CHATHAM – Toxic algae has closed several freshwater ponds on Cape Cod in recent years, including Harwich's Hinckley's Pond in 2009. So far Chatham's ponds have not been impacted, and a new testing program aims at providing a warning if that changes.
Volunteers are being sought to help collect water quality samples from five ponds this summer. Testing for cyanobacteria – the organism that causes the blue-green algae blooms – is being added to a freshwater pond testing program begun by the Friends of Chatham Waterways in 2013. The program is part of FCW's Water Watchers salt water testing program, which is now in its 20th year.
Working with the town's department of natural resources, the program aims to provide advance warning of a cyanobacteria breakout, which can be harmful both to the pond environment as well as the health of people and pets. Like the degrading of salt water embayments along the coast, the increase in algae blooms in freshwater ponds is the result of nutrient loading from septic systems, lawn fertilizers and stormwater runoff.
“There's been a lot of concern about it in other places in recent years,” said Dr. Robert Duncanson, director of the natural resources department. “It has not been a problem [in Chatham] that we're aware of.”
Some elevated cyanobacteria levels were found in Lovers Lake and Stillwater Pond some years back, which was among the reasons those ponds were treated with alum. While the waters haven't been monitored for cyanobacteria since then, anecdotally, at least, there hasn't been any algal blooms, Duncanson said.
According to information supplied by FCW, cyanobacteria bloom usually occur in late summer or early fall and can express as scum or mats on the water surface. Not all algal blooms are toxic, but they nonetheless can harm a pond's ecology.
“Monitoring water quality of ponds can give communities advance warning so they can adequately plan and deal with the adverse environmental and health effects associated with a harmful bloom,” the FCW information states. “The goal of any monitoring plan is to be able to take action before levels are reached that pose health risks.”
The Association to Preserve Cape Cod piloted the program last year in Brewster and will provide training and methodology for the Chatham program. Volunteers will collect water samples from the shoreline using special equipment and protocols on 11 testing dates from late spring through early fall, roughly every two weeks. Water will be tested for clarity, temperature and other conditions. The goal is to recruit eight to 10 teams of two people each.
Ponds to be tested for cyanobacteria are Lovers Lake, Stillwater, White, Schoolhouse and Goose ponds. Others may be added in the future. Any new equipment needs will be covered through the town's existing water quality budget, Duncanson said.
A study and action plan for the town's pond was done in 2003. The town also participates in the Cape Cod Commission's Ponds and Lakes Stewardship (PALS) program, which is augmented by the FCW testing program. Chatham's ponds are, for the most part, in good shape; ponds don't change as drastically or quickly as waters in the marine environment, Duncanson said.
“Ponds for the most part, year to year, are relatively stable,” he said, since they aren't subject to the same current and tidal ebbs and flows as marine waters. Given changes to the environment, however, there's no guarantee conditions won't change.
“Until you actually start looking at it, you don't know,” Duncanson said.
Anyone wishing to volunteer for the Friends of Chatham Waterways pond monitoring program should contact DeeDee Holt at firstname.lastname@example.org.
Email Tim Wood at email@example.com