Traveling from my home in Denton through the Queen Anne area of Route 404, up to where it joins Route 50 near Wye Mills, my curiosity finally got the better of me. What were those rectangular holding ponds for? Why were so many trees taken down? What happens to the aquatic critters in the creeks that the road has to pass over? A call to the Maryland State Highway Administration (SHA) soon found me chatting with Bob Rager, the community liaison, who set to work connecting me with the folks on the project who deal with environmental concerns. I had the great privilege of meeting with a group of six transportation and environmental specialists in mid-July and visiting the worksite(s) of the Maryland 404 Widening project (yes, they even have a website! Check it out for the latest information about lane closures and traffic impact).
Stepping inside the cooled offices of the white farmhouse near Thawley Road where the project has set up headquarters, I was met by Fred Valente, SHA’s construction manager; the aforementioned SHA liaison, Bob Rager; Eric Freidly from the Environmental Programs Division of the SHA; Duncan Kerr, an independent environmental inspector; Gerry Hammel, the regional environmental coordinator; and even the summer intern, Diego Lezama, who was adding practical experience during a summer away from his engineering studies at Clarkson University. After a bit of explanation about MY motivation (“what IS a master naturalist, anyway?”), we quickly delved into the nitty-gritty details about stormwater, runoff, and the importance of managing dust (which becomes silt in the water). It turns out that most of my interests – and much of the painstaking environmental protection that happens during highway construction – are related to water quality and quantity.
The rectangular holding ponds that you see on the roadsides as you drive along the project’s length are called wet swales – they are terraced, cascading water collection devices, designed to fill up and spill over to the next one just slightly lower. This process continues, with each separate holding area doing its part to clean the rainwater and even to cool it (reducing its “thermal charge”) before it finally returns to deeper drains and, eventually, to the creeks along the highway’s path. Here’s what they look like before the construction teams hydroseed and plant native flowers and grasses.
Highway construction has become a much more environmentally safe and savvy operation in the past few decades. The use of large artificial ponds has been superseded by these wet swales, which in turn become bioswales. At the end of the cascading run of wet swales, the contractors use gabions (those chain-link cages of riprap rocks) as a final protection to the waterway; these are removed a year or so later, when the environmental inspector deems the water returning to the natural water sources to be of appropriate quality.
In less than a year, the process has created a sort of natural succession – grasses and flowers come up, and the critters return. We saw bunches of tadpoles and insects darting among the wet swales and were pleased to catch sight of a Least Bittern feeding at the edge of one of the swales (the cattails are volunteers as well, although the Rudbeckia is part of the plantings done by the construction teams).
Our next stop was Norwich Creek, one of the larger streams that the highway traverses and home to the dwarf wedgemussel (Alasmidonta heterodon), which is classified as “rare and restricted.” Thus, any construction near Norwich Creek must follow stricter regulations, including limits on the time of year when construction can be conducted, no use of larger equipment, and no activity within 20 feet of the stream banks. The dwarf wedgemussel, rated as “endangered” on both federal and state lists, is a tiny species found primarily in only eight locations in the U.S., and four locations in Maryland, including Norwich Creek. The dwarf wedgemussel is fascinating, as it requires an intermediate host fish (notably the tessellated darter) for larval development and metamorphosis. Excess runoff from agricultural fields and silt from poorly managed stormwater are considered the main contributors to the loss of appropriate habitat and thus the endangerment of these mussels.
One of the strategies to protect a creek is to have new bridge designs that have little or no impact on the waterflow, either during construction or afterward. Compare the picture of the 1982 span over the Norwich creek, which shows that support pilings were placed directly IN the creek, to the current approach, which has a 120’ span through which the creek runs unimpeded and undisturbed. When we walked below the bridges to take a look, there were turtles in the water, and the whole area is protected with silt barriers.
Norwich Creek Bridge, 1982 span
Norwich Creek Bridge, 2017 span
Which reminds me to report on how impressed I was by the various checks and balances in place for this project and, by extension, for other construction projects throughout the state. Starting with federal National Environmental Policy Act (NEPA) requirements, often considered a decade or longer before construction starts (the 404 Widening project work started in 1989 with these requirements), there are ongoing guidelines to be followed and harsh penalties assessed if violations are found.
One of my hosts, Duncan Kerr, serves as the independent environmental monitor. He takes pictures at different sections of the project and makes regular reports, noting whether the contractors involved are following the approved plans and permit requirements (all of which were in giant notebooks in the conference room where we met as well as in the contractors’ offices in an adjacent building).
Gerry Hammel, the regional environmental coordinator, monitors the contractors’ work, producing quality assurance reports each week that are graded from A to F, based on a series of online checklists that Gerry can use in the field. Because the 404 Widening Project is under tight time constraints, Gerry visits daily rather than weekly. Everyone is happiest when the grades are A or B, but any lower grades result in swift action – a grade of C permits the contractor to address the issues as soon as possible; a grade of D stops all earthwork immediately, even on separate sections of the project; and a grade of F stops ALL work on the project until the issue is rectified. Fines are also levied – on the order of $8,260 per day! Obviously, the contractors want to avoid these problems, and they seem to quickly realize that the state of Maryland is serious about protecting the environment where they are working.
We also talked about mitigation – how to minimize the impact of a construction project after the work is done, the big equipment has moved on, and the traffic is flowing normally. There are a number of different levels of wetland and forest replacement, all governed by various federal and state regulations (as you might imagine, there are monthly meetings on a project like this, with the U.S. Army Corps of Engineers, the Maryland Department of the Environment, and the U.S. Fish & Wildlife Service, as well as other stakeholders). To protect against erosion and extra sediment flying around and ending up in the creeks and waterways, all large dirt piles that will be exposed longer than three days must be covered or seeded – so you’ll see greenery sprouting from those huge piles of sandy soil by the edges of the project. Because the Tuckahoe Creek is tidal, the project by the creek is part of the Chesapeake Bay “critical area,” and every tree taken down for the construction must be replaced in a 1:1 ratio. Some of the wetlands along Route 404 were protected in situ and are considered “permanent mitigation.” And, to help replace the trees taken down in the Caroline County section of the project, the Maryland SHA purchased a 107-acre lot in Goldsboro on which three types of wetlands habitats will be recreated: forested, scrub shrub, and PEM (Palustrine emergent).
Overall, this experience has left me with a new appreciation for the whole project – the environmental protections in place are actually being followed, and the engineers and project managers are friendly, deeply knowledgeable about their craft, and passionate about leaving a site better than they found it. I am very appreciative of their willingness to share their time and expertise with me.
by Beth Lawton, Maryland Master Naturalist
Maryland State Highway Administration website for the 404 Widening Project: http://www.md404project.com/
Encyclopedia of Life entry for the Dwarf Wedge Mussel: http://eol.org/pages/449672/details#size
Nice site for details about the dwarf wedge mussel: http://www.conservewildlifenj.org/species/fieldguide/view/Alasmidonta%20heterodon/