Androscoggin Lake: Algal Bloom Response
Latest Updates
09/09/2023
2023 WATER QUALITY UPDATE: Conditions on Androscoggin Lake have now reached “lake-wide algal bloom” status, with the most recent Secchi Disk Transparency (water clarity) reading taken on 9/7 at just 1.5 meters. The state of Maine defines the threshold for a “lake-wide algal bloom” at 2 meters and a “harmful algal bloom” (or HAB) at 1 meter of water clarity.
The dominant type of algae causing this bloom is a species of cyanobacteria called Dolichospermum. This is the most common bloom-forming species in Maine lakes, and is the same type of cyanobacteria responsible for the blooms in 2021 and 2022. Under certain conditions, this type of cyanobacteria can release toxins that are harmful to animals and humans. The reasons cyanobacteria produce toxins is not well understood, and standard monitoring techniques cannot predict when a bloom has toxins in it. Please refer to this Maine DEP webpage for more information and follow these guidelines:
- Do not accidentally ingest or drink lake water during a bloom. Well-maintained domestic water treatment systems may make lake water safe to drink by removing bacteria and parasites, but they are not guaranteed to remove algal toxins.
- If you shower with lake water, keep showers brief because breathing toxins in shower mist could cause health issues.
- Do not swim, water ski, or boat in areas where algae are visible (e.g., pea soup, floating mats, scum layers, etc.), where water is discolored, or where musty odors are present.
- Rules of thumb: if you are standing in water chest deep (4-5 feet ) and you can’t see your toes because the water is so green, you should get out; if you are looking into water that is 4-5 feet deep and can’t see the bottom of the lake because the water is so green, you should not to go in.
- Because algal scums along the shoreline have the highest concentrations of toxins, do not let children play in water that is discolored, where you see mats of algal material, foam, or where musty odors are present. Do not allow pets or livestock to swim or drink water from these areas.
- Rinse off with fresh water and soap if available, as soon as practical if exposed to water that has dense algae present. This will reduce skin exposure for humans and pets.
Please be aware that bloom conditions on your shoreline and throughout the open waters of the lake can change from day to day (or even by the hour) depending on the wind. If water clarity declines below 1 meter at our regular monitoring location, then we do not recommend swimming in any areas of the lake. For the most recent Secchi disk readings, please visit our website: https://30mileriver.org/androscoggin-lake/.
09/01/2023
2023 WATER QUALITY ANNOUNCEMENT:
Androscoggin Lake’s water clarity (Secchi disk transparency) has now declined to “near-bloom” conditions (secchi depth between 2-3 meters) with a current reading of 2.73 meters. A “lake-wide bloom”, as defined by Maine DEP, is when Secchi depth declines below 2 meters. Please be aware that algae can accumulate on down-wind shorelines during these conditions. Areas were algae has concentrated, forming scums, should be avoided by humans, pets, and livestock.
WHAT YOU NEED TO KNOW:
- The algal blooms in 2021, 2022, now 2023 consisted of cyanobacteria (formerly called blue-green algae)
- Some species of cyanobacteria can produce toxins under certain conditions
- Not all cyanobacteria blooms are toxic
- Areas where the algae have concentrated, forming scums, should be avoided by humans, pets, and livestock
- Avoid swallowing lake water while swimming, and do not allow pets or livestock to drink lake water
- Avoid using lake water for household uses, cooking, or drinking
- Shower and wash swimsuits after swimming
For more information about algae blooms and cyanobacteria, see below, and please visit Maine DEP’s informational webpages via the following links:
- https://www.maine.gov/dep/water/lakes/algalbloom.html
- https://www.maine.gov/dep/water/lakes/cyanobacteria.html
STAY INFORMED AND VIEW THE MOST RECENT DATA: https://30mileriver.org/androscoggin-lake/
08/17/2023
FUNDED! Androscoggin Lake Watershed Protection Project, Phase I (319 grant)
This much-needed project brings $149,730 of grant funding to the Androscoggin Lake watershed over the next two years! The grant will largely support construction costs associated with improvements to town roads, private roads, public and private property. All in effort to reduce erosion and phosphorus loading to the lake in order reduce the frequency of future algal blooms.
04/14/2023
Androscoggin Lake Watershed-Based Protection Plan (WBPP) Accepted by US EPA/ME DEP
Using information collected during the watershed survey, 30 Mile developed a Watershed-Based Protection Plan for Androscoggin Lake during the winter of ’22-’23. With assistance from ALIC, Maine DEP, and US EPA, the plan lays out a strategy for watershed mitigation and water quality protection efforts over the next 10 years. This also means we are now eligible to apply for federal Clean Water Act funding for the next 10 years that can support high-priority erosion mitigation projects identified during the watershed survey. Read the Androscoggin Lake WBPP HERE.
03/30/2023
Androscoggin Lake Watershed Survey & Report Complete! For more information and to read the report, visit 30 Mile’s watershed survey page.
30 Mile will update this webpage as information becomes available-
please check back for more updates!
Background
Androscoggin Lake experienced a severe cyanobacteria bloom in the summer of 2021. Near-bloom conditions were documented in 2022 and again in 2023. Maine Department of Environmental Protection (Maine DEP) defines a “lake-wide algal bloom” when water clarity <2 meters (~6 feet) depth at the deepest point in the lake (monitoring station #1).
What you need to know:
- The blooms in Androscoggin Lake consisted of cyanobacteria (formerly called blue-green algae)
- Some species of cyanobacteria can produce toxins under certain conditions
- Not all cyanobacteria blooms are toxic
- Areas where the algae have concentrated, forming dense scums or accumulations, should be avoided by humans, pets, and livestock
- Avoid swallowing lake water while swimming, and do not allow pets or livestock to drink lake water
- Avoid using lake water for household uses, cooking, or drinking
- Shower and wash swimsuits after swimming
For more information about algae blooms and cyanobacteria, please visit Maine DEP’s informational webpages via the following links:
Algal Bloom Information
What are cyanobacteria?
Cyanobacteria are a type of algae. Formerly called blue-green algae, cyanobacteria are aquatic bacteria that are able to photosynthesize. Originally called blue-green algae because dense blooms will turn the water green, or blue-green in color, cyanobacteria are a natural and important part of the lake ecosystem, and can be found in all lakes all over the world. However, when nutrient (phosphorus) concentrations are high enough and conditions are just right, their population can explode. The result is what we call a “cyanobacteria bloom” or “algal bloom.”
What kind of cyanobacteria is it?
The species of cyanobacteria have been identified as Dolichospermum (formerly known as Anabaena), a common bloom-forming species in Maine lakes. Microscope photos (right, courtesy of R. Windecker) show the filamentous algae consisting of multiple bead-like cells of three distinct cell types. Dolichospermum can produce toxins under certain environmental conditions.
Is the water toxic?
We do know that the species causing this bloom has the ability to produce toxin. We are collecting water samples for toxin analysis by US EPA, however test results are not immediate.
Maine DEP has been testing for cyanotoxins in Maine lakes for decades. Of all the toxin samples Maine DEP has collected, there were only a few open-water samples that exceeded EPA’s Drinking Water standard for the algal toxin microcystin for infants and non-school-age children. None of the samples exceeded the standard for school-age children or adults. No open water samples have exceeded EPA’s Recreational Standard – even when collected from lakes with blooms that are chronic and severe.
However, Maine DEP has detected very high concentrations of the algal toxin microcystin in down-wind algal scums that can accumulate along shorelines. This is why we advise everyone to stay away from any concentrated scums or accumulations near shorelines or in down-wind coves. Do not inadvertently drink the water in these areas, and do not let small children, pets, or livestock play in these areas or drink from the lake. Shower after swimming, and do not use lake water for household uses like cooking or drinking.
Out of an abundance of caution: When in Doubt -Stay Out!
What caused the bloom?
Cyanobacteria rely on three things: light, temperature, and nutrients. When it rains, phosphorus enters the lake via stormwater runoff that is delivered from the land in the watershed surrounding the lake. Phosphorus is a naturally occurring element found in soil, fertilizers, pet and livestock waste, and septic systems among other sources. It is found in very small amounts in the lake water, but is found in very large amounts on land in the watershed surrounding the lake. Every time it rains, water flows over the land and flows downhill – into the ditches, streams, and Androscoggin Lake. When too much phosphorus enters the lake, excess algae growth occurs.
Another important source of phosphorus are the sediments at the lake bottom. In the summer months, low oxygen levels in the deep waters of the lake can cause chemical reaction to occur at the sediment surface. This reaction causes the sediment to release phosphorus into the water column — a phenomenon known as “internal phosphorus loading”. To learn more, please read Androscoggin Lake’s 2022 Water Quality Report here: https://30mileriver.org/androscoggin-lake/
Image credit: UW Extension and Wisconsin DNR
What you can do RIGHT NOW to help:
- Participate in erosion control projects. If you are a landowner with an erosion site identified during the 2022 watershed survey, contact 30 Mile to see what cost-sharing opportunities are available to help implement your project!
- Host a Youth Conservation Conservation Corps (YCC) project on your property. Learn more at https://30mileriver.org/youth-conservation-corps/.
- Become LakeSmart! Contact ALIC’s LakeSmart team to receive a FREE evaluation, and learn more about how you can improve your property for the benefit of Androscoggin Lake. Request an evaluation by emailing lakesmart@androscogginlake.org, and visit https://www.lakes.me/lakesmart to learn more about this fantastic program!
- Become a member of the Androscoggin Lake Improvement Corporation (ALIC) and support their work to improve and protect Androscoggin Lake: https://www.androscogginlake.org/join.htm
- Donate to 30 Mile to support our water quality monitoring program and our work to address this problem: https://30mileriver.org/ways-to-give/
- Reduce soil erosion on your property as much as possible- exposed soil delivers phosphorus to the lake each time it rains – Phosphorus feeds algae in the lake!
- Establish or improve the stand of vegetation on your shoreline. The bigger (wider) your shoreline buffer, the better it is for Androscoggin Lake.
- Stop using fertilizers on your lakefront properties
- Maintain a healthy septic system, and pump your septic tank regularly.
- Learn more by visiting Maine DEP’s website for Shorefront Property Owners: https://www.maine.gov/dep/land/watershed/camp/index.html
Near-Live Water Quality Data & Annual Monitoring Reports
30 Mile continues to monitor Androscoggin Lake into November to document improved conditions in the lake. Over the winter months, we will analyze the data and compile our findings into an annual water quality monitoring report, which will be available via our website once complete.
In the meantime, be sure to check out the Secchi disk and dissolved oxygen data collected throughout this year’s monitoring season by visiting 30 Mile’s water quality webpage for Androscoggin Lake: https://30mileriver.org/androscoggin-lake/.