Is Hume Lake safe? Toxic algae status

Fresno County, California. Harmful algal bloom (blue-green algae) reports from the California State Water Resources Control Board.

Data checked 24 October 2026. California data is updated daily.

6

bloom reports since 2026

1 of 1

years with a bloom reported (2026–2026)

4

advisories recommended: 4 Caution, 0 Warning, 0 Danger

Year by year

Each box shows bloom reports logged that year, coloured by the highest advisory recommended.

2026 6 reports
Caution advisory

Reports at Hume Lake are most often logged in July and October.

Recent reports

DateLocationResult
9 October 2026 Beach near lake access parking lot Bloom reported
22 July 2026 north Caution
22 July 2026 west Caution
22 July 2026 east Caution
17 July 2026 In the Hume Lake Ranger District on Sequoia National Forest Bloom reported
16 July 2026 Sequoia National Forest Caution

What the results mean

Caution

Algae may be present. Stay away from scum and discoloured water, and keep pets and livestock from drinking it.

Warning

Toxins at higher levels. No swimming, and keep pets and children well away from the water.

Danger

High toxin levels. Stay out of the water and off the shoreline.

Dogs and toxic algae

Dogs face the greatest risk because they swallow water and lick algae off their fur. If a bloom has been reported, keep dogs out of the water and away from scum on the shore. If your dog swims in water that might have algae, rinse it with clean water straight away and call a vet if it seems unwell.

Common questions

Is Hume Lake safe to swim in?

The most recent entry in California's published data is from 9 October 2026: bloom reported (Beach near lake access parking lot). For current conditions, check the California HABs Portal map and posted signs.

When does Hume Lake get algae blooms?

In the state's records, reports are most often logged in July and October. Blooms are most likely in warm, calm weather, but they can appear at other times of year.

Source: California State Water Resources Control Board, official data. This page is independent and not affiliated with the State of California.