The Center for the Inland Bays (CIB) has received a $98,000 grant from the Department of Natural Resources and Environmental Control (DNREC) and the Clean Water Advisory Council to begin implementation of stormwater retrofits for the Anchorage Canal drainage area. The grant will allow them to start the study, design, engineering and construction of a particular wet swale along South Pennsylvania Avenue in front of Sea Colony. It is just one of many projects proposed for the area. Several other retrofit projects in the area have been proposed, with different price tags attached.
The CIB invited the public to hear and comment on the plan to clean up polluted stormwater from Route 1 that eventually makes its way to the Anchorage Canal in South Bethany. Last August, teams consisting of members of the CIB and the Center for Watershed Protection, DelDOT employees, engineers and interested citizens canvassed the neighborhood by car and by boat, looking for retrofit opportunities.
The Anchorage Canal is the northernmost canal in South Bethany and connects to Little Assawoman Bay. Its drainage area is 125 acres, of which 55 percent is impervious cover (including blacktop, asphalt and other types of cover that does not allow for filtration of the water).
Areas of Coastal Highway and its western commercial strip, as well as portions of the Sea Colony high rises, Middlesex Beach and the town of South Bethany drain into the canal. According to the CIB, studies show that high levels of nitrogen, hydrocarbons and sediment enter the canal, which produces runoff even during light rains, which in turn means poor canal conditions in unhealthy levels of dissolved oxygen, bacteria and algae blooms, as well as concerns about the water quality in the Little Assawoman Bay itself.
“That was our first meeting about that project,” said Chris Bason of the CIB, adding that they are continuing to raise funds for the improvements. They chose the project at Sea Colony because it was a logical place to start comparing investment to return, he said. “We prioritized and those at the top [were because] for their cost, they removed the most pollution and were the most feasible.” Bason said the next project could possibly be retrofitting the median strips on Route 1.
Greg Hoffman, an engineer with the Center for Watershed Protection, presented plans and explained that, in the simplest terms, retrofitting is “putting storm water management in places where it didn’t exist before.”
In addition to retrofitting as a restorative practice, he explained, there are also educational opportunities for the area communities, about illicit discharge prevention, general good housekeeping and pollution prevention, and he explained that stormwater management retrofits have multiple benefits, including beautification and less flooding.
Because construction in the area ultimately happens where there are already houses and roads, and utilities, as compared to a new development with a blank slate, and sometimes there is a need to acquire land in the process, stormwater retrofitting can come with its challenges, but Hoffman and other engineers presented their plans to meet the goals of reducing nitrogen and phosphorus by 40 percent and bacteria by 23 percent, which were set by the State of Delaware using several different plans for different areas.
In addition to the swale project that will be implemented first, the CIB this week presented ideas for retrofitting the median, which, according to Hoffman, is one of the more desirable places to start because it is surrounded by lots of impervious surface, sits low and is public land.
“It wouldn’t take too much to excavate the middle to allow water to filter before it goes into the canal,” he said.
After that, low-maintenance native plants could be planted into the median to allow for better filtration before the water eventually ends up in Anchorage Canal. Other ideas include taking up the gravel near the parking meters on Pennsylvania Avenue, or taking it up and putting it back in an un-compacted form. There are also other opportunities near the commercial areas, where businesses could get involved.
Hoffman said there is “no silver bullet” but said next steps include discussing the proposal with the appropriate communities, county and state officials, collecting additional information to develop bio-retention designs, having a pre-application meeting with government officials, using information gathered from that meeting to finalize construction plans, and submitting plans to the appropriate agencies.
Bason said it was a good opportunity to get everyone together and talk about the projects. He added that they will continue to meet to talk about implementation and funding strategies.
“The communities have given a great deal of time and energy, but so far little cash,” he noted. “The communities are supportive and are working with us. It’s important that they are satisfied and on board and happy with what we come up with and everyone is comfortable.”
The Town of South Bethany has taken the “education” part of cleaning up the canal to heart and just recently, after two years of working on it, passed an ordinance pertaining to impervious surfaces. The ordinance requires that at least 55 percent of any required setback area be covered with pervious materials; requires that only pervious material is permitted within 5 feet of the property boundary line (or at least 50 percent of the required setback where the required setback is less than 10 feet) on any building lot; and requires advance approval to install impervious ground covering on building lots.