Pennsylvania Department of Transportation

Pennsylvania's Ecological Mitigation and Enhancement Projects

A segment of Marshall Creek has been preserved to protect the Bridle Shiner and Iron-colored Shiner. (PennDOT)

A bog turtle being fitted with a radio transmitter. (Teresa Amitrone)

Stream located in U.S. 220 mitigation area. (PennDOT)

The Bigger Picture. To minimize road construction impacts on ecosystems, the Pennsylvania Department of Transportation (PennDOT) and its environmental partners are using holistic landscape approaches and common-sense watershed-based mitigation strategies. They're focusing on linking important habitats, maintaining and enhancing biodiversity, and combining wetland mitigation with terrestrial enhancement and stream preservation.

Here are three examples of their efforts:

Marshalls Creek Mitigation Strategy

Marshalls Creek in northeast Pennsylvania is home to the tiny Bridle Shiner and Ironcolored Shiner (the only known population in the State). So even though a proposed U.S. Route 209 bypass wasn't expected to have the slightest effect on the creek, PennDOT was taking no chances.

The PennDOT worked with the U.S. Army Corps of Engineers (COE), the U.S. Fish and Wildlife Service (FWS), the U.S. Environmental Protection Agency, the Pennsylvania Game Commission, the Pennsylvania Fish and Boat Commission (PFBC), and the Pennsylvania Department of Environmental Protection (DEP) to make sure development in the mostly commercially zoned areas next to the creek wouldn't threaten the shiners. The project team reached amicable agreements with landowners to sell PennDOT 123 acres of mixed uplands, wetlands, and riparian habitats.

Protecting and enhancing the acquired habitats has involved PennDOT in a whole host of activities, from preserving vernal pools to removing invasive species and planting warm-season grasses to restoring more than 5,000 feet of stream channel. Five "mammal passages" will be built, enabling foxes, black bears, and other area wildlife to safely cross under the highway to reach Marshalls Creek. One of these underpasses will feature a "skylight"—a separation of the north- and south-bound lanes to allow more light to enter the structure. A second box culvert structure will be depressed to ease the journey for snakes, salamanders, turtles, and other herpetiles.

As for the shiners...There will be more of them, because PennDOT has funded a Penn State University shiner study, including raising offspring from native shiner stock (this has never been done before in a laboratory). The native shiners and their offspring will be reintroduced to other areas of the watershed. So far, more than 10,000 shiners have been bred.

U.S. 222 Ecological Mitigation and Enhancement Features

A little turtle is getting a lot of attention in Pennsylvania. PennDOT is spending time, money, and energy making life easier for the federally endangered Bog Turtle—a small, dark-brown-to-black turtle with an orange spot on either side of its neck.

When some bog turtles were discovered on a U.S. 222 safety-improvement project outside Reading in Berks County, PennDOT consulted its Federal and State partners—the COE (the lead agency), FWS, DEP, and PFBC. Together, they came up with an extremely ambitious action plan that won full support from the permitting agencies.

According to the plan, PennDOT would improve existing bog turtle habitat and potential travel corridors...create new habitat and remove impediments to existing potential habitat and travel corridors...and establish temporary easements on private property adjacent to the construction site for further habitat enhancement.

To meet these goals, PennDOT completely redesigned two bog turtle passageways, extending one 20-foot structure to 60 feet and converting a 48-inch pipe to a 20-foot bridge.

PennDOT has also improved four wetland sites, changing the grading to create the hydrologic conditions necessary for bog turtle habitat, and revised the planting plan. The temporary easements have allowed PennDOT to remove unsuitable habitat outside the right-of-way, like wild rose and red maple which block sunshine or impede turtle movement.

Bi-weekly tracking of the turtles' movements with grape-sized radio transmitters placed on the animals' shells is yielding valuable information on how many turtles have entered the work zone (so far, none have). The frequent monitoring will also enable wildlife researchers to better understand what habitats the bog turtles prefer, when they migrate, how far they move, where they hibernate, and how individual turtles change over time.

U.S. 220 Natural Resource Compensation Plan

It's difficult and impractical to replace wetlands located on mountain slopes. So when safety improvements on U.S. 220 in Pennsylvania impacted 350 wetland sites, many of them on Bald Eagle Mountain in the Appalachians, PennDOT mitigated the impacts where the work would do the most good—in the valleys and on the farmlands below the highway project.

Since the 22,000-acre project disturbed terrestrial and stream habitat as well as wetlands, PennDOT and its Federal and State partners integrated all three components into a single Natural Resources Compensation Plan. The plan committed PennDOT to mitigate impacts by providing 160 acres of wetland creation, restoration, and enhancement; 597 acres of terrestrial habitat preservation; and 21,377 feet of stream habitat. The PennDOT also agreed to develop a habitat management plan for a perennial called the Matted Spikerush (a Federal species of concern), to fund conservation in important bird areas, and to survey for the presence of the federally-endangered Indiana Bat. What's more, PennDOT committed to preserving or enhancing 200 acres of forest, 31 acres of shrub land, 50 acres of wildlife corridors, 85 acres of wildlife remnant parcels, and 10 acres of wildlife buffer zones.

To see where all this mitigation and enhancement might occur, PennDOT evaluated each of 12 area watersheds. The U.S. 220 Mitigation Work Group then developed a priority listing of potential mitigation sites with the best chance for providing ecological and social benefits within a watershed context. The priority listing was used to make amicable agreements with owners of properties like the Liner Site in Centre County. Thanks to cooperation between PennDOT and the landowner, contractors were able to install streambank cattle fencing on the site.

The plan will greatly benefit the North and South Bald Eagle Creek nearby. And it may serve as a template for future PennDOT projects involving multiple mitigation components and goals within a large study area.

For more information contact Lonnie Young at lyoung@rettew.com (Marshalls Creek); E. Jerry Neal at eneal@state.pa.us (U.S. 222); or Kim Bartoo at kbartoo@state.pa.us (U.S. 220).