In 2025, CSI—working with Seneca County Health Department, Cayuga County Health Department, and Tompkins County Whole Health—adopted a strategic, risk-based sampling framework focused on fourteen high-use and high-exposure priority sites around the lake. Volunteers conduct weekly shoreline surveys and deliver samples to CSI’s certified laboratory, producing rapid, public-facing results shared through CSI’s Interactive HABs Map and Water Quality Database. This collaborative, community-powered approach offers an effective, scalable model for science-based HAB monitoring across the Finger Lakes.
Since 2018, Community Science Institute has led a volunteer-driven, community-powered harmful algal bloom monitoring program around Cayuga Lake that blends rigorous science, open data, and strong local partnerships to ensure timely and accurate HAB reporting. Through consistent shoreline monitoring, CSI has built a long-term dataset that supports public health decision-making and informs potential lake management strategies. By uniting trained volunteer community scientists with certified laboratory analysis and close collaboration with county health departments, local nonprofit partners, and state agencies, the program demonstrates how sustained, community-driven science can generate reliable data, fill critical information gaps, and guide evidence-based action.
If you observe a harmful a HAB on Cayuga Lake and are not one of CSI’s trained volunteers, you can submit a report using the 2026 Cayuga Lake Community HABs Report Form (the form will go live in spring/summer 2026).
Because HABs can form and dissipate rapidly, we encourage you to take several photos and submit your report the same day the bloom is observed, whenever possible. If you’d have additional questions or concerns, please send an email to HABsHotline@gmail.com.
In an effort to increase community participation and Cayuga Lakes shoreline monitoring coverage as the program continues to grow, we recruit new volunteers on an annual basis. The monitoring season will begin in June, and you’ll be contacted in May to attend an annual volunteer orientation session. Please fill this brief form out to get started!
HABs are caused by highly specialized, competitive, and ancient microscopic bacteria. These organisms are difficult to predict, challenging to remove once established, and some can produce toxins that pose risks to human, animal, and environmental health.
HABs can appear in several physical forms, including:
A simple “rake test” can help distinguish HABs from submerged aquatic plants—HABs often break apart or pass through the rake rather than coming up as intact plants.
This program would not be possible without the dedication and collaboration of our volunteers, community members, and partners—Cayuga Lake Watershed Network, Discover Cayuga Lake, Nicholas Leonard Dronography, Cayuga County Health Department, Seneca County Health Department, Tompkins County Whole Health, and the New York State Office of Parks, Recreation and Historic Preservation—whose support made the 2025 season possible. Through your collective vigilance and commitment, we are learning not only when blooms occur, but how they behave—and how, together, we can continue to better understand and protect Cayuga Lake.
For more information about the 2025 season, please read the article “Reports vs. Reality: Refining How We Read Cayuga Lake’s Harmful Algal Blooms“ which is included in CSI’s 2025 Water Bulletin Newsletter.
The CSI lab is equipped to perform three analyses on suspicious blooms: microscopy, total chlorophyll a, and microcystin. If initial inspection under the microscope confirms the presence of cyanobacteria, then chlorophyll a and microcystin analyses are performed.
