COLLEGE PARK – While Purple Line opponents fight over environmental harm they think the light rail line will cause, members of the construction team are planning environmental remediation measures to improve a stream near the line’s future path.
Members of the Purple Line team held a community meeting Monday, Jan. 9, to discuss the Paint Branch stream restoration planned as an environmental mitigation project for the line and get community feedback on the plans. An approximately 2,900 linear foot section of Paint Branch – bounded by the east where the stream meets Indian Creek and on the west by the CSX railroad, all in the Berwyn Heights/College Park area – is slated for improvements designed to reduce erosion and create better habitat for fish and other species that call the river home.
Mike Madden, who works at the Maryland Transit Administration (MTA) as deputy director of the Purple Line project, said while wetlands work will be undertaken elsewhere, this project is the sole stream project currently planned by the Purple Line team.
“Purple Line has some impacts, roughly 5,000 linear feet of impacts, to streams. And as a result of that, we need to compensate or mitigate for that impact,” Madden said. “Our plan has been for quite a few years to do work on Paint Branch, work in terms of restoring the stream bed and things like that.”
The specific site for mitigation was chosen because of its proximity to the Purple Line’s path and because the land is owned by the Maryland-National Capital Parks and Planning Commission (M-NCPPC), which makes getting the necessary permissions easier. The project members said improving this section of stream will have as much as a four-to-one positive impact because of connectivity with other restoration work done upstream.
Kate Scott, senior water resources engineer, said the restoration work will include log vanes and logjams consisting of logs anchored to the riverbank to create fish habitat; placing stones along the banks in specific locations to stop erosion; adding riffle pools to help fish swim upstream; and creating “back eddy roughness.”
“The roughing or features of back eddy roughing, one of the furthest ones that is proposed here is actually going to be constructed into the bank, and the other one is going to have a sill on the side,” she said. “The purpose of this is to have all the water go into the center of the stream instead of along the banks to slow down erosion.”
A variety of native vegetation will also be planted in the area. Materials already found in or around the stream, such as rocks, will be used when possible. The team also plans to harvest select trees from the site to use in the logjams.
MTA is handling the contracts for the work. It will take approximately 18 months to complete, but according to Patrick Dinicola, a project manager, some of the length of that timeframe is because the team is not able to perform work during certain times of the year.
Dinicola also said the work would have some impacts on the walking and biking trails in the area around the project sites, which are part of the trail system of the Paint Branch Stream Valley Park and around Lake Artemesia. A section of the trail would be closed to the public while work takes place, and trucks and other equipment would need to cross the trail at two specific locations, one north of the trail as it runs parallel to the stream.
“There will be a crossing to get into the woods across that trail,” Dinicola said. “They’ll have flaggers there. So there may be occasional stops to pedestrians and cyclists when they move back and forth. But that shouldn’t be like, we’re closing it down for half a day. It will be just a five minute stop.”
Community members in attendance voiced concerns about impacts to the trail infrastructure itself, because the trails are heavily used by residents in the area. Dinicola said the contractors would be required to check it daily for rocks and other debris, and to repair any damage that is caused to the asphalt.
Construction-related traffic would also operate on roadways at the College Park Airport, where the county police department houses their helicopter. Staff said impacts would also be minimal, and personnel will be on site monitoring the situation.
“We will react to the airport as opposed to them being impacted by us,” Dinicola said.
Residents also expressed concerns about maintenance of the structures put in place during the restoration. Although M-NCPPC owns the land, they will not be responsible for maintaining the structures.
Scott said the materials are durable and will be monitored for damage.
“As long as the woody debris is saturated, it will last pretty long, is my understanding,” Scott said. “Once you’re stabilizing that bank and you’re planting on top of it, it kind of just becomes naturalized and self-maintaining in that way.”
The team said they hope work can begin in March 2018, but that is dependent on when the lawsuit currently halting Purple Line construction is resolved. The Purple Line team is waiting on a federal judge to respond to MTA and the Federal Transit Administration (FTA)’s assertion that an additional environmental impact study is not necessary based only on D.C. Metro ridership declines.