Green stormwater options weighed
Bellport Village officials are considering installing a bioretention field in two proposed locations as a possible solution to address stormwater drainage.
At a work session Monday night, Carrie O’Farrell, resource and wetlands assessment director at Nelson, Pope and Voorhis Environmental, presented the board with information on bioretention fields — otherwise known as rain gardens — along with benefits and challenges.
According to Mayor Ray Fell, the village received $475,000 in grant funding, aided by Sen. Tom Croci (R-Sayville) and Assemb. Dean Murray (R,C,I-East Patchogue). After receiving approval in August 2016, the village must now examine the scope of the work, come up with a design plan and projected cost, and send that information back to the state for final approval.
The grant monies will be used for two projects: installing new catch basins at the village highway yard, and a to-be-determined solution for Thornhedge Road. One possible option is a rain garden, O’Farrell explained. Before delving into details, she gave an overview of stormwater drainage in the village, as well as two additional project proposals for which no grant money has been awarded yet.
According to O’Farrell, there is a large drainage system along Bellport Lane and the engineers were asked to look into possible improvements that would pull some of that water “offline” and treat it. On the north side of the village, O’Farrell said, the parking lot across from village hall would be an ideal location based on the depth, to groundwater being larger than it is further down the road, closer to the bay.
Fell wondered what that project would involve and how it could help alleviate stormwater and runoff rushing into the bay. “The bypass will allow water to divert,” O’Farrell said, adding that it would not accommodate the entirety of the system, but would be designed to hold at least the first inch of rainfall during a storm. “It’s not a lot, but still good since a lot of pollutants fall during that initial rainfall,” she said.
Still, the village would need to look into other ways to divert the flow off of Bellport Lane.
“As you come down the hill, you lose elevation and ability to recharge,” O’Farrell said. Village clerk John Kocay also pointed out that at those lower elevations, the groundwater below fluctuates. “When [Trustee Mike Ferrigno] and I looked, it was dry, but as the tide changed it filled with water, so it’s very much in flux each day,” Kocay said of an observation made during a previous excavation.
The porous soil and sand means water comes up just as fast as it goes down, O’Farrell explained. Those design constraints point to rain gardens as a possible solution. “[Rain gardens] are a surface option and meant for water quality improvement more than anything else,” she said.
Catch basins already exist at the intersection near Bellport Lane and Osborn Park. They would be used to collect water and “bubble” it out into a vegetated area, the rain garden. “The idea is to pull water up, and through biological uptake get rid of pollutants,” O’Farrell said.
A colleague of O’Farrell has a wealth of experience with designing rain gardens after working in Minnesota — the land of 10,000 lakes. “They have poor soil conditions and lots of water-quality issues,” she explained, noting that the state required action be taken nearly two decades ago. “So he has experience with design in terms of what works and what doesn’t,” she said.
If designed well, the rain garden would blend in as a landscape feature and would not change the use of the park,” said O’Farrell, adding that they have worked with private residents to install them on their properties and with golf courses as well. “They can be gorgeous,” she said. “But there is nuance to how it is done. Like any garden, you have to weed it twice a year, put in mulch or rocks and other things to make sure that through longevity, it looks good.”
The drain connecting the basin to the garden would also have to be routinely cleaned, as a normal street drain would.
Trustee Mike Ferrigno raised a concern about how residents would react. “The village has spent tens of thousands, both razing that park and putting a water system in,” he said, estimating that nearly $40,000 has already been spent there. “It’s going to be difficult to sell this to residents to tear all of that up for a rain garden,” he said.
“Water is coming down this hill no matter what,” O’Farrell said, adding that the entirety of the park would not be disrupted. She also explained that an additional benefit to the rain garden would be tackling pathogens, which would be filtered out through biology.
Ferrigno pitched the idea of putting the garden on the north side of the village in the municipal parking lot. According to O’Farrell, Chis Voorhis looked into that location, but thought the slope would be an issue. “We thought the park location would be better based on the existing natural topography that pulls the water in that direction,” she said. The pitch of the roadway along Bellport Lane was also a concern, she said.
Kocay passed around photographs of other bioretention systems in Brookhaven, including one in Brookhaven hamlet and one in East Patchogue, that have gone awry due to a lack of upkeep.
“We would need a commitment of maintenance,” he said.
However, the top issue for Kocay and the board was the future of mandates from Albany. “Are these short-term solutions for something that might be coming down the pipe that are more expensive and more conclusive?” he asked.
According to O’Farrell, all DEC stormwater programs are regulated from the top — the EPA sets the rules. “With a change of administration, things change. At the EPA level, this outlook might change,” O’Farrell said of current regulations. Regardless of the future, O’Farrell said projects like this would still be improving the baseline at the end of the day. “There’s always benefits in doing them, but given the state of the EPA, I have no crystal ball of what will happen,” she said.
Kocay expressed concern that because the village is a small municipality, these large projects are a risk to take on.
“If you can get them funded now, it’s that much less that you’re doing when the mandate goes in and everybody’s going after the money,” O’Farrell said of being ahead of the game.
“We might feel like these numbers are a challenge, but it might be 10 times that down the road,” said trustee Joe Gagliano, citing the possibility of a future Sandy-like/Sandy-esque storm. “And there’s maintenance to everything,” he said, adding that he thinks the rain garden is the best bet.
As the village board continues to grapple with what to do on Thorn Hedge Road, Fell said the next step would be to discuss this with residents and get feedback. He said he would also like to see a preliminary design plan so the board has a better understanding when they do approach the community.
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