper Nantahala the public can expect continuous releases all spring, with the typical release being approximately 315 cfs. If we enter a very dry period the releases could drop, but it is more likely that releases will be occasionally increased to maintain reservoir levels following rain events. Note that there are some tributaries that will add additional flows. In other words, paddlers can expect boatable flows 24-7 this spring in the Upper Nantahala except for periods of very high water.

Spring on the Lower Nantahala

On the Lower Nantahala the public can expect the normal recreational releases to be provided on the normal schedule and at typical flows this spring. Duke will provide these releases by releasing 315 cfs at the dam and 315 cfs at the powerhouse. During times when recreational releases are not scheduled the Lower Nantahala will have the same continuous flows as the Upper Nantahala: 315 cfs plus tributary inflows, subject to change as needed to manage reservoir levels, plus frequently an additional 315 cfs from generation. 

Summer Is Unclear

There is a possibility that the hydropower project can be repaired by June, but there is also a possibility that repairs could take a year or longer to complete. We’ll know more soon and will be in regular communication with Duke Energy. If repairs are not completed until after May, water temperatures will rise to a point that federal regulators will likely limit Duke’s ability to release relatively warm water from the dam, and some portion of the summer Lower Nantahala recreational releases may be canceled or otherwise modified. Duke Energy will be hosting weekly updates and American Whitewater will participate, advocate for releases, and keep paddlers posted.