East Canyon Reservoir Algal Bloom Monitoring 2019

Report a Bloom

24-Hour DEQ Environment Incidents Line: (801) 536-4123

Call Utah Poison Control Center

If you believe you or your pet have been exposed to a harmful algal bloom, call (800) 222-1222.

Visit the 2019 Photo Gallery

Update November 19, 2019

Toxin test results received from the Utah Public Health Lab (UPHL) for samples collected on November 12, 2019, at Taylor Hollow at East Canyon Reservoir showed anatoxin-a levels that exceeded the recreation health-based threshold for a Warning Advisory. Microcystin levels were well below the advisory threshold.

A Warning Advisory indicates a moderate relative probability of acute health risk, cell-count density of 20,000 – 10 million cells per milliliter (cells/ml), microcystin levels of 4-2,000 micrograms per liter (µg/L), or anatoxin-a levels above non-detect.

The Danger Advisory for Taylor Hollow has been removed. East Canyon, however, remains under a Warning Advisory.

Data Summary

Taylor Hollow

• Sample date: November 12, 2019
• Sample type: Surface sample
• Microcystin: <2.0 micrograms per liter (µg/L)
• Anatoxin-a: 0.35 µg/L

Taylor Hollow

• Sample date: November 12, 2019
• Sample type: Elbow-depth integrated composite sample
• Microcystin: <2.0 micrograms per liter (µg/L)
• Anatoxin-a: 0.12 µg/L

Update October 31, 2019

Toxin test results received from the Utah Public Health Lab (UPHL) for samples collected on October 22, 2019, at the Boat Ramp at East Canyon Reservoir showed anatoxin-a and microcystin levels well below the recreation health-based threshold for a Warning Advisory. Cyanobacteria cell-count concentration results are pending from PhycoTech.

A Danger Advisory indicates a high relative probability of acute health risk, cell-count density of >10 million cells per milliliter (cells/mL), microcystin levels >2,000 micrograms per liter (µg/L), or anatoxin-a levels >90 µg/L. A Warning Advisory indicates a moderate relative probability of acute health risk, cell-count density of 20,000 – 10 million cells per milliliter (cells/ml), microcystin levels of 4-2,000 micrograms per liter (µg/L), or anatoxin-a levels above non-detect.

Taylor Hollow remains closed and the rest of East Canyon remains under a Warning Advisory.

Data Summary

Boat Ramp

• Sample date: October 22, 2019
• Sample type: Elbow-depth integrated composite sample
• Microcystin: <0.10 micrograms per liter (µg/L)
• Anatoxin-a: <0.10 µg/L

Update October 18, 2019

The Weber-Morgan Health Department (WMHD) closed Taylor Hollow and issued a lakewide Warning Advisory for East Canyon Reservoir on October 18, 2019, after cyanobacteria cell-count concentration results from samples collected by the Division of Water Quality (DWQ) on October 16, 2019, at Taylor Hollow were almost eight times greater than the recreation health-based threshold for a Danger Advisory and visual observation indicated a lake-wide bloom. WMHD is posting closure signs at Taylor Hollow and Warning Advisory signs at access points on the reservoir.

The primary taxon in the surface sample was Dolichospermum, a known producer of potent cyanotoxins such as microcystin and anatoxin-a. The primary taxon in the water-column sample was Apahnizomenon, which can produce microcystin.

A Danger Advisory indicates a high relative probability of acute health risk, cell-count density of >10 million cells per milliliter (cells/mL), microcystin levels >2,000 micrograms per liter (µg/L), or anatoxin-a levels >90 µg/L. A Warning Advisory indicates a moderate relative probability of acute health risk, cell-count density of 20,000 – 10 million cells per milliliter (cells/ml), microcystin levels of 4-2,000 micrograms per liter (µg/L), or anatoxin-a levels above non-detect.

Data Summary

Taylor Hollow

• Sample type: Surface sample
• Sample date: October 16, 2019
• Cyanobacteria cell counts: 78,467,051 cells per milliliter (cells/mL)

Taylor Hollow

• Sample type: Elbow-depth integrated composite sample
• Sample date: October 16, 2019
• Cyanobacteria cell counts: 150,877 cells per milliliter (cells/mL)

Update October 15, 2019

Toxin test results for samples collected by the Division of Water Quality (DWQ) on October 2, 2019, at Taylor Hollow at East Canyon Reservoir exceeded the recreation health-based advisory threshold for a Warning Advisory for anatoxin-a. Microcystin levels were well below the advisory threshold. Cyanobacteria cell-count concentrations are pending from PhycoTech.

The DWQ monitoring crew observed cyanobacteria that resembled light green grass clippings and cylindrical nodules. There were isolated clumps in the water column. Overall, the bloom looked worse than the last visit.

A Warning Advisory indicates a moderate relative probability of acute health risk, cell-count density of 20,000 – 10 million cells per milliliter (cells/ml), microcystin levels of 4-2,000 micrograms per liter (µg/L), or anatoxin-a levels above non-detect.

The Warning Advisory remains in place for Taylor Hollow in East Canyon Reservoir.

Data Summary

• Sample type: Elbow-depth integrated composite sample
• Sample date: October 2, 2019
• Microcystin: <2.0 micrograms per liter (µg/L)
• Anatoxin-a: 0.133 µg/L
• Cyanobacteria cell counts: Pending

Update September 25, 2019

Toxin test results for samples collected by the Division of Water Quality (DWQ) on September 16, 2019, at Taylor Hollow at East Canyon Reservoir were well below the recreation health-based advisory threshold for a Warning Advisory. Cyanobacteria cell-count concentrations are pending from Phycotech.

The DWQ monitoring crew observed small visible cyanobacteria particulates in the water column that resembled grass clippings. The crew reported that conditions were much improved from last week’s visit.

A Warning Advisory indicates a moderate relative probability of acute health risk, cell-count density of 20,000 – 10 million cells per milliliter (cells/ml), microcystin levels of 4-2,000 micrograms per liter (µg/L), or anatoxin-a levels above non-detect.

The Warning Advisory remains in place for Taylor Hollow in East Canyon Reservoir.

Data Summary

• Sample type: Elbow-depth integrated composite sample
• Sample date: September 16, 2019
• Microcystin: <0.10 micrograms per liter (µg/L)
• Anatoxin-a: <0.10 µg/L

Update September 17, 2019

The Weber-Morgan Health Department (WMHD) issued a Warning Advisory for Taylor Hollow at East Canyon Reservoir on September 17, 2019, after toxin test results received from the Utah Public Health Lab (UPHL) for samples collected at Taylor Hollow by the Division of Water Quality (DWQ) on September 12, 2019, showed anatoxin-a levels exceeding the recreation health-based threshold for a Warning Advisory. Microcystin data were unavailable and cyanobacteria cell counts were below the advisory threshold. Dolichospermum, a known toxin producer, was the primary taxon in the samples.

East Canyon Reservoir remains open for recreation at this time. Recreationists are advised to not swim or waterski in areas of scum, avoid boating in areas of scum, keep animals away, and not ingest water. Visitors can still recreate in the reservoir but are cautioned to be mindful of water conditions, as blooms may move or disperse depending on temperature, wind, and weather.

The DWQ monitoring crew observed isolated clumps of cyanobacteria on the surface and cyanobacteria resembling grass clippings in the water column. DWQ will conduct follow-up sampling this week at additional sites on the reservoir.

A Warning Advisory indicates a moderate relative probability of acute health risk, cell-count density of 20,000 – 10 million cells per milliliter (cells/ml), microcystin levels of 4-2,000 micrograms per liter (µg/L), or anatoxin-a levels above non-detect.

Data Summary

• Sample type: Elbow-depth integrated composite sample
• Sample date: September 11, 2019
• Microcystin: Data unavailable
• Anatoxin-a: 0.12 micrograms per liter (µg/L)
• Cyanobacteria cell counts: 5,238 cells per milliliter (cells/mL)