The Chandler Cove dam removal was one of three dam removals on Mill Creek that the Cumberland River Compact and its partners completed in 2018. Together, these projects won a Governor’s Environmental Stewardship Award in 2019. Thanks to the removals, all Davidson County sections of Mill Creek’s mainstem – about 21 miles – are now flowing freely to the Cumberland River for the first time in 50 years.
Mill Creek’s water quality was negatively impacted by excess sediment, nutrients, and pathogens, and also by low dissolved oxygen. The dam near Chandler Cove Way was contributing to almost all these issues, and after removal, many in-stream conditions improved quickly and dramatically.
Prior to removal work, Compact staff and volunteers walked or paddled 37 miles of streams in the Mill Creek Watershed, inventorying the 3 dams we removed on Mill Creek, plus 16 more dams on tributaries to Mill Creek. Most of the dams were small, no longer functioning as intended, and all but forgotten. Of the 19 we inventoried, only one was on the National Inventory of Dams, the most comprehensive database of dams at that time. The Compact and its partners also conducted crayfish sweeps, as Mill Creek is home to the endangered Nashville Crayfish. The team found and relocated 400+ crayfish and scheduled deconstruction work for June and August in order to avoid the reproductive season for this at-risk species.
No dams are designed to last forever, and at some point, the Chandler Cove dam failed.
At the time of its removal, a 15-foot breach was allowing Mill Creek to flow through the dam’s center. On either side of the breach, over 40 feet of concrete walls remained. All remnants of the dam were removed including three exposed girders, rebar spikes, and other surrounding debris, all of which represented a hazard to recreational paddlers. The areas disturbed by construction machinery in this process were stabilized with native seed, straw, and other plantings post-construction.
All areas disturbed by construction machinery were stabilized with native seed, straw and other plantings.
Removal of the dam enabled backwaters to flow freely again. Improved connectivity has allowed for easier species migration and increased genetic diversity within the creek (eliminating the “aquarium” effect produced between multiple dams on a single waterway). What was once a stagnant backwater with a sediment-filled bottom is now a mix of diversified habitat including riffles (fast and turbulent shallow water), runs (fast and smooth deep water), and pools. Flowing water prevents nutrients from pooling and causing harmful algal blooms, and it prevents sediment from building up and burying bottom-dwelling microorganisms beneath the muck behind the dam. Many aquatic species are sensitive to temperature increases, and the water that flows through MIll Creek today stays cooler than the slow-moving water that previously heated up behind the dam under the sun.
This work improved paddling conditions on Mill Creek and dovetailed nicely with the Tennessee Scenic River Association’s canoe access builds on Mill Creek’s mainstem. We’re proud to have lent a hand or two at several of these builds. In total, there are now six public access points in Davidson County on Mill Creek where paddlers can “put in” or “take out” their boats.
This work was completed in partnership with the Hidden Creek Homeowners Association, KCI Technologies, Metro Water Services Nashville, the Nashville Zoo, the TN Department of Environment and Conservation, and the TN Wildlife Resources Agency.