Mid-August on Seneca Lake: Your Latest Update

It started off hot—really hot—earlier this week, but a steady breeze kept things comfortable and helped keep HABs at bay. This morning’s cooler air was a reminder that fall is just around the corner. Remember, lake conditions can shift quickly, so always “look before you leap.”

Each week, we bring together data from the Finger Lakes Institute, Pure Waters volunteers, and NOAA to give you a snapshot of what’s happening on (and in) the water.

Snapped a great photo on or around Seneca Lake this summer? We’d love to feature it. Send your pictures to info@senecalake.org.

Current Lake Conditions (Week of August 8–14)

Data from Finger Lakes Institute, Pure Waters Volunteers & NOAA

• HABs (Harmful Algal Blooms): 1
• Surface Water Temperature: 77°F at 1.3m depth
• Turbidity: 0.526 NTU (good if < 1)
• Dissolved Oxygen: 106% saturation
• Lake Level: 445.56 ft ASL

What is Turbidity?

Turbidity is a measure of how clear or cloudy the water is. It’s caused by tiny particles—like silt, algae, or organic matter—suspended in the water that scatter light, making it look murky. Lower turbidity means clearer water, which generally indicates better conditions for aquatic life and safer drinking water sources. In lakes like Seneca, turbidity below 1 NTU is considered good, showing that the water is relatively free of excess particles.

Pictured: Andrew and Nate Schmid enjoying Seneca Lake from Baskin Point in Starkey, NY.

HWA Treatment Update

Pure Waters recently treated 30 hemlock trees in Hector, NY, to defend them against the destructive Hemlock Woolly Adelgid. Using a safe, targeted spray at the base of each tree, we combined fast-acting and long-lasting protection—keeping chemicals out of nearby waterways. This work, paired with Cornell’s release of natural predators, gives our local hemlocks a fighting chance for the future. Read more!

2025 New York Invasive Species Expo

For those interested in invasive species research and management — registration is now open (and free!) for the 2025 New York Invasive Species Expo, Sept. 14–16 at Saratoga Spa State Park. This event will feature hands-on workshops, field trips, and presentations! Learn More & Register.

Mark Your Calendar: Hazardous Waste Day

Yates County’s Household Hazardous Waste Day is happening Saturday, September 13, 2025, at the Yates County Fairgrounds. This free event lets you safely dispose of hazardous chemicals and electronics, protecting your family and the environment. Learn More & Register.

A Lifetime on Seneca Lake

For Mimi, Seneca Lake isn’t just a place—it’s a lifetime of memories, family traditions, and a passion for protecting what she loves. Read her story and see why she’s dedicated decades to keeping our lake healthy. Read more!

Register Today: Annual Meeting

Join us Thursday, September 11 at The Oasis @ Hazlitt 1852 Vineyards for the Seneca Lake Pure Waters Association Annual Meeting and Volunteer Recognition. Celebrate our dedicated volunteers, hear updates on lake protection efforts, and connect with others who care about the health of Seneca Lake.

Event Details:

• Social Hour: 5:00–6:00 PM
• Meeting & Volunteer Recognition: 6:00–7:30 PM
• Location: 5712 NY-414, Hector, NY 14841
• Admission: Free

Track HABs on Seneca Lake & Stay Safe This Summer

Warm weather is here — and so is HABs season. Staying informed and taking action when you see something suspicious are two of the best ways to help protect yourself, your family, your pets, and Seneca Lake.

What to Watch For

Harmful algal blooms (HABs) can appear when water conditions are warm and calm. Keep an eye out for signs like:

• Water that looks like pea soup, spilled paint, or surface scum
• Streaks of green paint-like swirls
• Colors that are often green or blue-green
• Blooms that often collect near shorelines and in quiet coves
• 
  

If You Spot a Suspicious Bloom

Act quickly to help protect public health:

• Avoid Contact: Keep yourself and pets out of the water.
• Take Photos: Get clear photos and note the exact location.
• Submit a Report: To NYS DEC: Use the online reporting form to share details and upload photos. To Pure Waters:
• If you are would like us to take a look: Email your observations and photos to senecahabs@senecalake.org. We will do our best to respond in a timely manor. 

What Happens Next

The DEC will review your submission. Confirmed blooms are added to the NYS DEC HABs Map. Blooms reported by our observers can be found at Seneca Lake HABs Map & Current Bloom Chart.

Tip: Conditions can change quickly — if in doubt, stay out!

Our friends at the Community Science Institute (CSI) have created these handy graphics below to help everyone quickly identify harmful algal blooms (HABs).

Our lake protecting projects and programs are funded by donations and memberships from supporters like you. If you care about Seneca Lake, please consider a donation to help us continue with our vital work to protect the water quality and health of Seneca Lake now and for years to come.

Report a Bloom senecahabs@senecalake.org