Rapidan Partnership begins study that could improve 541 miles of river

For more than 80 years, the dam spanning the river at the Rapidan Mill has blocked the migration upstream of any number of freshwater and anadromous fish seeking to spawn upstream.

Rapidan Partnership begins study that could improve 541 miles of river

By Jeff Poole

There’s an old joke that asks, “What does a fish say when it swims into a wall?”

“Dam.”

For more than 80 years, the dam spanning the river at the Rapidan Mill has blocked the migration upstream of any number of freshwater and anadromous fish seeking to spawn upstream.

That’s why a group of local, state and federal partners are working together to consider possible alterations to the 200-foot concrete dam in the village of Rapidan.

Last month, the Rapidan Partnership, a part of the Center for Natural Capital headquartered in the historic Rapidan Mill, announced the Rapidan Fish Passage Project—a study that could yield dam modifications with the potential to restore more than 540 miles of river habitat in Virginia.

Created in the spring, the Rapidan Partnership is comprised of representatives from the U.S. Fish and Wildlife Service, American Rivers, the National Oceanic and Atmospheric Administration, the Virginia Department of Wildlife Resources, Friends of the Rappahannock and the Piedmont Environmental Council.

According to project lead Jeff Waldon, the Rapidan dam represents the largest stream-passage issue in the Chesapeake Bay watershed. Or, as Center for Natural Capital Executive Director Michael Collins put it, “The only obstacle between the ocean and Hoover Camp (the headwaters of the Rapidan River) is the Rapidan dam.”

Buoyed by recent projects that successfully restored American shad populations in the Potomac and James rivers, and coupled with the knowledge that a number of those fish (and others) had been caught recently at the base of the dam, the partnership began taking a harder look at the 1936 concrete structure.

“If we’re going to be an environmental conservation group headquartered at the Rapidan Mill with a dam in our front yard, it behooves us to address that big issue,” Waldon said.

For centuries, American shad were plentiful in Virginia rivers and streams. Before pollution, dams and other human interference, they were among the most valuable and important fish in the Chesapeake Bay. History even records General George Washington feeding his troops on the spring shad runs in the Schuylkill River at Valley Forge in 1778.

But the dam—which is 11 feet high and approximately 12 feet deep—blocks the migration of American shad, hickory shad, striped bass, blueback herring, alewife, American eel and sea lamprey.

Notably, American shad are an anadromous fish, meaning they spend most of their lives in saltwater, but return to freshwater rivers to spawn and produce fish—like salmon.

Unlike salmon, they can’t propel themselves over large obstacles upstream—even with the aid of the “fish ladder” near the mill. (The gradient of the ladder is too steep for the migratory fish to navigate. The upstream Denil fish ladder at the Orange Water Treatment Plant intake is gradual enough to permit migratory species to clear the dam and swim upstream.)

“The fish ladder at Rapidan is not sufficient for shad, stripers or alewife,” Waldon confirmed. “These are sea creatures—not like salmon. They need a relatively low gradient—something more flat.”

In evaluating the impact of the dam on the watershed, the partnership learned creating a free-flowing Rapidan River could improve 541 miles of river habitat in the Chesapeake Bay Watershed both upstream and down.

The partnership is in the veryearly stages of what could be a three- or four-year project, Waldon explained.

“This is very preliminary, but it’s time to actively figure out what we should do. We need to do it carefully and intentionally and grind through the analysis and figure out the best plan of attack,” he said.

“We want to get the data and develop a plan that works for everybody.”

In addition to improving the quality of the watershed, a free flowing Rapidan could create a positive impact beyond the environment.

“There’s the aesthetic impact—the view of the river looking upstream would be spectacular—but there’s an economic impact and a recreational impact as well,” Waldon said. “The economic impact of a free flowing river is not inconsequential.”

After all, the dam—which is not a piece of public infrastructure—is a potential danger and a liability, requiring ongoing maintenance. While it has withstood historic floods and been subject to any number of trees, rocks and other debris hurtling downstream over the last 84 years, nothing suggests the hand-poured concrete and re-bar structure will continue to hold in perpetuity.

Even though the Department of Conservation and Recreation–which has regulatory authority over the dam—has ruled it a low-priority, low-risk dam, it represents the largest and most potentially beneficial project in the Chesapeake Bay Watershed, Waldon noted.

“The dam was put in for good reason—milling—but once that stops, there’s not much purpose in it,” he said. “There’s no economic reason to keep it. There’s no milling or hydrologic energy of any scale being created there or planned at the mill. Aesthetically, it’s part of the village, but the village was there before the dam and will be there long after it.”

Collins suggested modifying the dam to create a more free-flowing river could turn “a negative into a positive.”

“We can imagine fishing off the banks of the Rapidan with tens of thousands of 12 to 15-inch shad running during the spring,” Waldon said. “That’s what’s happening in Richmond and along the Potomac. That’s why the history part of this is so fascinating. The colonists relied on shad as a primary food source. The loss of that has been a big deal over time.”

Collins said one of the byproducts of the fish passage project could be the creation of a fishing club—like a hunting club—that would allow local members river access for recreational fishing.

Meanwhile, Waldon noted that larval and juvenile shad are a prime food source of rockfish—the most popular commercial and recreational finfish in the Chesapeake Bay—accounting for roughly $500 million in economic activity related to fishing, travel and lodging.

In 2019, Waldon said, the Atlantic States Marine Fisheries Commission found that the rockfish population was in trouble. Restoring upstream access could generate a significant downstream impact on rockfish and other species.

But both Waldon and Collins stressed the project is in its initial phase.

“We’re doing our due diligence, looking at all the issues, including the sediment behind the dam, the historic impact, the county impact and the economic impact,” Collins said.

After that, the partnership should know how or even if the dam could be altered. He said he hoped that study would be completed by mid-2021, and acknowledged it’s possible the study will determine no action should be taken.

Should the study yield a modification recommendation, the partnership would then proceed to the design and engineering phase and consider how best to fund any alterations.

“If we get through all that and feel we have a workable solution, then it’s a matter of raising money for the work,” Collins said, suggesting any funding might be a mix of grants, public and private funds.

“It’s a fascinating project,” Waldon said. “It’s large and complex and there are a lot of people involved. We’re working with experts and agency folks and everyone who might have a stake in the project. We’re looking at what’s feasible and what’s possible. Once we have the data, we’ll be reaching out to have community conversations.”

“We have the opportunity to create more than 540 miles of habitat,” Collins reiterated. “If we can achieve that, this likely will be a project of national significance.” 

Originally published at Daily progress