Utah Lake Algal Bloom Monitoring 2020

Utah County Alerts

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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.

Update November 2, 2020

The Warning Advisories for Utah Lake have been removed as a result of the end of the sampling and monitoring recreation season.

The Utah Division of Water Quality’s water recreation season runs from May 1 through October 31. At this time, no further monitoring or sampling for harmful algal blooms or waterborne pathogens at priority water bodies will be conducted until May 2021.

This does not mean that the potential for harmful algal blooms or waterborne pathogens has ceased. Please remain aware while recreating in or near water bodies and for information on how to keep yourself, your family, and your pets safe, please visit:

• Protect Yourself During Harmful Algal Blooms
• Protect Yourself: Waterborne Pathogens

Update September 17, 2020

Utah County Health Department has issued a Danger Advisory for the State Park Marina. The marina remains open for boat traffic to access Utah Lake but water recreation within the marina should be avoided.

On September 10, 2020, the DWQ HABs monitoring team visited Utah Lake. The monitoring team observed a harmful algal bloom at Lincoln Marina, the State Park Marina, Provo Bay, American Fork Marina and the open water. Cyanotoxin and toxigenic cyanobacteria cell count densities samples were taken.

Results delivered from Phycotech on 09/16/2020 show the presence of high toxigenic cell count densities in some areas. At the State Park Marina, toxigenic cyanobacteria cell count densities were over 7 times the DWQ/DOH Recreational Health Threshold for a danger advisory of 10,000,000 cells/mL. Please see the table below for additional results across the lake.

Update September 3, 2020

On August 31, 2020, the DWQ HABs monitoring team visited Utah Lake. The monitoring team observed a harmful algal bloom at American Fork Marina, Lindon Marina, Lincoln Marina, and the open water. Cyanotoxin and toxigenic cyanobacteria cell count densities samples were taken. Results delivered from Phycotech on September 2, 2020, show the presence of high toxigenic cell count densities in some areas with Lindon Marina, American Fork Marina, and Lincoln Marina all above the DWQ/DOH Recreational Health Threshold for an advisory.

Please see the table below for additional results across the lake.

Update August 27, 2020

Utah County Health Department has issued a Danger Advisory for Lincoln Marina. The marina remains open for boat traffic to access Utah Lake but water recreation within the marina should be avoided.

On August 24, 2020, the DWQ HABs monitoring team visited Utah Lake. The monitoring team observed a harmful algal bloom at American Fork Marina, Lindon Marina, Lincoln Marina, and the open water. Cyanotoxin and toxigenic cyanobacteria cell count densities samples were taken.

Results delivered from Phycotech on August 27, 2020, show the presence of high toxigenic cell count densities in some areas. Cyanotoxin results are still pending from UDAF Lab.

At Lincoln Marina, toxigenic cyanobacteria cell count densities were nearly 5 times the DWQ/DOH Recreational Health Threshold for a danger advisory of 10,000,000 cells/mL. Please see the table below for additional results across the lake.

Sample Dates: August 7 & 10, 2020

Toxin levels shown in micrograms per liter (µg/L); toxigenic cell concentration cells/ml
(E) = enzyme-linked immunosorbent assay (ELISA);
(L)= liquid chromatography-mass spectrometry (LCMS)

Update August 19, 2020

Utah Lake was sampled on 8/7&10/2020. Notable results are from the Open Waters of Utah Lake. This bloom is quite distinct and heavily dominated by Planktothrix. The toxigenic cell concentration exceeds the recommended Warning advisory by a factor >7. The Utah County Health Department is issuing a Warning advisory for the open water of Utah Lake and posting signage at Utah Lake State Park.

American Fork marina is currently under a Warning advisory. However, recent toxigenic cell counts exceed the recommended Danger advisory by a factor of 14. The Utah County Health Department is issuing a Danger Advisory for American Fork marina. The marina remains open for boat traffic to access Utah Lake, but water recreation within the marina should be avoided.

Update August 14, 2020

• American Fork Marina August 7 toxin results: 48.1 ug/L microcystin (surface)
• Open Water August 10 toxin results
  • Outside Lindon marina: 0.44 ug/L microcystin (depth-integrated composite)
  • Provo WQ Buoy: 0.23 ug/L microcystin (depth-integrated composite)
  • Goshen Bay: 0.51 ug/L microcystin (depth-integrated composite)
• Lincoln Marina August 10 toxin results: 123 ug/L microcystin (surface)

Update July 31, 2020

Division of Water Quality (DWQ) monitoring crews collected samples at a variety of Utah Lake locations on July 14, 2020, and July 20, 2020. Toxin test results showed microcystin levels exceeding the recreational health-based thresholds in surface and water column samples at Lincoln Marina/Lincoln Beach and in surface samples at the beach inside Lindon Marina.

DWQ monitoring crews observed blooms throughout the lake and noted that the blooms increased in magnitude between July 14, 2020, and July 20, 2020. Blooms resembled grass clippings and spilled paint, with isolated clumps observed in the water column and the water surface.

DWQ is using two different toxin testing methods this season: enzyme-linked immunosorbent assay (ELISA) and liquid chromatography-mass spectrometry (LCMS). The tables below note the method used for each sample, denoted by (E) for ELISA and (L) for LCMS.

The Warning Advisory for Lincoln Marina, Lindon Marina, and American Fork Marina remains in place.

A Warning Advisory indicates a moderate relative probability of acute health risk, toxigenic cyanobacteria cell densities between 100,000 and 10,000,000 cells per milliliter (cells/mL), microcystin levels between 8 and 2,000 micrograms per liter (µg/L), cylindrospermopsin levels greater than 15µg/L, or anatoxin-a levels from 15 µg/L to 90 µg/L.

Sample Date: July 20, 2020

Toxin levels shown in micrograms per liter (µg/L)

Sample Date: July 14, 2020

Toxin levels shown in micrograms per liter (µg/L)

Update July 19, 2020

The Utah County Health Department (UCHD) issued a Warning Advisory on July 19, 2020, for Lincoln Marina after toxin test results from samples collected by the Division of Water Quality (DWQ) on July 14, 2020, showed microcystin levels exceeding the recreational health-based threshold for a Warning Advisory. Microcystin concentrations were 193.0 micrograms per liter (µg/L). The advisory threshold is 8.0 µg/L.

The DWQ monitoring crew will return to Utah Lake today to conduct follow-up sampling.

A Warning Advisory indicates a moderate relative probability of acute health risk, toxigenic cyanobacteria cell densities between 100,000 and 10,000,000 cells per milliliter (cells/mL), microcystin levels between 8 and 2,000 micrograms per liter (µg/L), cylindrospermopsin levels greater than 15µg/L, or anatoxin-a levels from 15 µg/L to 90 µg/L.

• Sample date: July 14, 2020
• Sample type: Surface sample
• Microcystin: 193.0 micrograms per liter (µg/L)

Update July 10, 2020

The Utah County Health Department issued a Warning Advisory on July 10, 2020, for American Fork Marina and Lindon Marina after sample results collected by the Division of Water Quality (DWQ) in the open water between the two marinas on July 6, 2020, showed microcystin levels exceeding the recreational health-based threshold for a Warning Advisory.

The DWQ monitoring crew will return to Utah Lake next week to conduct a lakewide survey and collect follow-up samples in the area under the Warning Advisory.

A Warning Advisory indicates a moderate relative probability of acute health risk, toxigenic cyanobacteria cell densities between 100,000 and 10,000,000 cells per milliliter (cells/mL), microcystin levels between 8 and 2,000 micrograms per liter (µg/L), cylindrospermopsin levels greater than 15µg/L, or anatoxin-a levels from 15 µg/L to 90 µg/L.

• Sample date: July 6, 2020
• Sample type: Elbow-depth composite sample
• Microcystin: 25.4 micrograms per liter (µg/L)
• Anatoxin-a: <1.5 ug/L

Update July 9, 2020

Portions of Utah Lake are under a Health Watch after a Division of Water Quality (DWQ) monitoring team observed a water-column bloom in the open water between American Fork Marina and Lindon Marina on July 6, 2020. Another DWQ monitoring team observed a similar bloom at Sandy Beach on July 8, 2020. Samples were collected on both days, and results are pending.

A Health Watch is not a formal advisory level but rather an indicator that a bloom may exist or become more severe based on available information from the DEQ Division of Water Quality (DWQ) and Department of Health. Indicators can include visual reports. The Utah County Health Department and Utah State Parks have been notified.