Coventry Lake Health Advisory
July 22, 2022
Eastern Highlands Health District (EHHD), in accordance with State guidance, has issued a Health
Advisory warning cautioning against certain high risk activities on Coventry Lake due to a Blue Green
Algae bloom. Link to EHHD advisory.
This is a first for Coventry Lake. We have been watching the increase in this algae since late last summer.
Typically it dies back during cold weather, but last December the lake was unusually warm, which
allowed continued growth. Please follow the Health Advisory for yourself, and guard your pets.
In addition to EHHD’s information, here are a couple of logistical items to share, and answers to some
Frequently Asked Questions (FAQ’s):
1. Is this outbreak related to Hydrilla treatment? The test samples were taken on the Monday
before the first treatment, so no. Dr. Kortmann, (title), has also conducted research on this
possibility and, at present, there is no research to connect the Hydrilla treatment to this Blue
Green Algae bloom.
2. Did this come in on boats from other lakes? No. This is a naturally-occurring algae in our lake.
3. Are there chemical treatments for Blue Green Algae? Yes there are, but these chemicals also
may affect some of the good natural organisms in our lake. There is also a lengthy permitting
process, so this is not an option for this year.
4. How long will this last? Will it go away by itself? No one really knows how long it will last.
Factors such as temperature and rainfall are involved. Rain can help cool the lake. Blooms
typically go away on their own after a few weeks.
5. How long will the Health Advisory be in effect? It is expected that the EARLIEST the bloom will
go away is two weeks, and the State has an additional one-week grace period. So the EARLIEST
is three weeks. It is more likely to be the remainder of this summer until water temperatures
start cooling in mid-August.
6. What about Recreation Summer Camps? Swimming at our beaches will not be allowed for our
summer camps. Alternative water activities are in the planning stages.
7. I bought a season beach parking pass. Am I able to get a partial refund? Patriots Park and
Lisicke Beach will still be open for other activities, including sunbathing on the beaches. The
refund issue is being referred to the Parks and Recreation Commission for input. We do not yet
have an answer on this issue.
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8. Is this related to the geese activity and closures for that? No, Patriots Park beach closures have
been related to geese activity, and lack of rain to move the water through the swim area. That
issue is being looked at independently, but is not related to the Blue Green Algae issue.
9. Are there fines for swimming in the water? This is a severe health issue. There is an absolute
prohibition at Town beaches, and possible associated fines for infractions at those locations. We
do not regulate other points of entry or Association beaches, but the health risk is very serious,
so we do not recommend going against these recommendations.
10. What do we need to watch for? The next stage in this algae bloom will be that as it dies off, it
becomes a floating scum. This is the most toxic exposure. Watch for a “scum” reporting system
in announcements for next week.
11. Where can I ask additional questions or get additional information?
• For health-related issues, contact EHHD at 860-429-3325 during working hours.
Website: http://www.ehhd.org/.
• For Coventry recreation questions, call 860-742-4068, Monday-Wednesday 8:30 AM –
4:30 PM, Thursday 8:30 AM – 6:30 PM, Friday 8:30 AM – 1:30 PM.
• See this link on the CT DEEP website for more details about Blue Green Algae.