In mid-January, shortly after the destructive storm of Jan. 13, drivers and walkers who regularly cross the West Harbor Pond causeway noticed that something had changed. The distinctive halo in the harbor, which marks the upwelling of water discharged from the West Harbor Pond siphon, and which is visible in all but the windiest conditions, had disappeared, clear evidence that the siphon was no longer operating.   

The West Harbor Pond siphon was installed in 2019 to replace the original siphon, installed in 1880 when Campbell Cove was dammed to create a pond for harvesting natural ice.  Until it failed in 2008, the 1880 siphon operated continuously, fulfilling its original purpose of evacuating saltwater from the Pond, a task carried on by the 2019 siphon.  The dramatic improvement in the Pond’s water quality brought about by the 2019 siphon is described in the 2021 article to the Register found at this link:  https://www.boothbayregister.com/article/siphon-improves-west-harbor-pond-s-water-quality/143656 

Saltwater enters West Harbor Pond through the box culvert at the west end of the causeway during king tides and storm surges.  For example, during the storm and astronomical high tide of Jan. 13, the water in the harbor came within inches of the top of the West Harbor Pond causeway, and a veritable river of saltwater poured through the box culvert and into the Pond. The multiple king tides that occurred from December through April only added to the quantity of saltwater dumped into the Pond. 

When saltwater, which is heavier than freshwater, enters West Harbor Pond, it sinks immediately to bottom, where it is removed by the 2019 siphon. But when, in mid-January, the siphon stopped operating, saltwater accumulated in the Pond in unprecedented quantities. When the West Harbor Pond Watershed Association (WHPWA) conducted its first monthly water testing of the year on April 14th, it found the saltwater-freshwater interface at a depth of only three meters. The Pond’s water, which, at the 2-meter level, was 101.3% oxygen-saturated (yes, for complicated technical reasons, oxygen saturation can slightly exceed 100%) was only 4.9% oxygen-saturated at the 3-meter depth. By way of comparison, a year earlier, in April of 2023, the saltwater-freshwater interface occurred between six and seven meters, 13 feet lower than this year in a pond whose mean depth is only 15 feet.   

As soon as it realized that the siphon had ceased operating, the West Harbor Pond Watershed Association (WHPWA), which assumes responsibility for the siphon’s operation, set about trying to hire a diver; but, with so much damage to the coastline from the December and January storms, it was unable to do so.

So on April 22, at the WHPWA’s request, Nick DeGemmis, the Boothbay Harbor Sewer District’s new superintendent, and David Pratt, BHSD’s foreman, brought the district’s new, high-pressure water jetter to the dam to try to blow out the siphon, whose outfall, the WHPWA speculated, had been buried in silt by one of the winter’s storms.

The jetter holds 750 gallons of water, and for two hours Nick and David pumped two full loads of water (1,500 gals) into the siphon at pressures from 150 to 400 PSI. They tried various combinations, pumping water into the harbor-side and then into the pond-side pipe, but without success. The characteristic halo failed to appear in the harbor showing water upwelling from the outfall.

But they put the WHPWA in contact with Tim Pinkham, a local diver. On April 28, Tim swam the length of both the harbor-side and the pond-side pipes of the West Harbor Pond siphon. He also replaced the orange buoy marking the siphon’s outfall that had become detached in a storm a couple of years ago. He found no damage to the siphon. Nor did he find that the outfall in the harbor had been buried. Instead, he discovered that the siphon’s intake in the Pond was blocked, something that had never before occurred. With some effort, he was able to remove the obstruction. With the blockage removed, the siphon immediately reestablished itself and by April 29 the halo was again clearly visible. Note: With the siphon restored to operation, there will be no “rotten eggs” odor of hydrogen sulfide, as there was when the siphon began operating in 2019. The vegetative decay at the bottom of the Pond takes years to produce a perceptible odor when the siphon resumes operation after a period of inactivity.