The Lagoon Pond Well, the source of the bacteria that caused the Oak Bluffs boil water emergency in late June, went back online on Tuesday, August 6, according to officials from the Oak Bluffs water district. Installation of a temporary chlorination system was completed at the wellhead on July 30, and all subsequent tests have met Department of Environmental Protection (DEP) standards.
The well had been offline since June 24, after routine tests showed an elevated level of enterococci, a bacteria that indicates the probability of harmful bacteria, in the town water supply. The water district eventually identified the Lagoon Pond well, one of the largest sources of water in town, as the source of the bacteria.
No Oak Bluffs residents became ill from contaminated water, however, the DEP boil water order caused considerable disruption to residents and to business owners, just as the tourist season was kicking in. Although the exact cause of the contamination is still not certain, officials said it was most likely caused by exceptionally heavy rains combined with a spike in water usage, which created a vacuum that sucked groundwater into the normally reliable well.
“The Lagoon Pond well is unique,” said water commission consultant Larry Bombara.
“Most of the wells on the island are deep but this is a spring fed well and the the aquifer is close to the surface, and that adds to it’s susceptibility.”
The Lagoon Pond well started pumping in 1884 — it is the oldest municipal well in operation in Massachusetts.
The well pumps approximately 560 gallons of water per minute. Even though it was out of operation in July, the Oak Bluffs water district still pumped 59 million gallons for the month — an all time record.
“Moving forward, we’ll be more cognizant of weather conditions, and the well will be tested twice a day,” water commissioner Kevin Johnson said.
The current chlorination system is only a temporary measure. Request for proposals (RFP) for a permanent chlorination system went out this week. Permit applications will be submitted to DEP by November 15, and a contractor will be chosen by the end of the year.
“I’m comfortable we’ll be ready by next spring,” Mr. Bombara said.