Editor's note: All over the watershed, water engineers are evaluating dams and how they affect the flow of water. Sometimes local people are fond of the way it is now (as it was for the Columbia Dam on the Paulins Kill.) Other times there's some confusion about the benefit because at first the "before" looks a lot prettier than the immediate "after." In time, the after will look just fine and the ecosystem will rebound to its natural state -- a big plus as we begin to feel the effects of climate change and the way heavy rains lead to flooding where there hasn't been flooding.
Lots of small streams flow through the Delaware Water Gap National Recreation Area, which straddles New Jersey and Pennsylvania as well as the Delaware River.
Before there was a park, this land was worked by the people who lived here. They created many low earthen dams to control where the water flowed. The National Park Service/Delaware Water Gap National Recreation Area has been working to improve the ecosystems of Van Campens Brook, near Millbrook Village, on the New Jersey side of the river.
According to Frank Dale in his article “Mill Brook Days,” published in Skylands Visitors, “the village is a re-created community of the 1800s where aspects of pioneer life are exhibited and occasionally demonstrated by skilled and dedicated docents throughout the village.”
If you visited Mill Brook Village in the summer, you could see bright orange construction fences and some construction equipment through the trees. Although it might look like a construction site, the National Park Service is not building a strip mall or apartment complex. It is deconstructing four low earthen dams and old dam remnants to restore wetlands to the park.
According to Kristy Boscheinen, the NPS Watergate Wetlands Restoration Project manager: “The project will allow Van Campens Brook to flow naturally within its floodplain. The floodplain also includes wetlands and having that stream-floodplain-wetland connection is a positive thing for the environment.”
Once upon a time, dams were built to force the water to “behave” on a convenient path that sometimes included the elimination of wetlands. According to the Environmental Protection Agency, “Wetlands are important features in the landscape that provide numerous beneficial services for people and for fish and wildlife. Some of these services, or functions, include protecting and improving water quality, providing fish and wildlife habitats, storing floodwaters and maintaining surface water flow during dry periods. These valuable functions are the result of the unique natural characteristics of wetlands.”
Time and research have taught us that it’s better when possible to let water flow where it wants naturally, to prevent further flood damage, which is the purpose of this project.
Finalized in 2020, the NPS’s proposed dam deconstruction will attempt to reverse human-made damage — specifically from the construction and maintenance of high-voltage transmission lines (electrical lines) while simultaneously strengthening the riverbanks with new vegetation.
By removing the man-made infrastructure — the dam and road — Van Campens Brook will be able to access its natural floodplain, a lower piece of land that the brook can empty into when there are heavy rains and flood events.
Properly designed (water way) connections allow for the diversion of floodwater (to flow) onto floodplains,” wrote Kevin F. Noon in a case study on the project. Noon works for the Water Resources Division of the National Park Service.
After reconstruction, the Van Campens Brook will no longer fill connecting streams during storms and so will prevent excess water going downstream. And that will further reduce damage caused by the high force of the moving water and reduce the flood damage risk to the downstream trails, bridges and natural resources.
The dam removal will also benefit the wild wood turtle and trout. Because of the increase in wetlands, wood turtles will thrive in the wetland meadows. And with the new water pattern, there won’t be warm water ponds and trout will thrive in the cooler water.
The cooler water will also help prevent the spread of invasive species like the rusty crayfish. Shrubs also aid in preventing invasive species by shading the water from predicted heat-waves caused by climate change.
Most of the buildings in Mill Brook Village will be untouched by the restoration work: Two buildings are expected to be impacted —the Mill Brook School, a one-room schoolhouse, and Garis Barn.
Garis Barn will have the lower clapboards on the barn removed which “will allow floodwater to flow through, instead of against, the barn and prevent the buildup of rocks against its sides,” explained Boscheinen. Also, she explained the NPS is hoping to keep the barn in place and not relocate it to the village a half-mile away. (Moving the barn would cause it to lose its historic value.)
Despite the improvements, it is expected that the barn will eventually fall down. Improvements from the project will slow the process. Through documenting photographs, profile drawings, and maps, the NPS is determined not to lose the barn’s history.
The barn and school will not be moved as they have already faced flood damage. During major flood events between 2004 and 2011, the Van Campens Brook pushed several tons of river rock up against the buildings and Columbia Walpack Turnpike, causing the area to be mostly inaccessible and at this point only visited by anglers.
By leaving the already damaged buildings, the floodplain water will flow through the buildings reducing the force of the water downstream. It is unclear how long the buildings will stay standing, but the rest of Millbrook Village will continue to thrive.
While we may be losing some buildings, Noon reports the new flood pattern will allow for “spring seeps, wetland meadows, and forested wetlands.” The goal of the NPS is to plant shrubs and evergreens that are native to Pennsylvania.
Overall, the increase in floodplains will benefit the ecosystem by returning the Watergate Restoration site to its natural wetland state. Within the next five years, visitors can expect an increase in fish at their favorite spots, wetland meadows will decorate the area, and visitors will be able to experience an increase of water bank critters, “raccoons, muskrats, mink, beaver and if you're lucky enough, you might even see some otters frolicking along the bank.”