Is the lake safe?

Butler County, Kansas

Butler County State Fishing Lake algae bloom status

Public health warning

KDHE advisory in effect, updated 16 October 2026

Is Butler County State Fishing Lake safe to swim in?

Kansas has a public health warning in effect for Butler County State Fishing Lake, last updated on 16 October 2026. The latest published sample, on 12 October 2026, was at Watch level (microcystin 7.5 µg/L, 116,214 cyanobacteria cells/mL). Blooms have been reported here in two separate years since 2025.

Avoid contact with green, scummy or discoloured water and keep dogs out of it.

Check today on the KDHE algae bloom map
Years with blooms
2 of 2
Usual months
Aug and Oct
Samples at Warning level or higher
1 of 6
Data checked
24 October 2026
See it on the Kansas map

Butler County State Fishing Lake algae bloom history

The Kansas Department of Health and Environment has tested Butler County State Fishing Lake 6 times since 2025, usually after someone reported a possible bloom. 3 samples (50%) reached at least Watch level, and 1 reached Warning level or higher.

The highest microcystin result was 10.27 µg/L, above KDHE's Warning threshold of 8 µg/L.

  1. 2025 4 samples, Watch
  2. 2026 2 samples, Warning
Warning levelWatch level

When do algae blooms happen at Butler County State Fishing Lake?

At Butler County State Fishing Lake, reports are most often logged in August and October.

Reports are spread across the year, with 33% between May and September.

Blooms can appear, move with the wind and fade within hours or days, so the time of year is only a guide.

January: 0% of reports
February: 0% of reports
March: 0% of reports
April: 0% of reports
May: 0% of reports
June: 0% of reports
July: 0% of reports
August: 33% of reports
September: 0% of reports
October: 67% of reports
November: 0% of reports
December: 0% of reports
Share of reports by month. Darker bars are the peak months.

Recent Butler County State Fishing Lake algae reports

DateLocationResult
12 October 2026 Not given Watch level · microcystin 7.5 µg/L, 116,214 cyanobacteria cells/mL
12 October 2026 Not given Warning level · microcystin 10.27 µg/L
8 September 2025 Not given Below advisory levels · microcystin 0.4 µg/L, 16,438 cyanobacteria cells/mL
8 September 2025 Not given Below advisory levels · microcystin 0.49 µg/L
25 August 2025 Not given Below advisory levels · microcystin not detected
25 August 2025 Not given Watch level · microcystin not detected, 239,814 cyanobacteria cells/mL

What the Kansas results mean

KDHE sets each advisory from lab results or what staff see at the lake. Samples on this page are labelled with the level their results reached.

Watch
A bloom is visible, microcystin is above 4 µg/L, or there are more than 80,000 cyanobacteria cells per mL. Avoid algae and keep people and pets from swimming near it or drinking the water.
Warning
Microcystin above 8 µg/L, more than 250,000 cells per mL, or heavy surface scum. Avoid all contact with the water, including fishing and boating.
Hazard
Microcystin above 2,000 µg/L or more than 10 million cells per mL. KDHE recommends closing all or part of the lake and sometimes the shore nearby.

Is Butler County State Fishing Lake safe for dogs?

Dogs are at the greatest risk from toxic algae. They swallow water while swimming, eat scum on the shore and lick algae off their fur afterwards, and a small amount can kill a dog within hours.

  • Keep your dog on a lead near water that looks green, scummy, foamy or discoloured, and away from algae washed up on the shore.
  • If your dog gets in, rinse it straight away with clean water and don't let it lick its coat.
  • Call a vet immediately if your dog vomits, drools, has diarrhoea, staggers, shakes or seems weak after being near the water.

Read the full guide to toxic algae and dogs: symptoms, what to do in the first minutes and how vets treat it.

Health effects of toxic algae

Blue-green algae (cyanobacteria) can produce toxins that affect the liver, nervous system and skin. Swallowing water during a bloom can cause stomach pain, vomiting and diarrhoea. Skin contact can cause rashes, and breathing spray from the water can irritate the eyes, nose and throat. Children are at higher risk because they are smaller and more likely to swallow water.

How to spot a bloom

Toxic blooms can look like pea soup, spilled paint or green streaks on the surface, and they can also be blue, brown, white or red. Scum often collects along the shore downwind. If you can't see your feet in knee-deep water, or you aren't sure, stay out.

Don't drink untreated lake water, and don't boil it to make it safe: boiling doesn't destroy algal toxins. If you feel unwell after contact with the water, contact a doctor or Poison Control on 1-800-222-1222.

Nearby lakes with algae reports

All Butler County lakes with algae reports

Questions about Butler County State Fishing Lake

Is there algae in Butler County State Fishing Lake right now?

Kansas has a public health warning in effect for Butler County State Fishing Lake, last updated on 16 October 2026. The latest published sample, on 12 October 2026, was at Watch level (microcystin 7.5 µg/L, 116,214 cyanobacteria cells/mL). This site checks KDHE's advisory list every day, but lakes are only sampled after a bloom is reported, so for today's conditions check the KDHE algae bloom map and the signs at the shore.

When was the last algae bloom at Butler County State Fishing Lake?

The most recent entry in Kansas's data is from 12 October 2026: a sample at Watch level (microcystin 7.5 µg/L, 116,214 cyanobacteria cells/mL).

Has Butler County State Fishing Lake had toxic algae before?

Yes. Blooms are recorded every year from 2025 to 2026, most often in August and October.

Can dogs swim in Butler County State Fishing Lake?

Keep dogs out of the water whenever a bloom is reported or the water looks green, scummy or discoloured. Dogs are the animals most often killed by algal toxins because they swallow water and lick their fur. If your dog swims in water that might have algae, rinse it with clean water and call a vet if it vomits, drools, staggers or seems weak.

Can you eat fish caught in Butler County State Fishing Lake during a bloom?

If you keep fish caught during a bloom, health agencies advise removing the guts and liver and rinsing the fillets in clean water before cooking, because toxins collect most in the organs. Some agencies advise not eating fish from an active bloom at all, so follow local guidance.

About this data

This page uses official records from the Kansas Department of Health and Environment (KDHE), which updated as samples come in, with advisories reviewed through the April to October season. Reports are grouped by waterbody. The site was last rebuilt on 24 October 2026.

States only test some lakes, some of the time, so a lake without a recent report hasn't necessarily been checked. This page is independent, isn't affiliated with the State of Kansas, and isn't health advice. View the source data.