7/1/2025
Keatons Lake HAB Update and Response Summary:
As we approach the holiday weekend, we recognize that the news regarding the presence of Harmful Algal Bloom (HAB) conditions in Keatons Lake is deeply disappointing to the community. We want to take this opportunity to provide further context, detail our response efforts, and explain how we reached this point.
Lake of the Woods Association follows a Harmful Algal Bloom Response Protocol, which outlines monitoring and treatment procedures from June through September. As part of this protocol, regular algae identification testing is conducted to track concentrations of potentially toxigenic cyanobacteria (PTOX).
The response plan includes the following thresholds:
Treatment recommended when concentrations reach 20,000–50,000 cells/mL.
Lake closure triggered when concentrations exceed 50,000 cells/mL.
Below are the most recent testing results for Keatons Lake:
May 28, 2025 – 9,800 cells/mL
June 13, 2025 – 6,400 cells/mL
June 19, 2025 – 4,310 cells/mL
June 25, 2025 – 89,900 cells/mL
As indicated above in the testing results, we experienced a significant spike in PTOX levels between June 19 and June 25—leaping from the “green” category (below 10,000 cells/mL) to well into the “red” category (above 50,000 cells/mL), which requires immediate lake closure. Referencing the Water Quality Testing Parameters: Algal Blooms in the Response Protocol.
This sudden increase is likely the result of several consecutive weather events, including heavy rainfall (which introduces nutrient runoff into the lake) followed by a stretch of high temperatures—ideal conditions for algae to proliferate rapidly.
Although the June 19 sample showed relatively low PTOX levels, in anticipation of potential growth and the upcoming holiday, we proactively scheduled SOLitude Lake Management to perform a treatment on July 2, 2025, with a follow-up treatment 10–14 days later.
According to SOLitude, the HAB treatment product remains effective for approximately 48 hours, so scheduling too early would allow time for regrowth before the July 4th weekend.
Despite our proactive planning, the rapid rise in cell counts between testing dates surpassed our expectations and required immediate closure.
Next Steps and Reopening Protocol:
Per our HAB Response Plan, reopening Keatons Lake requires:
- Waiting at least 48 hours after treatment for product efficacy.
- Conducting post-treatment testing to confirm reduced PTOX levels.
- Conducting a second round of testing approximately one week later.
- Ensuring all sample results fall below closure and advisory thresholds.
Given this required sequence and timing, Keatons Lake will remain closed through the July 4th holiday weekend.
We understand this is disappointing for members, but we remain committed to prioritizing public health and safety in accordance with our established environmental protocols.
We will continue to keep the community informed as we monitor progress and await post-treatment results.
To follow our Beach and Lake Statuses which includes water testing results click HERE.
To Learn More about Harmful Algal Bloom (HAB) and FAQ about HAB explore the Virginia Department of Health (VDH) Swim Healthy, Virginia webpage Click HERE.
To Access the Keatons Lake Harmful Algal Bloom Response Protocol Click HERE
