Swampscott/Lynn King's Beach UV Pilot Reveals Promising, Inconclusive Results

SWAMPSCOTT, MA — This summer's UV light-treatment pilot program at King's Beach in Lynn and Swampscott showed promise in cleaning the water, while more data is needed to determine ultimate effectiveness and viability under a wide range of tidal conditions, as part of the Kleinfelder engineering firm's report presented to the Swampscott Select Board.

While bacteria levels were lessened during UV treatment factors, project manager Courtney Eagan allowed that other factors may have contributed to the results, and more work is needed to determine whether those results can be duplicated over the long term and with varied weather cycles.

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Swampscott officials also noted that the results showed that the town's pollution levels were significantly less than those secured on the Lynn side of the culvert, with or without the treatment, while nearby residents again voiced concerns about the noise this summer that Eagan allowed was higher than anticipated when the project was first conceived.

"Not to miss the headline here," Select Board member Doug Thompson said, "but what this (data) graph is showing is that the UV did dramatically decrease the bacteria."

"It decreased the bacteria, yes," Eagan responded. "It does bring it down, absolutely. ... Given the unit that we had, it does seem like it was able to reduce it.

"This is a good start. I think everyone says: 'Oh, yeah, no problem, UV will work.' I've seen cases where it doesn't. Dry weather or not. It really depends on the makeup of the water that is coming at you."

She said it was expected that significant rainstorms would interrupt the response, but that they were encouraged by how quickly the bacteria levels came down after the storms, which were sparse this summer.

Conclusions were that UV light could be an effective treatment for water flow from the culverts, including Stacey's Brook, that effectiveness is reduced during wet weather — particularly in the first 24 hours of a storm — and that UV light reduced the amount of closures on King's Beach this summer.

It also concluded that "numerous operations and maintenance challenges need to be considered in the design of a permanent facility."

"The lessons learned gave us a lot of considerations that could be made in the design of a full-scale or a permanent facility if that were to move forward," Eagan said. "We're not suggesting that necessarily. But we think a lot of those challenges could be overcome."

Next steps, and costs, include recommendations for $153,000 for additional data collection — including in year-round and wet weather conditions — $96,000 for site screening and permit reviews for a potential permanent facility, and $168,000 for site selection, concept design and other aspects of putting a treatment facility online.

The most vocal critics of the pilot program were often nearby residents who charged that it far exceeded acceptable state levels of noise pollution that was incessant throughout the summer.

"We did look into the quietest generator sets we could rent within the time frame that we had for the pilot," Eagan said. "That is what we were able to find. We looked at several different vendors. They all had enclosures. We also sound-blanketed every piece that we could or as much as we could of the genset enclosure, as well as the pumps.

"But, admittedly, obviously, it was higher than what we thought. We tried to take as many measures as we could."

(Scott Souza is a Patch field editor covering Beverly, Danvers, Marblehead, Peabody, Salem and Swampscott. He can be reached at Scott.Souza@Patch.com. X/Twitter: @Scott_Souza.)