Be Lake Friendly!

  • Home

Recent News

Upcoming Events

Register now for the Harmful Algal Bloom forum on October 23, 2019 at Hobart and William Smith Colleges in Geneva NY. 

Bloom Map

Seneca Lake Bloom Data Spreadsheet

This link provides access to a spreadsheet containing detailed information about bloom samples obtained from Seneca Lake. Lab results will be updated as they become available.  Click here for a current scorecard.  The data table, scorecard and our interactive map will provide you with the latest and most current information.

Seneca Lake Interactive HABs Map Tips!
  • Recent reported blooms are light yellow dots. Older reports get darker until turning blue after one week. 

  • Clicking on a dot will bring up a window with data associated with the reported bloom as well as links to any photos.  
<< First  < Prev   1   2   Next >  Last >> 
  • 10/10/2019 7:55 PM | Anonymous member (Administrator)

    Observation Dates: September 30 - October 6, 2019

    Welcome to the bonus edition of Bloom Watch. The Epilogue.

    Just when we think we have a handle on how the cyanobacteria behave on Seneca Lake, we get surprised.

    Kudos to our volunteers! This week our volunteers continued to be alert and it paid off by finding very (to me) unexpected blooms. Although blooms can theoretically happen at any time, we have not seen them this late on Seneca Lake during the existence of our program (5 years). Of course, before this year, we were not looking that hard.


  • 10/01/2019 9:00 AM | Anonymous member (Administrator)

    Observation Dates: September 23 - 29, 2019

     % Zones Monitored: 72%  
     Suspicious Blooms:  1
     Confirmed Blooms:  1


  • 09/24/2019 9:00 AM | Anonymous member (Administrator)

    Observation Dates: September 16 - 23, 2019

     % Zones Monitored: 72%  
     Suspicious Blooms:  21
     Confirmed Blooms:  20


  • 09/17/2019 9:00 AM | Anonymous member (Administrator)

    Observation Dates: September 9 - 15, 2019

     % Zones Monitored: 50%  
     Suspicious Blooms:  7  
     Confirmed Blooms:  3


  • 09/10/2019 9:00 AM | Anonymous member (Administrator)

    Observation Dates: September 2 - 8, 2019

     % Zones Monitored: 87%  
     Suspicious Blooms:  46  
     Confirmed Blooms:  37


  • 09/06/2019 9:00 AM | Anonymous member (Administrator)

    Yesterday, a large number of blooms were identified on Seneca Lake.  The Finger Lakes Institute (FLI) at Hobart and William Smith Colleges tested six of a total of 16 bloom samples taken from Seneca Lake on Thursday September 5, 2019.  The lab reports that all six samples were above the threshold of 25 micrograms per liter of blue-green chlorophyll. Additional bloom samples are being processed today. This emphasizes the need for taking extreme caution when recreating on the lake.  Take special caution with small children and pets.

  • 09/03/2019 9:00 AM | Anonymous member (Administrator)

    Observation Dates: August 26-September 1, 2019

     % Zones Monitored: 73%  
     Suspicious Blooms:  0  
     Confirmed Blooms:  0


  • 08/26/2019 9:47 PM | Anonymous member (Administrator)

    Observation Dates: August 19-25, 2019

     % Zones Monitored: 80%  
     Suspicious Blooms:  3  
     Confirmed Blooms:  2 


  • 08/23/2019 9:00 AM | Anonymous member (Administrator)

    On August 21st, three water samples were collected on the west side of Seneca Lake between Kashong Point and Dresden. Two of the samples have been confirmed as Harmful Algal Blooms (HABs) by the Finger Lakes Institute lab.  A third sample was very close to being a bloom. 

  • 08/20/2019 9:00 AM | Anonymous member (Administrator)

    Observation Dates: August 12-18, 2019

     % Zones Monitored: 85%  
     Suspicious Blooms:  0  
     Confirmed Blooms:  0 


<< First  < Prev   1   2   Next >  Last >> 

HAB FACTS: What you need to know!

Exposure to any cyanobacteria HABs can cause health effects in people and animals when water with blooms is touched, swallowed, or when airborne droplets are inhaled. This is true regardless of toxin levels; some blue-green algae produce toxins, while others do not. Exposure to blooms and toxins can cause symptoms such as diarrhea, nausea or vomiting; skin, eye or throat irritation and allergic reactions or breathing difficulties.
Because blue-green algal bloom conditions change rapidly over time, the best prevention is to take steps to avoid waters with visible blooms: 

  • People, pets, and livestock should avoid areas with blooms or surface scums, or water that is noticeably discolored. 
  • Avoid blooms when swimming, boating, fishing, and don’t eat fish caught from areas of water with blooms.
  • If you or your pets are exposed to blue-green algal blooms, stop using the water and rinse off with clean water.
  • Consider medical attention for people and animals if symptoms such as diarrhea, nausea, or vomiting; skin, eye, or throat irritation; and allergic reactions or breathing difficulties occur after contact with surface waters with blooms.
  • Never drink untreated surface water. Even if you treat it in your home with water filtration, chlorine, ultraviolet (UV) light, or other treatment; it’s still not protected from blue-green algae and toxins.


Seneca Lake Pure Waters Association is working to protect and preserve the water quality of Seneca Lake.  This amazing natural resource provides abundant amounts of drinking water, recreation, fishing and economic opportunities for the greater Seneca Lake community as well as visitors to our region. Through decades of dedication and hard work, Seneca Lake Pure Waters Association has earned the respect of both local and state organizations responsible for water quality.  

Our organization has been instrumental in developing water quality monitoring programs for the Seneca Lake Watershed, including: 

  • Stream Monitoring We routinely collect water samples from the six main tributaries that supply over 60% of the water flowing into the lake.  The water samples are analyzed by the Community Science Institute (SCI), a NYS certified laboratory and the results are made available to the public.
  • Lake Monitoring: In partnership with the NYS DEC and NYS Federation of Lakes Associations, we evaluate multiple deep and shallow lake locations for key water quality indices throughout the year.

  • Shoreline Monitoring:  Working in partnership with the Finger Lakes Institute (FLI) and the NYS DEC, our 100+ team of volunteers monitor over 56 miles of shoreline to locate Cyanobacteria (Harmful Algal)  blooms, which can be a health threat for humans and animals. 

- Business Member Support -

Seneca Lake Pure Waters Association
PO Box 247
Geneva, NY 14456

2019 © Seneca Lake Pure Waters Association

Follow our activities

Powered by Wild Apricot Membership Software