Aquatic Ecosystem Restoration in Maryland
An ICC team member gently measures a rescued box turtle that was moved to a safe location prior to construction.
The Maryland State Highway Administration (SHA) took on the largest project in its history with the development of the Intercounty Connector (ICC), an 18-mile roadway connecting I-270, US-29, I-95 and US-1. To mitigate the ICC's environmental impacts, SHA mounted an extensive Environmental Stewardship (ES) effort in the Rock Creek, Northwest Branch, Paint Branch and Indian Creek watersheds that are crossed by the ICC. The Paint Branch aquatic system encompasses several small spring-fed streams that converge into a larger stream. Since 2003, SHA has been studying the stream water quality, designing and constructing ES interventions that will improve conditions in the Paint Branch watershed by preventing uncontrolled stormwater runoff, reconnecting floodplains, restoring natural contours to streams, and enhancing water-dependent habitats.
Crews prepare for the next step in the construction of Culvert Z, a bottomless BeBo, which Mill Creek will run through and will provide safe passage for wildlife.
The ICC runs through two Maryland counties—Montgomery County and Prince George's County—that have experienced intensive urban development since the 1960s. Stormwater management regulations were inadequate for much of this time period. Uncontrolled stormwater runoff from many communities degraded local water quality. The runoff also eroded stream channels, making the streams shallower and raising water temperatures, which is detrimental to species health.
As runoff problems intensified, the negative impacts spread beyond developed areas into protected areas such as the Upper Paint Branch Special Protection Area. The Special Protection Area consists of stream valley parklands located at the upper reaches of the Paint Branch watershed. This watershed provides a habitat for one of the last naturally reproducing populations of brown trout in Montgomery County. The Upper Paint Branch area is especially important for the trout's' survival because it supplies them with necessary coldwater baseflow and spawning/nursery areas.
These wetlands have been restored and are located just north of Bonifant Road in Contract B. PB 123.
SHA invited county, state, and Federal agencies to participate in an Interagency Work Group (IAWG) to design an ES initiative for improvement of the Upper Paint Branch watershed. Agencies represented in the IAWG included the U.S. Environmental Protection Agency, the U.S. Army Corps of Engineers, the U.S. Fish and Wildlife Services, the National Park Service, the Federal Highway Administration, the Maryland Department of the Environment, the Maryland Department of Natural Resources, the Maryland Transportation Authority, the Maryland-National Capital Park and Planning Commission, Montgomery County, and Prince George's County.
The IAWG agencies provided data from Paint Branch watershed studies and reviewed SHA's assessment of existing conditions. The assessment results indicated that retrofitting the antiquated existing systems or constructing missing stormwater management systems in surrounding communities would make the greatest contribution toward improving the Upper Paint Branch ecosystem. ES interventions focus on three major concerns: dissipating stormwater to prevent erosion, promoting stormwater infiltration into the soil, and shading areas vulnerable to high water temperatures.
This active contract in the Paint Branch watershed is enhancing existing storm water management features within local neighborhoods.
Stormwater interventions will take place on both private and public lands. SHA has taken responsibility for gaining the buy-in of private homeowners and developing a number of mitigation strategies that would not adversely affect homeowners' personal properties. These strategies included removing concrete-lined ditches, increasing tree and ground cover around drainage areas, and creating bioswales to promote stormwater infiltration. SHA used the same strategies within the Montgomery County right of way to mitigate the effects of impervious road surfaces. Through the IAWG partnership, Montgomery County volunteered to take over the long-term maintenance of all projects on county-owned land.
Implementation of the ES interventions began in 2003 and will continue through 2017. In order to monitor the effectiveness of the interventions, the ES plan includes biological monitoring and water quality testing to measure Upper Paint Branch water conditions before and after implementation.
The Upper Paint Branch ES project goes beyond the usual scope of a highway mitigation project by addressing stormwater runoff problems at an ecosystem scale. These runoff interventions will help preserve the Paint Branch population of brown trout and maintain one of Maryland's only urban coldwater fisheries.
For more information, contact Rob Shreeve, firstname.lastname@example.org.