Volume 29 Issue 4, Fall 2024

by Kim Strader

Three Double-crested Cormorants perch in a dead tree in the wetlands. Photo by Michael Sciortino.

The Dulles Greenway Wetlands, home to the Dulles Greenway Eagles, celebrates its 30th anniversary in 2025. The creation of this preserve, also known as the Dulles Greenway Wetlands Mitigation Project, was mandated to compensate for wetlands permanently impacted by the construction of the toll road. This 149-acre site in Loudoun County is “protected by permanent conservation easements, to be maintained in perpetuity as undisturbed natural areas,” according to the 1995 plan for the wetlands’ establishment.¹

With no places to park or paths to walk, minimal maintenance, and entrances masked by vegetation, this privately owned preserve remains an undisturbed natural area for wildlife three decades after it was created.

Importance of Wetlands and Mitigation Projects

Mitigation projects such as the Dulles Wetlands provide a tool to compensate for unavoidable wetland loss due to development. As Loudoun County continues to be under pressure to develop more homes, businesses, data centers, and roads, wetlands remain at great risk. Wetlands are vital habitats because they:

• Control erosion by slowing the rate at which water enters streams and rivers.
• Provide flood protection by helping contain water that might otherwise overflow stream and riverbanks.
• Improve water quality by absorbing pollutants before they enter streams and rivers.
• Provide areas rich in plant and animal biodiversity. One-third of all threatened and endangered species in the U.S. live in wetlands, and some species can be found only in these habitats. Many species of wildlife call the Dulles Wetlands home and are fortunate to have this space that is unencumbered by human interaction.

A camouflaged Gray Tree Frog hides in plain sight on a fallen log. Photo by Jenny Erickson.

Dulles Wetlands Mitigation Project

The Dulles Greenway Wetlands compensation program called for the mitigation of lost habitat to be in excess of and “to provide ‘in-kind’ habitat replacement for wetland types filled”¹ by the toll road’s construction at a ratio of 2:1. The goals and measurements of success of the Dulles Greenway Mitigation Project were, according to the 1995 plan, to:

• Restore wetland hydrology to former floodplain wetlands currently drained by farming practices.
• Revegetate the restored areas with a diverse assemblage of wetland forest and shrub species.
• Increase wildlife habitat along the floodplain of Goose Creek by creating large, continuous areas of mixed wetland and upland forest.
• Permanently preserve open space and protect wetlands through conservation easements

The project was completed in two phases, with the North site beginning in 1993 and the South site in 1995. Prior to the project, a portion of the land was used for corn and/or hay production through 1992 and had been significantly altered by diverting a stream and digging drainage ditches.

A pretty morph garter snake is safe at home in the wild of the wetlands. Photo by Jenny Erickson.

To accomplish these goals, surface grading was performed, weirs and sediment traps were installed, erosion was controlled, and wetland and upland trees and shrubs were planted. Following completion of the project, monitoring was conducted for a number of years to determine if the goals were met. Two of the goal assessments were to identify dominant plant species and wildlife species observed.

Monitoring for Success

Subsequent goal assessment reports indicated “a strong dominance of wetland plant communities throughout the sites,” and observed wildlife included: “deer, red fox, mallard ducks, black ducks, Canada geese, green heron and red tailed hawk,” Kurt Philipp of Wetlands Research Services reported in a July 6, 2004, letter to the Dulles Greenway.² His May 18, 2005, report states that “beaver signs are everywhere,” and “Most notable is an apparent Bald Eagle nest … I spoke with local birder, Joe Coleman [Loudoun Wildlife Conservancy founding member and current Board member], who was aware of the nest. He and fellow birders noticed the nest being built in December and suspect that the nest may be active with young.”³

The beavers remain active at the wetlands and play a vital role in continuing to help build this important and vibrant wildlife habitat. The Bald Eagles, as we know, continue to inhabit the site and, thanks to the Dulles Greenway installing nest cameras in 2021, we are able to view their daily lives online today, with Loudoun Wildlife volunteers providing interpretation of what we see.

A resident Pickerel Frog briefly tolerates admiration from a wetlands visitor. Photo by Jenny Erickson.

Loudoun Wildlife Conservancy partners with the Dulles Greenway to provide occasional on-site educational opportunities and to conduct wildlife monitoring at the wetlands. Joe Coleman began recording bird species there during the 1997 Christmas Bird Count, and to date, 206 bird species have been recorded at the Dulles Wetlands.⁴ Guided walks are offered each spring and fall to observe birds. Jenny Erickson, our Amphibian Monitoring Program coordinator, offers some walks as well and has done preliminary scouting for amphibians and reptiles. She also installed several wildlife cameras that have given us close-up views of other wildlife, including River Otter latrine behaviors

Loudoun Wildlife is proud to partner with the Dulles Greenway on the Eagle Cam Program and in monitoring and stewarding the wetlands property. It has been interesting to see how the mitigation project and nature have transformed cornfields into wetlands over the last 30 years. While we at Loudoun Wildlife prefer to protect and conserve natural areas, we realize that is not always possible given the continued pressure for development. The Dulles Greenway Wetlands Mitigation Project shows there are tools available to compensate for the loss of wetland habitats — tools to create places where land is protected and maintained as undisturbed natural areas.

Kim Strader, Loudoun Wildlife’s volunteer coordinator, is the former assistant curator of the Native Plant Trail at the State Arboretum of Virginia at Blandy Experimental Farm.

Bald Eagle parents Rosa and Martin watch over eggs DG3, DG4, and DG5 (named Pi, Pat, and Flora as eaglets) in February 2023. Photo by Cindy Bertholdt.

Quote References and Resources:
¹Wetland Research Associates, Inc. (1995). Dulles Toll Road Extension Compensatory Wetland Mitigation, Wetland Compensation Plan – B-5 South (COE Permit: 90-1855-15).
²Philipp, Kurt, PhD, Wetlands Research Services. Letter to Dulles Greenway. 6 July 2004.
³Philipp, Kurt, PhD, Wetlands Research Services. Letter to Dulles Greenway. 18 May 2005.
⁴eBird.org. Dulles Greenway Wetlands Mitigation Project. Retrieved September 25, 2024, from https://ebird.org/hotspot/L392038/bird-list?rank=hc

The post Wild About the Wetlands: Celebrating 30 Years of the Dulles Greenway Wetlands appeared first on Loudoun Wildlife Conservancy.