The first sampling of the Great Herring Pond Beaches for E. coli in late June showed little bacterial contamination, assuring a healthy July 4 week swimming experience. Sampling on July 25th also indicated very low levels. Another sampling will be collected at the end of August.

Despite the several indicators that we may not have a cyanobacteria problem this summer, we were issued a Cyanobacteria Advisory. We were greatly surprised by this development for several reasons. First, GHP is unusually clear for this early in August. Second, samples taken at 4 locations where the cyanobacteria have been sighted in the past, have been taken monthly in April and May and every 2 weeks in June and July. Fluorometer readings that measure a UV-active chemical emitted by cyanobacteria had been increasing somewhat but are still low. Third, total phosphorus measurements have been relatively low in Great Herring Pond. Fourth, a small surface sighting in Eagle Hill Cove dissipated within hours, mimicking observations in pre-bloom years. We think that in certain coves, when the wind and the water are calm, conditions can favor local formation of cyanobacteria, which then are mixed and dissipated. At the same time, no cyanobacteria were seen anywhere else in Great Herring Pond. The water sample taken on July 17 sent for cyanobacteria evaluation found a low number of cyanobacteria and no microcystin toxins.

When small clumps were reported in both Great Herring and Little Herring Ponds early this month to the Health and Human Services Department, they were obligated to issue the Cyanobacteria Advisory even though there were no other reports of cyanobacteria in any other spots in either pond.

Samples will be taken on Monday, August 11.  Test results will be available in about a week.  If they do not show cyanobacteria or toxins, the Advisory will be lifted.

Thanks to all of you who do not throw lawn waste in the pond, refrain from clear cutting, regularly pump septic and cesspools, pick up animal waste in your yard, and don’t use fertilizers and other chemicals near the pond. These practices all help prevent the flow of phosphorus into the ponds and reduce the blooms.

All summer the low water level in Great Herring Pond has been a concern. We have contacted the State Dept. of Fish and Wildlife which controls the flow of water out of GHP, and staff at Bourne who also are involved, many times this summer and continue to urge them to allow more water to stay in the pond. Unfortunately the hot dry weather has not helped.

Meanwhile, with the help of our experts, we are evaluating more options to find ways to remove excess phosphorus to solve the cyanobacteria problem. Michelle Christensen and I have been chosen as members of the Comprehensive Wastewater Management Plan committee that will seek to develop a Plymouth plan for future wastewater treatment. While sewering is an obvious solution, it is expensive and will likely take a while to implement. 

We will provide you with updates throughout the summer and fall.