An illegal sewer connection at a Beach Road property overwhelmed a nearby town-owned pump station during last Thursday’s intense rainfall, causing hundreds of gallons of sewage to be discharged into the Vineyard Haven harbor as a malodorous stink lingered for hours.

In interviews, Tisbury department of public works director Kirk Metell and town administrator Jay Grande said the town building department had ordered the removal of the illegal connection, sump pump and related plumbing, located at 25 Beach Road, within two days. The building department will enforce the disconnection.

Mr. Grande and Mr. Metell said no fines had yet been issued for the illegal connection, although they said monetary penalties could be forthcoming. The state Department of Environmental Protection (DEP) and the town have the authority to levy fines for illegal sewer connections under Title V, the state sanitary code.

The discovery of the illegal sewer connection, which comes after a similar illegal connection was identified at the Mansion House hotel last year, has prompted a town-wide investigation focused on the low-elevation Beach Road area, for additional illegal sump pump connections, Mr. Metell said in response to questions from the Gazette.

“We’re going to be going pretty much door-to-door on our collection systems to make sure there’s not anything else hooked up illegally . . . especially in the low-lying areas that have water infiltration from groundwater,” Mr. Metell said.

Under state law, it is illegal to pump clean groundwater into town sewage treatment facilities through sump pump connections. But many buildings in the often heavily-flooded Beach Road district have sump pumps to remove water from flooded basements, and diverting the water to leaching fields or catch basins can be costly and logistically difficult.

“You know why people have tied in, because where’s that water going to go?” town administrator Jay Grande said. “In this case, it was just overwhelming the system.”

Some 300 gallons of sewage were discharged into Vineyard Haven harbor; the source of the problem was traced to an illegal sump pump at 25 Beach Road. — Ray Ewing

Heavy rain fell heavily for much of the day last Thursday, causing dramatic flooding along Beach Road and the Five Corners intersection. The National Weather Service station in Vineyard Haven recorded 3.14 inches of rain.

According to interviews and a report prepared by the town DPW, town officials responded to the area at approximately 2:30 p.m. on Sept. 9 after receiving reports of a “strong odor” emanating from the area of Art Cliff Diner and the Citgo station. Wastewater staff, including Mr. Metell, superintendent Jared Meader and lead facility operator Mike Albercine, investigated the scene and noticed water coming up from the town grinder pump located at 19 Beach Road. The grinder pump is a waste management device used to pump sewage from buildings to the municipal treatment plant. The pump services a variety of businesses along Beach Road, officials said.

But the influx of water had caused the grinder pump to fail, submerging the chamber and forcing wastewater staff to operate it manually, Mr. Metell said. The report estimates that 300 gallons of sewer overflow discharged from the pump.

“With the extra influx of fresh water coming in from the sump pump, it raised up to a level where it caused a mechanical failure on the pumps themselves, and then it overflowed onto the ground,” Mr. Metell said.

By 3 p.m., staff, with the assistance of Maciel & Son’s septic haulers, had stopped the grinder pump overflow but noticed that “a large volume” of water was still flowing into the system.

Hours of detective work ensued to identify the nature of the flow, according to the report, with town officials and Troy Maciel using CCTV cameras and Title V property maps, eventually sourcing the problem at 25 Beach Road, the location of Ackee Tree Caribbean American Grocery Store. The property is owned by Vineyard Beach LLC, a company based in Dedham that lists John Salvatore, Greg Salvatore, Michael J. Yanoff and Eric S. Slifka as managers.

“While Troy and his crew were cutting the driveway, we started suspecting that there was an illicit [sump pump] connection attached to the system because the flow was increasing and decreasing in a fairly steady pattern,” the report states. “After gaining access to the solids tank, we again used CCTV and confirmed the flow was coming from 25 Beach Road.”

The crew then worked for an additional three hours to locate the pump, eventually finding it in a crawl space, hidden under a rug and trap door, according to the report. The property was disinfected using a bleach mix the next day.

“There could be a fine assessed, but the most critical thing was ordering it to be disconnected,” Mr. Grande said on Tuesday.

Town officials did not have further details on how long the illegal connection had existed before its discovery last week. “We’ve never had an overflow in that area before,” Mr. Metell added.

With its sewer treatment plant near capacity, the town has begun a comprehensive wastewater management plan, looking to add capacity and increase sewer connections along the State Road business corridor to mitigate nitrogen pollution in the Lake Tashmoo watershed. But the low-lying Beach Road district continues to be an issue for the town, as development proposals for the area mount, storms strengthen and sea levels continue to rise.

Mr. Grande pointed to a series of steps the town has taken to address the issues, including a drainage project on Beach Road Extension and the purchase of equipment to monitor sewer flow.

“We are going to biannually audit the system for inflow and infiltration,” Mr. Grande said. “That’s the discussion we had Monday morning.”

The town building department could not immediately confirm Wednesday morning whether the illegal sump pump had been disconnected.