50 Million Mussel Project, Potomac Riverkeeper Network

Putting some Mussel back in the River!

Overview of the Project

The Potomac Riverkeeper Network has launched an ambitious project to restore 50 million native freshwater mussels to the Potomac River by 2030. Like oysters in Chesapeake Bay, freshwater mussels filter nutrients, toxins and sediments from river systems. The time to act is now – studies show the Potomac River has reached the point where it can once again support vibrant mussel populations. Building a thriving population of these small but mighty creatures is the critical next step towards improving (and maintaining) water quality in the Potomac.

Our work is already underway. Join us and do your part to support this incredibly important program.

The Power of Mussels

Mussels can filter up to 10 liters of river water per day, providing incredible cleaning power. Freshwater mussels like Eastern Lampmussels, and Alewife Floaters are among 16 species native to the Potomac River and its tributaries, and once existed in the millions, similar to the oyster populations in the Chesapeake Bay. Scientific opinion is unanimous that the reintroduction of mussels is an important part of restoring our river ecology and improving the water quality in the Chesapeake Bay; Washington, DC, Maryland and Virginia’s Departments of Environment are committed to the recovery of native mussel species in local waters.

The Tipping Point

Mussel studies conducted by Anacostia Watershed Society (AWS) around Kingman Lake on the Anacostia River indicate that water quality on the Potomac and its tributaries has improved enough that the ecosystem can sustain naturalized mussel populations.

Getting Started

In 2019, Potomac Riverkeeper Network (PRKN) partnered with National Harbor, Oasis Marinas and Maryland Department of Environment (DNR) to launch the 50 Million Mussel Project with the installation of a freshwater mussel nursery adjacent to our floating lab housed on MV Sea Dog at National Harbor, Oxon Hill, MD. Early analyses indicate that this location has reached a suitable environmental state for sustaining a vibrant wild mussel population as well as a future floating wetland ecosystem

Challenges Remain

The primary threat to mussel survival is sedimentation caused from stormwater runoff, which can smother the mussel beds and cause turbid conditions that prevent sunlight penetration needed for underwater grasses that provide protection and food supply for the host fish that are a critical part of the mussel life cycle.

Suspending oysters in baskets above the river bottom has proved to increase their survival, as the baskets can be pulled up, brushed off, and re-submerged into the water column, preventing sediment buildup from suffocating the mussels. At first, mussel nurseries will be built using this technique. As conditions improve, we expect mussels will begin to self-propagate on the river bottom.

Next Steps

With the help of donations, grants and corporate sponsors, we will continue to grow the funding support for this vital project. Potomac Riverkeeper staff, partner organizations and many passionate volunteers will help build, install and maintain more and more “floating wetlands” at locations we have identified along the Potomac River. As the river clears, mussels will be introduced to the river bottom and will become self-sustaining. We hope this project will become a model for future efforts to re-introduce native freshwater mussels in many of the rivers that flow into the Chesapeake Bay.