Fish Habitat Partnerships Making a Difference Low Dam Removal on the Harpeth River, Tennessee
from the National Fish Habitat Partnership's 2015 Through a Fish's Eye Report
Summary
Partnership - Southeast Aquatic Resources Partnership The Harpeth River drains nearly 900 square miles in middle Tennessee and flows through one of the fastest growing regions in the country. It is a state designated Scenic River in Davidson County, within 30 minutes of downtown Nashville. The river is one of the most archeologically and historically significant rivers in the state. However, the project area was listed on the U.S. EPA Section 303(d) list for siltation and habitat alteration, nutrient enrichment and low dissolved oxygen. Low dissolved oxygen was particularly an issue above a 6.2 foot low head dam near Franklin, Tennessee. Dissolved oxygen measurements at this dam were below state standards, and fish are unable to [...]
The Harpeth River drains nearly 900 square miles in middle Tennessee and flows through one of the fastest growing regions in the country. It is a state designated Scenic River in Davidson County, within 30 minutes of downtown Nashville. The river is one of the most archeologically and historically significant rivers in the state. However, the project area was listed on the U.S. EPA Section
303(d) list for siltation and habitat alteration, nutrient enrichment and low dissolved oxygen. Low dissolved oxygen was particularly an issue above a 6.2 foot
low head dam near Franklin, Tennessee. Dissolved oxygen measurements at this dam were below state standards, and fish are unable to migrate freely past this barrier. In the headwaters, agricultural activity and failing septic systems are the primary causes for low dissolved oxygen, siltation and habitat loss.
The Harpeth River is incredibly biodiverse. Below the low head dam site, 54 species of fish have been recorded, as well as two federally listed endangered species of mussel (the
Tan Riffleshell - Epioblasma florentina walkeri and the
Pink Mucket Pearlymussel - Lampsilis abrupta). Restoring the river to a free-flowing state was crucial to the survival of these species as nearly all of them need good water quality and the ability to migrate freely. The Harpeth River Watershed Association (HRWA) secured $350,000 from collaborative funding programs of the U.S. Fish and Wildlife Service, Southeast Aquatic Resources Partnership, and the National Fish Habitat Partnership and $70,000 from the city of Franklin that together were used to improve fish habitat and water quality and remove the fish passage barrier. The project was completed in April 2013, removing the only fish movement barrier on the Harpeth River. The dam was replaced with a double cross-vane low boulder structure, which rehabilitated two miles of river habitat, reconnected 36 miles of river, and restored riffle/run aquatic habitat that was formerly submerged. Eroding banks were stabilized and vegetation was planted in the previously impounded area, reducing the sediment load from this unnatural erosion. Restoration efforts improved dissolved oxygen levels and benefited species of concern found in the sub-watershed. Additionally, a canoe access was installed that has allowed additional public access to this unique gem.
This project was given the 2013 Governor's Environmental Stewardship Award as well as the National Fish Habitat Partnership "10 Waters to Watch” Award for the year 2012. The removal of this dam has made the Harpeth River one of the only rivers in Tennessee that is entirely free flowing through its
entire length.
The U.S Geological Survey (USGS) is partnering with the National Fish Habitat Partnership (NFHP) to produce the 2015 report entitled, "Through a Fish's Eye: The Status of Fish Habitats in the United States 2015". The information contained within this item is a product of NFHP. The Bureau is neither responsible nor liable for the accuracy or the use of the scientific content within this item. This content is considered preliminary pending subsequent review and approval.
