There’s no question that this has been a steamy summer so far, and with all the heat and humidity, a dip in a local pond or lake has taken on extra appeal.
But with the ongoing heat — and the frequent violent storms it has produced — comes questions about the quality and safety of the water in that swimming hole.
The state does have a website listing the water quality and safety of all registered public beaches, available online at tinyurl.com/y5fvydh5, where anyone can check the water safety before venturing out.
However, after a Reminder Publishing staff writer traveled to a lake that was deemed safe on the list earlier this month, only to find it closed for water safety issues, we reached out to the state Department of Public Health to inquire about the monitoring system, and how reliable the online information truly was.
Below are the questions Reminder Publishing posed, and the answers, provided by Omar Cabrera from the Office of Communication for the Massachusetts Department of Public Health:
How often are results submitted to the website, and how often is the site updated?
The testing frequency at swimming beaches in Massachusetts varies from beach to beach. Depending on the beach, water is tested anywhere from daily to monthly. The majority of beaches in Massachusetts are tested once a week following sampling frequency guidelines from the U.S. Environmental Protection Agency. Testing frequency depends on how likely the beach is to have water quality issues. Low-use beaches or beaches with few, if any, water quality issues are tested less often. High-use beaches or beaches with historic water quality issues are tested more often.
Beach water samples are tested at accredited laboratories using laboratory methods approved by U.S. EPA. The laboratory testing takes about 24 hours to perform, so water quality results are typically reported the next day.
Local municipalities are required to report beach closures to the Massachusetts Department of Public Health within 24 hours of receiving a water quality violation. This information feeds into the DPH Interactive Beach Water Quality Dashboard (see link above), which refreshes every day, including weekends, at 9:30 a.m. and 12:30 p.m.
Is it better to check with the local health department of the city or town where the beach is located to obtain the most current information?
The dashboard is updated twice daily and is an excellent resource for monitoring beach water quality. If the water body is owned and operated by a local municipality, the local health department receives the results first and reports any closure to DPH.
When we looked at some beaches in our circulation area, we found both a red and a green square on the results tab, but without a clear indication of which result was the most current. Were we reading the information incorrectly?
The dashboard updates twice a day at 9:30 a.m. and 12:30 p.m. and requires a collaborative approach between DPH and local boards of health that report data to DPH. When a beachgoer visits the dashboard, the default view is the “See All Closures” tab, which contains a list of all closures DPH is aware of; but there are two other tabs that contain excellent information: the “See Test Results” tab and the “See All Beaches (Map)” tab.
The “See All Beaches (Map)” displays an interactive map of all beaches in Massachusetts, represented as colored dots on the map. The color of the beach corresponds with the current status of the beach, where green indicates an open beach, red indicates a closed beach, and orange represents a partially closed beach. Some of the larger beaches in Massachusetts can have a partially closed status if one end of the beach has poor water quality, whereas the other end has safe water quality. These colors can change when the dashboard refreshes at 9:30 a.m. and 12:30 p.m., but otherwise, one beach will never show two different colors simultaneously.
The “See Test Results” tab allows one to select a beach and see all single sample results as well as the geometric mean over the previous five weeks. One can hover over any blue area on either chart to view the bacterial result associated with that date. Both charts display the safe limit for bacteria as a red-dotted line across the graph to compare against the sample results.
Given the high heat conditions this summer, are blue-green (cyanobacteria) algae blooms — a danger to humans and pets who enter the water where they occur — more prevalent this season?
In general, extended periods of hot, humid weather can result in conditions that are more conducive to the formation of a cyanobacteria harmful algae bloom (HAB). In addition, intense rain events can increase storm runoff, and therefore nutrients, into bodies of water and lead to a higher likelihood of blooms.
Given this possibility of cyanobacterial blooms, what should people look for when planning to swim in a local lake?
The following information is from the DPH “Harmful algae blooms in freshwater bodies” factsheet.
How does someone know if there is a harmful algal bloom in the water?
Cyanobacteria can cause the water to appear slightly discolored, cloudy or resemble pea soup or paint. Typically, blue or green, HABs can also be brown or red and can give water a bad odor. In some blooms, cyanobacteria are dispersed throughout the water. In contrast, in other blooms, they are concentrated in a scum or mat, either on the surface of the water or in sediment along the shoreline.
How are humans and animals exposed to cyanobacteria?
People and animals can be exposed to cyanobacteria through direct skin contact, ingestion, or inhalation. Those using the water for active recreation (like swimmers or jet skiers) or for drinking are most likely to be exposed. Children and pets, who are more likely to get these bacteria in their mouths, are of special concern. Dogs can become very ill and even die from licking cyanobacteria off their fur.
Cyanotoxins (if present) are usually contained within the cyanobacteria cell. When the cells die, the toxins are released into the water, where they can be ingested. Cyanotoxins are not absorbed through the skin.
What should people do if they suspect a harmful algal bloom?
When in doubt, stay out!
If you see a possible HAB, avoid contact with the water.
Contact your local health department if the bloom is at a recreational waterbody. If the suspected bloom is at a drinking water reservoir, contact the local water department and the Massachusetts Department of Environmental Protection.
What precautions should a person take for themselves or their pet if they accidentally encounter a blue-green algae bloom?
DPH’s recommendation for all individuals is, “when in doubt, stay out,” — avoid contact with the water whenever you see a possible harmful algae bloom.
If contact occurs, wash yourself and your pet with tap or bottled water. If you or your pet swallows water, call your doctor or veterinarian. If you believe you or your pet is experiencing adverse health effects, contact your doctor or veterinarian immediately.
