Utah Lake Algal Bloom Monitoring 2018

Warning Advisory

  • Do not swim or water ski
  • Do not ingest the water
  • Keep pets and livestock away
  • Clean fish well and discard guts
  • Avoid areas of scum when boating

Utah County Alerts

To sign up for updates: go to alerts.utahcounty.gov and create an account. Select contact methods. Create profile, select location. Choose alert subscription “Utah Lake” under “Utah County Alerts.”

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.


Get BloomWatch App

Help us track cyanobacteria blooms with your smartphone. Go to cyanos.org for more info.

Update November 1, 2018

The Utah County Health Department (UCHD) has lifted the Danger Advisory for Lincoln Beach, downgrading the health-based recreational-use recommendation to a Warning Advisory. UCHD changed the signage at the marina today.

Recent toxin testing showed a significant decrease in anatoxin-a and microcystin levels at the Lincoln Marina. This decrease led to the health department’s decision to adjust the advisory level to better reflect current conditions.

The Division of Water Quality (DWQ) collected samples at seven locations on Utah Lake on October 22, 2018. Toxin test results were non-detect for anatoxin-a at all locations, with the exception of Lindon Marina (0.37 µg/L). Microcystin levels ranged from 770 micrograms per liter (µg/L) at Lindon Marina to non-detect at the Provo Bay Ski Dock.

Toxin levels at Lindon Marina and American Fork Harbor exceeded the recreation health-based threshold for a Warning Advisory. Cyanobacteria cell-count concentrations were well below the recreation health-based threshold at most sample sites with the exception of Lindon Marina and American Fork Harbor.

While the monitoring crew observed a green hue throughout the lake, only sparse, isolated green cyanobacteria clumps were seen at any site. Open water sites appeared predominantly free of cyanobacteria accumulation. American Fork Marina and Lindon Marina were the only sites that displayed any visible sign of cyanobacteria. Visually, Lindon Marina was comparable to American Fork Marina (i.e., isolated cyanobacteria green clumps). Lincoln Marina was much improved with no visible sign of a bloom. Overall, there seemed to be a downward trend of cyanobacteria presence at Lincoln Marina, and there was no visible cyanobacteria accumulation in the inlet to Lincoln Marina. Overall, cyanobacteria appeared to be less abundant and limited to certain areas of the lake.

The Warning Advisory for Utah Lake remains in effect.

Sample Location and Sample Type

  • Two miles west of Vineyard (surface sample)
  • One mile west of Provo Boat Harbor (surface sample)
  • One mile southeast of Bird Island (elbow-depth integrated composite sample)
  • Provo Bay Ski Dock (elbow-depth integrated composite sample)
  • Lindon Marina (surface sample)
  • Lincoln Marina (elbow-depth integrated composite sample)
  • American Fork Harbor (surface sample)

Toxin Test Results

Test results from the Utah Public Health Lab (UPHL) unless otherwise noted.

  • Two miles west of Vineyard: <0.10 micrograms per liter (µg/L) of anatoxin-a; 0.19 µg/L of microcystins
  • One mile west of Provo Boat Harbor: <0.10 µg/L of anatoxin-a; 0.21 µg/L of microcystins
  • One mile southeast of Bird Island: <0.10 µg/L of anatoxin-a; 0.21 µg/L of microcystins
  • Provo Bay Ski Dock: <0.10 µg/L of anatoxin-a; <0.10 µg/L of microcystins
  • Lindon Marina: 0.37 µg/L of anatoxin-a; 770 µg/L of microcystins (1000x dilution)
  • Lincoln Marina: <0.10 µg/L of anatoxin-a; 4.0 µg/L of microcystins (Utah Department of Agriculture and Food (UDAF) lab)
  • American Fork Harbor: <0.10 µg/L of anatoxin-a; 76 µg/L of microcystins (100x dilution)

Cyanobacteria Cell-Count Concentrations

  • Two miles west of Vineyard: 1,962 cells per milliliter (cells/ml)
  • One mile west of Provo Boat Harbor: 8,499 cells/ml
  • One mile southeast of Bird Island: 5,181 cells/ml
  • Provo Bay Ski Dock: 551 cells/ml
  • Lindon Marina: 196,105 cells/ml
  • Lincoln Marina: 9,764 cells/ml
  • American Fork Harbor: 70,160 cells/ml

Update October 29, 2018

The Division of Water Quality (DWQ) collected samples at nine locations on Utah Lake on October 16, 2018. Toxin test results for four sample sites exceeded the recreation health-based threshold for a Warning Advisory for anatoxin-a, and toxin results for Lindon Marina, 1 mile west of Provo Boat Harbor, Lincoln Marina, and the Lincoln Marina inlet exceeded the recreation health-based threshold for a Warning Advisory for microcystins. Cyanobacteria cell-count concentrations exceeded the recreation health-based threshold for a Warning Advisory at seven of the nine sample sites.

American Fork Marina and Lindon Marina displayed signs of very sparse, isolated green cyanobacteria clumps, but conditions had improved overall. Lincoln Marina showed signs of a bloom, which was surprising because the bloom was non-existent the previous week. The monitoring crew also observed fairly thick and abundant cyanobacteria accumulation in the inlet to Lincoln Marina. Bloom material–green clumps or surface dusting–was seen at all of the sites except Provo Bay Ski Dock. Bloom material resembling grass clippings was observed in isolated chunks floating near the surface. In some locations, there was also a green dusting visible on the surface. Overall, cyanobacteria appeared to be more abundant but isolated to particular areas of the lake.

The Warning and Danger Advisories at Utah Lake remain in effect.

Sample Locations and Sample Types

  • American Fork Harbor (surface sample)
  • Open water (surface sample)
  • Lindon Marina (surface sample)
  • Two miles west of Vineyard (surface sample)
  • One mile west of Provo Boat Harbor (surface sample)
  • Provo Bay Ski Dock (elbow-depth integrated composite sample)
  • One mile southeast of Bird Island (elbow-depth integrated composite sample)
  • Lincoln Marina (surface sample)
  • Inlet to Lincoln Marina (surface sample)

Toxin Test Results

Test results from the Utah Department of Agriculture and Food (UDAF) lab and Utah Public Health Lab (UPHL) as noted.

  • American Fork Harbor: 0.12 micrograms per liter (µg/L) of anatoxin-a (UDAF); 3.6 µg/L of microcystins (UPHL)
  • Open water: 0.22 µg/L of anatoxin-a (UPHL); 0.72 µg/L of microcystins (UPHL)
  • Lindon Marina: <0.10 µg/L of anatoxin-a (UPHL); >4 µg/L of microcystins (UPHL)
  • Two miles west of Vineyard: 0.15 of anatoxin-a (UPHL); 0.87 µg/L of microcystins (UDAF)
  • One mile west of Provo Boat Harbor: <0.10 µg/L of anatoxin-a (UPHL); 4.6 µg/L of microcystins (UPHL)
  • Provo Bay Ski Dock: 0.13 µg/L of anatoxin-a (UPHL); <0.10 of microcystins (UPHL)
  • One mile southeast of Bird Island: <0.10 of anatoxin-a (UPHL); 0.67 µg/L of microcystins (UPHL)
  • Lincoln Marina: <0.10 µg/L of anatoxin-a (UDAF); 90 µg/L of microcystins (100x dilution) (UDAF)
  • Inlet to Lincoln Marina: <0.10 µg/L of anatoxin-a (UDAF); 6.6 µg/L of microcystins (10x dilution) (UDAF)

Cyanobacteria Cell-Count Concentrations

  • American Fork Harbor: 2,171 cells per milliliter (cells/ml)
  • Open water: 276,889 cells/ml
  • Lindon Marina: 7,976 cells/ml
  • Two miles west of Vineyard: 34,155 cells/ml
  • One mile west of Provo Boat Harbor: 311,183 cells/ml
  • Provo Bay Ski Dock: 831 cells/ml
  • One mile southeast of Bird Island: 249,907 cells/ml
  • Lincoln Marina: 1,524,919 cells/ml
  • Inlet to Lincoln Marina: 6,068,341 cells/ml

Update October 25, 2018

American Fork Marina, October 10, 2018

The Division of Water Quality (DWQ) collected samples at seven sites on Utah Lake on October 10, 2018. Cyanobacteria cell-count concentrations were significantly lower than previous weeks, perhaps due to rain and wind that dissipated blooms and moved cyanobacteria to other parts of the lake. Despite the lower cyanobacteria cell counts, microcystin levels remained elevated at four of the seven sites. Anatoxin-a levels were non-detect at all but two of the sample sites.

The bloom was less abundant overall in comparison to the previous week. However, the water was still turbid, with a green hue. Bloom material was seen at Lindon Marina, American Fork Marina, two miles west of Vineyard, and one mile west of Provo Harbor. American Fork Marina had isolated chunks as well as a green dusting throughout the entire marina. The long-standing bloom in Lincoln Marina had dissipated, and there was no visible bloom in the marina. Overall, bloom conditions appeared less abundant throughout the whole lake.

Warning and Danger Advisories remain in effect for Utah Lake.

Sample Locations and Sample Types

  • Two miles west of Vineyard (surface sample)
  • One mile west of Provo Boat Harbor (surface sample)
  • One mile southeast of Bird Island (elbow-depth integrated composite sample)
  • Provo Bay Ski Dock (elbow-depth integrated composite sample)
  • Lindon Marina (surface sample)
  • Lincoln Marina (elbow-depth integrated composite sample)
  • American Fork Harbor (surface sample)

Toxin Test Results

Test results from the Utah Department Department of Agriculture and Food (UDAF) lab unless otherwise noted.

  • Two miles west of Vineyard: <0.10 micrograms per liter (µg/L) of anatoxin-a; 24 µg/L of microcystin (100x dilution)
  • One mile west of Provo Boat Harbor: <0.10 µg/L of anatoxin-a; 144 µg/L of microcystin (50x dilution)
  • One mile southeast of Bird Island: <0.10 µg/L of anatoxin-a; >5 µg/L of microcystin
  • Provo Bay Ski Dock: 0.12 µg/L of anatoxin-a (Utah Public Health Lab (UPHL); 0.12 µg/L of microcystin (UDAF)
  • Lindon Marina: 0.11 µg/L of anatoxin-a (UPHL); 380 µg/L of microcystin (1000x dilution) (UPHL)
  • Lincoln Marina: <0.10 µg/L of anatoxin-a; 2.3 µg/L of microcystin (UPHL)
  • American Fork Harbor: <0.10 µg/L of anatoxin-a; >5 µg/L of microcystin (UDAF)

Cyanobacteria Cell-Count Concentrations

  • Two miles west of Vineyard: 13,259 cells per milliliter (cells/ml)
  • One mile west of Provo Boat Harbor: 20,338 cells/ml
  • One mile southeast of Bird Island: 6,824 cells/ml
  • Provo Bay Ski Dock: 1,626 cells/ml
  • Lindon Marina: 48,201 cells/ml
  • Lincoln Marina: 27,032 cells/ml
  • American Fork Harbor: 10,140 cells/ml

Update October 24, 2018

Lindon Marina, October 3, 2018

The Division of Water Quality (DWQ) received updated toxin test results from samples collected at Utah Lake on October 3, 2018. Microcystin levels at American Fork Harbor and Lindon Marina exceeded the recreation health-based threshold for a Danger Advisory, with microcystin concentrations at Lindon Marina 20.5 times higher than the Danger threshold. Microcystin levels at five of the eight sample sites exceeded the recreation health-based threshold for a Warning Advisory.

Anatoxin-a levels at American Fork Boat Harbor, two miles west of Vineyard, and Lindon Marina also exceeded the recreation health-based threshold for a Warning Advisory. The Provo Bay Ski Dock was well below the advisory thresholds for anatoxin-a and microcystin.

Cyanobacteria cell-count densities were above the recreation health-based threshold for a Warning Advisory at four of the seven sites. Cell-counts were above the recreation health-based threshold for a Danger Advisory at American Fork Boat Harbor and Lindon Marina, with cell-count densities at Lindon Marina almost seven times higher than the Danger threshold.

Warning and Danger Advisories remain in effect for Utah Lake.

Toxin Test Results

Test results from the Utah Public Health Lab (UPHL)

  • American Fork Boat Harbor: 0.3 micrograms per liter (µg/L) of anatoxin-a; 3900 µg/L of microcystin (1000x dilution)
  • Two miles west of Vineyard: 0.12 µg/L of anatoxin-a; 300 µg/L of microcystin (100x dilution)
  • One mile west of Provo Boat Harbor: <0.10 µg/L of anatoxin-a; 79 µg/L of microcystin (100x dilution)
  • Provo Bay Ski Dock: <0.10 µg/L of anatoxin-a; 0.13 µg/L of microcystin
  • One mile southeast of Bird Island: <0.10 µg/L of anatoxin-a; 120 µg/L of microcystin (100x dilution)
  • Lindon Marina: 0.16 µg/L of anatoxin-a; 41,000 µg/L of microcystin (100,000x dilution)
  • Lincoln Marina: <0.10 µg/L of anatoxin-a; 28 µg/L of microcystin (10x dilution)
  • Open water: <0.10 µg/L of anatoxin-a; 880 µg/L of microcystin (1000x dilution)

Cyanobacteria Cell-Count Concentrations

  • American Fork Boat Harbor: 18,124,807 cells per milliliter (cells/ml)
  • Two miles west of Vineyard: 49,762 cells/ml
  • One mile west of Provo Boat Harbor: 435,019 cells/ml
  • Provo Bay Ski Dock: 1,147 cells/ml
  • One mile southeast of Bird Island: 145,330 cells/ml
  • Lindon Marina: 67,739,592 cells/ml
  • Lincoln Marina: 482,303 cells/ml
  • Open water: 115,385 cells/ml

Update October 12, 2018

The Division of Water Quality (DWQ) received cyanobacteria cell-count concentration results today for samples collected at eight locations on Utah Lake on October 3, 2018. Cyanobacteria cell-count densities at American Fork Boat Harbor (approximately 18 million cells per milliliter (cells/ml)) and Lindon Marina (approximately 68 million cells/ml) exceeded the recreation health-based threshold for a Danger Advisory. Cell counts at five of the six remaining sample sites exceeded the recreation health-based threshold for a Warning Advisory. Cyanobacteria cell counts at the Provo Bay Ski Dock were well below advisory levels.

Cyanobacteria Cell-Count Concentrations

  • American Fork Boat Harbor: 18,124,807 cells per milliliter (cells/ml)
  • Two miles west of Vineyard: 49,762 cells/ml
  • One mile west of Provo Boat Harbor: 435,019 cells/ml
  • Provo Bay Ski Dock: 1,147 cells/ml
  • One mile southeast of Bird Island: 145,330 cells/ml
  • Lindon Marina: 67,739,592 cells/ml
  • Lincoln Marina: 482,303 cells/ml
  • Open water: 115,385 cells/ml

Warning and Danger Advisories remain in effect at Utah Lake.


Update October 9, 2018

The Division of Water Quality (DWQ) collected eight samples on Utah Lake on October 3, 2018. Anatoxin-a levels in the sample at Lindon Marina exceeded the recreation health-based threshold for a Warning Advisory; all other samples for anatoxin-a were non-detect. Microcystin levels continued to be high, with seven of eight samples exceeding the recreation health-based threshold for a Warning Advisory. The only sample site to fall below the threshold for microcystin was the Provo Bay Ski Dock. Further dilutions by the lab will be necessary to quantify microcystin concentrations at the other seven sample sites. Preliminary values could go even higher after these dilutions.

Monitoring crews reported that cyanobacteria were more widespread in the lake compared with the previous week.

The following sites displayed signs of cyanobacteria accumulation:

  • American Fork Marina: Cyanobacteria curds abundant in isolated chunks. Green color persistent throughout the water column.
  • Lindon Marina: Green cyanobacteria floating on the surface of the water. Scum visible along the shoreline. Water darker green closer to the shore.
  • Lincoln Marina: Cyanobacteria forming a surface scum observed along the shoreline. Surface scum isolated along the beach, but green clumps of cyanobacteria were observed floating further out into the Marina.

The three open-water buoy sites also displayed cyanobacteria accumulation. Small clumps of green cyanobacteria were observed throughout the lake.

Sample Locations and Sample Types

  • American Fork Boat Harbor (surface sample)
  • Two miles west of Vineyard (surface sample)
  • One mile west of Provo Boat Harbor (surface sample)
  • Provo Bay Ski Dock (elbow-depth integrated composite sample)
  • One mile southeast of Bird Island (surface sample)
  • Lindon Marina (surface sample)
  • Lincoln Marina (surface sample)
  • Open water (surface sample)

Toxin Test Results

Test results from the Utah Department of Agriculture and Food (UDAF) lab.

  • American Fork Boat Harbor: <0.10 micrograms per liter (µg/L) of anatoxin-a; >500 µg/L of microcystin (100x dilution)
  • Two miles west of Vineyard: <0.10 µg/L of anatoxin-a; >50 µg/L of microcystin (10x dilution)
  • One mile west of Provo Boat Harbor: <0.10 µg/L of anatoxin-a; >50 µg/L of microcystin (10x dilution)
  • Provo Bay Ski Dock: <0.10 µg/L of anatoxin-a; 0.20 µg/L of microcystin
  • One mile southeast of Bird Island: <0.10 µg/L of anatoxin-a; 271 µg/L of microcystin (1000x dilution)
  • Lindon Marina: 0.21µg/L of anatoxin-a; >50 µg/L of microcystin (10x dilution)
  • Lincoln Marina: <0.10 µg/L of anatoxin-a; >5 µg/L of microcystin
  • Open water: <0.10 µg/L of anatoxin-a; >50 µg/L of microcystin (10x dilution)

Warning and Danger Advisories remain in effect at Utah Lake.


Update October 9, 2018

The Utah Department of Agriculture and Food (UDAF) lab conducted further testing on samples collected on Utah Lake on September 26, 2018, with microcystin levels >5 micrograms per liter (µg/L). Additional dilutions quantified the microcystin levels at sample sites near Vineyard and at Lincoln Marina, but further dilutions by the lab will be necessary to quantify microcystin concentrations at the other sample sites. Preliminary values could go even higher after these dilutions.

Toxin Test Results

  • American Fork Marina: >500 µg/L of microcystin (100x dilution)
  • Two miles west of Vineyard: 18.4 µg/L of microcystin (10x dilution)
  • One mile west of Provo Boat Harbor: >5 µg/L of microcystin
  • One mile southeast of Bird Island: >5 µg/L of microcystin
  • Lindon Marina: >50 µg/L of microcystin (10x dilution)
  • Lincoln Marina: 856 µg/L of microcystin (1000x dilution)
  • Open water: >50 µg/L of microcystin (10x dilution)

Warning and Danger Advisories remain in effect at Utah Lake.


Update October 4, 2018

The Division of Water Quality (DWQ) collected samples at eight monitoring sites (three marinas, four high-frequency buoy/sonde sites, and one open water site) on September 26, 2018. Toxin test results from the Utah Public Health Lab (UPHL) showed the presence of anatoxin-a at four of the eight sample sites and microcystin levels >5 micrograms per liter (µg/L) at all but one sample site (Provo Bay). These microcystin levels exceed the recreation health-based threshold for a Warning Advisory. Further dilutions by the lab will be necessary to quantify microcystin concentrations, and the preliminary values could go even higher after these dilutions. These test results indicate elevated microcystin levels throughout much of the lake.

Monitoring crews observed cyanobacteria blooms/accumulation at seven of the eight sample locations:

  • American Fork Marina: Cyanobacteria abundant in isolated chunks. Green color persistent throughout the water column.
  • Lindon Marina: Green cyanobacteria floating on the surface and within the water. Visible paint streaks on the surface of the water. Cyanobacteria appear to be well distributed throughout the water column. Scum visible along the shoreline. Water darker green closer to the shore.
  • Lincoln Marina: Cyanobacteria form a surface scum along the shoreline. Bloom thick and mostly green with some browns and milky-white colors. Surface scum isolated along the beach, but green clumps of cyanobacteria observed floating further out into the Marina.
  • Two miles west of Vineyard Buoy: Small green particulate cyanobacteria floating on the surface of the water. Cyanobacteria well dispersed along the surface of the water. Consistent layer of isolated chunks along the surface of the water. Cyanobacteria not appearing to be well distributed through the water column.
  • One mile west of Provo Harbor Buoy: Small green particulate cyanobacteria floating on the surface of the water. Cyanobacteria well dispersed along the surface of the water. Consistent layer of isolated chunks along the surface of the water. Cyanobacteria not appearing to be well distributed through the water column.
  • Open water: Clumps of green cyanobacteria floating on the top of the water. Clumps dispersed and isolated.
  • Bird Island Buoy: Clumps of green cyanobacteria floating on the top of the water. Clumps dispersed and isolated.

The northern end of the lake appeared mostly free of cyanobacteria accumulation. However, the marinas ( American Fork, Lindon, and Lincoln) were still thick with cyanobacteria accumulation. Isolated clumps of green cyanobacteria were observed in the water along the southern portion of the lake, mostly around the Bird Island buoy area.

Warning and Danger Advisories remain in effect at Utah Lake.

Sample Location and Sample Type

  • American Fork Marina (surface sample)
  • Two miles west of Vineyard (surface sample)
  • One mile west of Provo Boat Harbor (surface sample)
  • Provo Bay Ski Dock (elbow-depth integrated composite sample)
  • One mile southeast of Bird Island (surface sample)
  • Lindon Marina (surface sample)
  • Lincoln Marina (surface sample)
  • Open water (surface sample)

Toxin Test Results

  • American Fork Marina: 0.31 micrograms per liter (µg/L) of anatoxin-a; >5 µg/L of microcystin
  • Two miles west of Vineyard: <0.10 µg/L of anatoxin-a; >5 µg/L of microcystin
  • One mile west of Provo Boat Harbor: 0.14 µg/L of anatoxin-a; >5 µg/L of microcystin
  • Provo Bay Ski Dock: <0.10 µg/L of anatoxin-a; 0.63 µg/L of microcystin
  • One mile southeast of Bird Island: <0.10 µg/L of anatoxin-a; >5 µg/L of microcystin
  • Lindon Marina: 0.16 µg/L of anatoxin-a; >5 µg/L of microcystin
  • Lincoln Marina: 0.33 µg/L of anatoxin-a; >5 µg/L of microcystin
  • Open water: <0.10 µg/L of anatoxin-a; >5 µg/L of microcystin

Update September 26, 2018

The Utah Public Health Lab (UPHL) performed additional dilutions on two samples collected from Utah Lake on September 19, 2018. Final toxin results from the Bird Island Buoy sample after 1000x dilution showed microcystin levels of 430 micrograms per liter (µg/L). Final results from the sample near Pelican Point after 10x dilution showed microcystin levels of 19 µg/L.

Warning and Danger Advisories remain in effect for Utah Lake.


Update September 25, 2018

Lincoln Marina, September 19, 2018

The Division of Water Quality (DWQ) collected samples from eight locations on Utah Lake on September 19, 2018. Anatoxin-a levels exceeded recreation health-based thresholds for a Warning Advisory at two sample sites. Three sites exceeded recreation health-based levels for a Warning Advisory for microcystins, including microcystin levels of >500 micrograms per liter (µg/L) near Bird Island after 100x dilution and >5 µg/L near Pelican Point. These two samples will require further dilutions by the lab to quantify microcystin concentrations, and preliminary values could go even higher after these dilutions.

Four sites had noticeable blooms:

  • Lindon Marina: Green cyanobacteria were present on the surface of the water as a scum through most of the marina. Accumulation of cyanobacteria was especially thick along the shores.
  • Lincoln Marina: Green cyanobacteria were present on the surface of the water through most of the marina. Accumulation of cyanobacteria was especially thick along the southwest shore.
  • Bird Island Buoy: Clumps of green cyanobacteria were observed floating through the water. The clumps were well distributed but fairly abundant.
  • One mile east of Pelican Point: Faint green streaks of cyanobacteria were observed on the surface of the water.

Warning and Danger Advisories remain in effect for Utah Lake.

Sample Locations and Sample Types

  • Two miles west of Vineyard (elbow-depth integrated composite sample)
  • One mile west of Provo Boat Harbor (elbow-depth integrated composite sample)
  • Provo Bay Ski Dock (elbow-depth integrated composite sample)
  • One mile southeast of Bird Island (surface sample)
  • Lindon Marina (surface sample)
  • Lincoln Marina (surface sample)
  • One mile east of Pelican Point (surface sample)
  • Goshen Bay (surface sample)

Toxin Test Results (Utah Public Health Lab (UPHL)

  • Two miles west of Vineyard: 0.35 micrograms per liter (µg/L) of anatoxin-a; 0.91 µg/L of microcystins
  • One mile west of Provo Boat Harbor: <0.10 µg/L of anatoxin-a; 1.2 µg/L of microcystins
  • Provo Bay Ski Dock: <0.10 µg/L of anatoxin-a; 0.14 µg/L of microcystins
  • One mile southeast of Bird Island: <0.10 µg/L of anatoxin-a; >500 µg/L of microcystins
  • Lindon Marina: <0.10 µg/L of anatoxin-a; 15 µg/L of microcystins
  • Lincoln Marina: 0.15 µg/L of anatoxin-a: 470 µg/L microcystins
  • One mile east of Pelican Point: <0.10 µg/L of anatoxin-a; >5 µg/L of microcystins
  • Goshen Bay: <0.10 µg/L of anatoxin-a; 0.27 µg/L of microcystins

Update September 20, 2018

Toxin test results from samples collected at Utah Lake on September 11, 2018, confirmed visual observations by the Division of Water Quality (DWQ) during its visit. The DWQ monitoring crew reported that open water sites were mostly clear of blooms, although faint green streaks were observed on open water sites outside of Lindon Marina, at the Vineyard buoy, and the Bird Island buoy. These faint blooms were sparse and dispersed over the open water sites. All the marina sites visited displayed heavy cyanobacteria accumulation on the surface of the water.

Anatoxin-a levels exceeded the recreation health-based threshold for a Warning Advisory at the Vineyard buoy, Lindon Marina, Lincoln Marina, and American Fork Harbor. Microcystin levels exceeded recreation health-based levels for a Warning Advisory at four locations, including the Vineyard buoy and Lindon Marina, but were particularly high at the Bird Island buoy and American Fork Harbor.

Sample Locations and Sample Types

  • Open water-Utah Lake (surface sample)
  • Two miles west of Vineyard (surface sample)
  • One mile west of Provo Boat Harbor (elbow-depth integrated composite sample)
  • Provo Bay Ski Dock (elbow-depth integrated composite sample)
  • One mile southeast of Bird Island (surface sample)
  • Lindon Marina (surface sample)
  • Lincoln Marina (surface sample)
  • American Fork Harbor (surface sample)

Toxin Test Results

Test results are from both the Utah Public Health Lab (UPHL) and Utah Department of Agriculture and Food (UDAF) lab.

  • Open water-Utah Lake: 0.14 micrograms per liter (µg/L)of anatoxin-a (UDAF); 1.5 µg/L of microcystins (UPHL)
  • Two miles west of Vineyard: 0.12 µg/L of anatoxin-a; 4.6 µg/L of microcystins (UPHL)
  • One mile west of Provo Boat Harbor:<0.10 µg/L of anatoxin-a; 0.73 µg/L of microcystins (UPHL)
  • Provo Bay Ski Dock: <0.10 µg/L of anatoxin-a; <0.10 µg/L of microcystins (UPHL)
  • One mile southeast of Bird Island: <0.10 µg/L of anatoxin-a; 140 µg/L of microcystins (100x dilution) (UPHL)
  • Lindon Marina: 0.37 µg/L of anatoxin-a; 28 µg/L of microcystins (10x dilution)(UPHL)
  • Lincoln Marina: 0.59 µg/L of anatoxin-a (UDAF); no results available yet for microcystins
  • American Fork Harbor: 0.17 µg/L of anatoxin-a; 89 µg/L of microcystins (100x dilution) (UPHL)

The current Danger and Warning Advisories for Utah Lake remain in effect.


Update September 14, 2018

The Division of Water Quality (DWQ) recently received cyanobacteria cell-count results for the September 5, 2018, samples. All but one location exceeded the recreation health-based threshold for a Warning Advisory. Lincoln and Lindon Marinas continue to have high cyanobacteria cell-count densities.

Cyanobacteria Cell-Count Concentrations

  • Two miles west of Vineyard: 30,131 cells per milliliter (cells/ml)
  • One mile west of Provo Boat Harbor: 60,069 cells/ml
  • Provo Bay Ski Dock: 2,688 cells/ml
  • One mile east of Bird Island: 88,009 cells/ml
  • Lindon Marina: 730,248 cells/ml
  • Lincoln Marina: 1,347,097 cells/ml

Warning and Danger Advisories remain in place for Utah Lake.


Update September 10, 2018

The Division of Water Quality (DWQ) sampled six sites on Utah Lake on September 5, 2018. Open water bloom conditions were much improved over the previous week, but marina sites displayed active bloom conditions. With the exception of Lindon Marina, anatoxin-a levels were below the recreation health-based threshold. Microcystin levels were also below the recreation health-based threshold at four of the six sites, but Lindon Marina and Lincoln Marina continued to show high microcystin levels.

DWQ received updated toxin-test results over the weekend for its August 28, 2018, samples on Utah Lake. Further dilutions by the Utah Public Health Lab (UPHL) quantified microcystin levels for three of four samples that exceeded the upper limits of the original toxin test. All samples exceeded the recreation health-based threshold for a Warning Advisory. Two samples showed high microcystin levels: a sample collected at Lincoln Marina contained 200 micrograms per liter (µg/L) (75x dilution) of microcystin, and a sample collected in the open water contained microcystin levels >500 µg/L after 100x dilution. The lab will continue to dilute the open-water sample for further quantification of microcystin levels.

Cyanobacteria cell-count concentrations from August 28, 2018, sampling ranged from approximately 3 million cells per milliliter (cells/ml) in the open water to approximately 15,000 cells/ml near Bird Island. Cell counts at four of the six sites exceeded the recreation health-based threshold for a Warning Advisory.

Warning and Danger Advisories remain in effect.

Sample Locations and Sample Types

September 5, 2018

  • Two miles west of Vineyard (elbow-depth integrated composite sample) (buoy site)
  • One mile west of Provo Boat Harbor (elbow-depth integrated composite sample) (buoy site)
  • Provo Bay Ski Dock (elbow-depth integrated composite sample)
  • One mile east of Bird Island (elbow-depth integrated composite sample) (buoy site)
  • Lindon Marina (surface sample)
  • Lincoln Marina (surface sample)

August 28, 2018

  • Two miles west of Vineyard (elbow-depth integrated composite sample) (buoy site)
  • One mile west of Provo Boat Harbor (elbow-depth integrated composite sample) (buoy site)
  • Provo Bay Ski Dock (elbow-depth integrated composite sample)
  • One mile east of Bird Island (elbow-depth integrated composite sample) (buoy site)
  • Lincoln Marina (surface sample)
  • Utah Lake Open Water (surface sample)

Toxin-Test Results

September 5, 2018

Utah Department of Agriculture and Food (UDAF) results

  • Two miles west of Vineyard: <0.10 micrograms per liter (µg/L) of anatoxin-a; 0.87 µg/L of microcystin
  • One mile west of Provo Boat Harbor: <0.10 µg/L of anatoxin-a; 0.82 µg/L of microcystin
  • Provo Bay Ski Dock: <0.10 µg/L of anatoxin-a; 0.19 µg/L of microcystin
  • One mile east of Bird Island: <0.10 µg/L of anatoxin-a; 1.32 µg/L of microcystin
  • Lindon Marina: 0.29 µg/L of anatoxin-a; >5 µg/L of microcystin
  • Lincoln Marina: <0.10 µg/L of anatoxin-a; 243.6 µg/L of microcystin (50x dilution)

August 28, 2018

Utah Public Health Lab (UPHL) results

  • Two miles west of Vineyard: <0.10 µg/L of anatoxin-a; 5.43 µg/L of microcystin
  • One mile west of Provo Boat Harbor: <0.10 µg/L of anatoxin-a; 55.2 µg/L of microcystin
  • Provo Bay Ski Dock: 0.16 µg/L of anatoxin-a; <0.10 µg/L of microcystin
  • One mile east of Bird Island: <0.10 µg/L of anatoxin-a; 3 µg/L of microcystin
  • Lincoln Marina: <0.10 µg/L of anatoxin-a; 200 µg/L of microcystin
  • Utah Lake Open Water: <0.10 µg/L of anatoxin-a; >500 µg/L of microcystin

Cyanobacteria Cell-Count Concentrations

  • Two miles west of Vineyard: 117,935 cells per milliliter (cells/ml)
  • One mile west of Provo Boat Harbor: 216,745 cells/ml
  • Provo Bay Ski Dock: 17,375 cells/ml
  • One mile east of Bird Island: 15,165 cells/ml
  • Lincoln Marina: 1,179,156 cells/ml
  • Utah Lake Open Water: 3,044,663 cells/ml

Update September 4, 2018

Further toxin testing by the Utah Public Health Lab (UPHL) on samples collected by the Division of Water Quality (DWQ) on August 28, 2018, show high microcystin levels at Lincoln Marina and in the open water at the lake. Microcystin levels are increasing throughout the lake, particularly in the open water.

UPHL toxin testing showed 200 micrograms per liter (µg/L) of microcystins at Lincoln Marina and >150 µg/L of microcystins in the open water after 30x dilution. The lab will continue to dilute the sample for final quantification of microcystin levels. Should portions of the bloom remain intact and move towards the Jordan River, there could be widespread impact to the river and its canals. The Salt Lake County Health Department (SLCoHD) continues to sample the Jordan River to monitor current conditions.

DWQ will send a crew to Utah Lake tomorrow to sample these sites. Warning and Danger Advisories remain in effect.

Toxin Test Results

Test results are from UPHL unless otherwise noted.

  • Two miles west of Vineyard (buoy): <0.10 µg/L of anatoxin-a; >5 µg/L of microcystin
  • One mile west of Provo Boat Harbor (buoy): <0.10 µg/L of anatoxin-a (UPHL); >25 µg/L of microcystin (Utah Department of Agriculture and Food (UDAF) lab)
  • Provo Bay Ski Dock: 0.16 µg/L of anatoxin-a; 0.33 µg/L of microcystin (UDAF)
  • One mile southeast of Bird Island (buoy): <0.10 µg/L of anatoxin-a (UPHL); >5 µg/L of microcystin (UDAF)
  • Lincoln Marina: <0.10 µg/L of anatoxin-a; 200 µg/L of microcystin (75x dilution)
  • Utah Lake open water: <0.10 µg/L of anatoxin-a: >150 µg/L of microcystin (30x dilution)

Update August 31, 2018

The Division of Water Quality (DWQ) collected six samples at open-water and shoreline access sites on August 28, 2018. Toxin test results from the Utah Department of Agriculture and Food (UDAF) lab showed that anatoxin-a levels at two sites and microcystin samples at five sites exceeded the recreation health-based threshold for a Warning Advisory. All four open water sample sites showed microcystin levels >5 µg/L. The sample at the buoy 1 mile west of the Provo Boat Harbor showed microcystin levels >25 µg/L after 5x dilution. The Lincoln Marina location was also >5 µg/L. Further dilutions by the lab will be necessary to quantify microcystin concentrations.

Sample Sites and Sample Types

  • Two miles west of Vineyard (buoy) (surface sample)
  • One mile west of Provo Boat Harbor (buoy) (surface sample)
  • Provo Bay Ski Dock (elbow-depth integrated composite sample)
  • One mile southeast of Bird Island (buoy) (elbow-depth integrated composite sample)
  • Lincoln Marina (surface sample)
  • Utah Lake open water (surface sample)

Toxin Test Results

  • Two miles west of Vineyard (buoy): <0.1 micrograms per liter (µg/L) of anatoxin-a; >5 µg/L of microcystin
  • One mile west of Provo Boat Harbor (buoy): 0.12 µg/L of anatoxin-a; >25 µg/L of microcystin
  • Provo Bay Ski Dock: <0.1 µg/L of anatoxin-a; 0.33 µg/L of microcystin
  • One mile southeast of Bird Island (buoy): <0.1 µg/L of anatoxin-a; >5 µg/L of microcystin
  • Lincoln Marina: 0.12 µg/L of anatoxin-a; >5 µg/L of microcystin
  • Utah lake open water: 0.1 µg/L of anatoxin-a; >5 µg/L of microcystin

Warning and Danger Advisories for Utah Lake remain in effect.


Update August 27, 2018

Lincoln Marina, August 21, 2018

The Division of Water Quality (DWQ) collected samples at six locations on Utah Lake on August 21, 2018. Cyanobacteria cell-count concentrations at all six locations exceeded the recreation health-based threshold for a Warning Advisory.

While cyanobacteria cell-count densities at Lincoln Marina continued to be high (approximately 4 million cells per milliliter (cells/ml)), they were considerably lower than the 18.4 million cells/ml found in the August 14, 2018, sampling. However, microcystin levels at Lincoln Marina have increased from 7 micrograms per liter (µg/L) to 32.4 µg/L.

Toxin test results from the Utah Department of Agriculture and Food (UDAF) lab showed anatoxin-a levels exceeding the Warning Advisory threshold at four locations and microcystin levels exceeding the threshold at two sample locations.

Toxin test results from the Utah Public Health Lab for a sample collected at Lindon Marina on August 23, 2018, showed microcystin levels dropping significantly from previous weeks.

Sample Locations and Sample Types

  • Two miles west of Vineyard (elbow-depth integrated composite sample)
  • One mile west of Provo Boat Harbor (elbow-depth integrated composite sample)
  • Provo Bay Ski Dock (elbow-depth integrated composite sample)
  • One mile southeast of Bird Island (elbow-depth integrated composite sample)
  • Utah Lake open water (elbow-depth integrated composite sample)
  • Lincoln Marina (surface sample)
  • Lindon Marina (surface sample)

Cyanobacteria Cell-Count Concentrations

  • Two miles west of Vineyard: 103,979 cells per milliliter (cells/ml)
  • One mile west of Provo Boat Harbor: 69,996 cells/ml
  • Provo Bay Ski Dock: 77,063 cells/ml
  • One mile southeast of Bird Island: 118,471 cells/ml
  • Utah Lake open water: 654,811 cells/ml
  • Lincoln Marina: 3,990,401 cells/ml

Toxin Test Results

Test results reported by the Utah Department of Agriculture and Food (UDAF) lab for samples collected August 21, 2018

  • Two miles west of Vineyard: <0.1 micrograms per liter (µg/L) of anatoxin-a; 0.61 µg/L of microcystins (error in anatoxin-a test may affect results)
  • One mile west of Provo Boat Harbor: <0.1 µg/L of anatoxin-a; 0.96 µg/L of microcystins (error in anatoxin-a test may affect results)
  • Provo Bay Ski Dock: 0.25 µg/L of anatoxin-a; 0.62 µg/L of microcystins
  • One mile southeast of Bird Island: 0.27 µg/L of anatoxin-a; 1.4 µg/L of microcystins
  • Utah Lake open water: 0.26 µg/L of anatoxin-a: 4.03 µg/L of microcystins
  • Lincoln Marina: 0.67 µg/L of anatoxin-a; 32.4 µg/L of microcystins

Test results reported by the Utah Public Health Lab for a sample collected August 23, 2018

  • Lindon Marina: <0.10 µg/L of anatoxin-a; 0.71 µg/L of microcystins

Update August 23, 2018

Cyanobacteria cell-count concentration results from all samples collected at open-water access sites on August 15, 2018, showed cell counts exceeding the recreation health-based threshold for a Warning Advisory.. The highest cell-count densities of approximately 2.9 million cells per milliliter (cells/ml) were found in an open water sample.

Warning and Danger Advisories for Utah Lake remain in effect.

Cyanobacteria Cell Count Concentrations: Open-Water Access Samples

Samples were collected on August 15, 2018.

  • Two miles west of Vineyard: 63,396 cells per milliliter
  • One mile west of Provo Boat Harbor: 88,343 cells/ml
  • Provo Bay Ski Dock: 44,810 cells/ml
  • One mile southeast of Bird Island: 118,311 cells/ml
  • Open water: 2,951,252 cells/ml

Danger Advisory for Lincoln Marina/Lincoln Beach

A Danger Advisory indicates a high relative probability of acute health risk, cell count densities greater than 10,000,000 cells/ml, microcystins levels greater than 2,000 µg/L, cylindrospermopsin levels greater than 8 µg/L, or anatoxin-a levels greater than 90 µg/L. Closure of the waterbody is recommended.

Warning Advisory for Utah Lake

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.


Update August 22, 2018

The Utah County Health Department (UCHD) closed Utah Lake’s Lindon Marina today due to high cyanobacteria and toxin levels that pose a health risk to the public, pets, and other animals. Samples collected by the Division of Water Quality (DWQ) on August 14, 2018, showed cyanobacteria cell count-concentrations exceeding the recreation health-based threshold for a Danger Advisory. Utah County Health Department officials have posted Danger/Closed signs at Lindon Marina.

Results from the Lindon Marina water sample showed cyanobacteria cell-concentrations of 24 million cells per milliliter (cells/ml), well over the 10 million cells/ml threshold for a Danger Advisory.

Toxin tests conducted by the Utah Public Health Lab (UPHL) on the sample collected August 14, 2018, also showed extremely high levels of microcystin. Sample results showed 2,000 micrograms per liter (µg/L), which rests at the recreation health-based Danger Advisory threshold of >2,000 µg/L.

Danger Advisory for Lindon Marina, Lincoln Marina, and Lincoln Beach

A Danger Advisory indicates a high relative probability of acute health risk, cell count densities greater than 10,000,000 cells/ml, microcystins levels greater than 2,000 µg/L, cylindrospermopsin levels greater than 8 µg/L, or anatoxin-a levels greater than 90 µg/L. Closure of the waterbody is recommended.


Update August 21, 2018

Cyanobacteria cell-count concentrations from August 14, 2018, shoreline samples show extremely high cell counts, with Lindon Marina and Lincoln Marina both exceeding the recreation health-based threshold for a Danger Advisory/Closure. Sandy Beach cell counts of approximately 9 million cells per milliliter (cells/ml) approach but do not exceed the Danger Advisory threshold. The remaining cell-count densities range from approximately 1.76 million cells/ml to approximately 4.5 million cells/ml.

Cyanobacteria Cell Counts

  • Saratoga Springs Marina: 4,152,947 cells/ml
  • American Fork Beach: 4,522,098 cells/ml
  • Lindon Marina: 24,772,228 cells/ml
  • Utah State Park Marina : 1,757,671 cells/ml
  • Lincoln Marina: 18,404,054 cells/ml
  • Sandy Beach: 9,002,988 cells/ml

Danger Advisory for Lincoln Marina/Lincoln Beach

A Danger Advisory indicates a high relative probability of acute health risk, cell count densities greater than 10,000,000 cells/ml, microcystins levels greater than 2,000 µg/L, cylindrospermopsin levels greater than 8 µg/L, or anatoxin-a levels greater than 90 µg/L. Closure of the waterbody is recommended.

Warning Advisory for Utah Lake

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. Advisory actions:

  • Do not swim or water ski
  • Do not ingest the water
  • Keep pets and livestock away
  • Clean fish well and discard guts
  • Avoid areas of scum when boating

Update August 17, 2018

The Division of Water Quality (DWQ) collected samples at shoreline and open-water locations on Utah Lake on August 14 and 15, 2018. Overall, bloom conditions were worse at the majority of shoreline sites visited.

  • The eastern side of the lake showed much worse conditions than observed in prior monitoring visits. American Fork Marina and American Fork Beach both showed signs of a bloom. Lindon Marina also displayed bloom conditions on the north and south sides of the marina and within the marina. DWQ also observed a bloom within the Utah Lake State Park marina near the southern boat launch.
  • The Lincoln Marina/Beach area displayed blooms on both the north and south beaches as well as within the marina. Sandy Beach was also experiencing a bloom.
  • While the west side of the Saratoga Springs Marina displayed improved conditions, remnant clumps of cyanobacteria were mixed in with filamentous algae along the shore of the marina.

Toxin test results from the Utah Public Health Lab (UPHL) showed microcystin concentrations at Lindon Marina on the threshold of the recreation health-based levels for a Danger Advisory. Microcystin levels at American Fork Beach, Sandy Beach, and an open water location exceeded the recreation health-based threshold for a Warning Advisory. UPHL is re-testing the Lincoln Marina sample.

Danger Advisory for Lincoln Marina/Lincoln Beach

A Danger Advisory indicates a high relative probability of acute health risk, cell count densities greater than 10,000,000 cells/ml, microcystins levels greater than 2,000 µg/L, cylindrospermopsin levels greater than 8 µg/L, or anatoxin-a levels greater than 90 µg/L. Closure of the waterbody is recommended.

Warning Advisory for Utah Lake

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. Advisory actions:

  • Do not swim or water ski
  • Do not ingest the water
  • Keep pets and livestock away
  • Clean fish well and discard guts
  • Avoid areas of scum when boating

August 14, 2018: Shoreline Access Samples

  • Saratoga Springs Marina (surface sample)
  • American Fork Beach (surface sample)
  • Lindon Marina (surface sample)
  • Utah State Park Marina (surface sample)
  • Lincoln Marina (surface sample)
  • Sandy Beach (surface sample)

August 15, 2018: Open-Water Access Samples

  • Two miles west of Vineyard (elbow-depth integrated composite sample)
  • One mile west of Provo Boat Harbor (elbow-depth integrated composite sample)
  • Provo Bay Ski Dock (elbow-depth integrated composite sample)
  • One mile southeast of Bird Island (elbow-depth integrated composite sample)
  • Open water (elbow-depth integrated composite sample)

Toxin Test Results

The Utah Public Health Lab (UPHL) reported the following toxin test results for microcystin.

August 14, 2018: Shoreline Access Samples

  • Saratoga Springs Marina: 2.8 micrograms per liter (µg/L) of microcystin (2x dilution)
  • American Fork Beach: 4.8 µg/L of microcystin (10x dilution)
  • Lindon Marina: 2000 µg/L of microcystin (500x dilution)
  • Utah State Park Marina: 3.2 µg/L of microcystin
  • Lincoln Marina: Lab re-testing sample
  • Sandy Beach: 6.04 µg/L of microcystin (20x dilution)

August 15, 2018: Open-Water Access Samples

  • Two miles west of Vineyard: 0.63 µg/L of microcystin
  • One mile west of Provo Boat Harbor: 0.68 µg/L of microcystin
  • Provo Bay Ski Dock: 0.14 µg/L of microcystin
  • One mile southeast of Bird Island: 0.39 µg/L of microcystin
  • Open water: 4.9 µg/L of microcystin (10x dilution)

Update August 15, 2018

Lab results for samples collected on August 6 and 8, 2018, show very high cyanobacteria cell counts at Lincoln Marina (approximately 42 million cells per milliliter (cells/ml) and Lincoln Beach (approximately 15 million cells/ml) along with elevated microcystin levels at both locations. High microcystin levels were also found at Sandy Beach and Provo Boat Harbor.

Cyanobacteria cell counts at Lincoln Marina and Lincoln Beach exceed the recreation health-based threshold for a Danger Advisory. Cell counts at all other shoreline-access locations and all open-water locations exceed the recreation health-based threshold for a Warning Advisory.

Microcystin levels were quite high at some shoreline locations and twice the recommended recreation health-based threshold in one open water sample. Microcystin levels ranged from 97 micrograms per liter (µg/L) at Lincoln Marina to 8.2 µg/L at the buoy one mile from the Utah Lake State Park. Anatoxin-a levels were relatively low, but samples from the Utah Lake State Park, two miles west of Vineyard, outside Provo Bay, and one mile southeast of Bird Island exceeded the recreation health-based threshold for a Warning Advisory.

The Utah County Health Department (UCHD) has closed Lincoln Marina and Lincoln Beach based on the high cyanobacteria cell counts and microcystin levels. The Warning Advisory for the rest of the lake remains in place.

Danger Advisory for Lincoln Marina/Lincoln Beach

A Danger Advisory indicates a high relative probability of acute health risk, cell count densities greater than 10,000,000 cells/ml, microcystins levels greater than 2,000 µg/L, cylindrospermopsin levels greater than 8 µg/L, or anatoxin-a levels greater than 90 µg/L. Closure of the waterbody is recommended.

Warning Advisory for Utah Lake

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. Advisory actions:

  • Do not swim or water ski
  • Do not ingest the water
  • Keep pets and livestock away
  • Clean fish well and discard guts
  • Avoid areas of scum when boating

Sampling Locations and Sample Types

August 6, 2018—Shoreline Access Locations

Test results from the Utah Public Health Lab (UPHL)

  • Sandy Beach: <0.10 µg/L of anatoxin-a; 23 µg/L of microcystin
  • Swedes Access 100 meters off Boat Launch: <0.10 µg/L of anatoxin-a; 0.33 µg/L of microcystin
  • Utah Lake State Park north of dike: 0.16 µg/L of anatoxin-a; 0.87 µg/L of microcystin
  • Lincoln Marina: <0.10 µg/L of anatoxin-a; 233 µg/L of microcystin (100x dilution)
  • Lincoln (south) Beach: <0.10 µg/L of anatoxin-a; 67 µg/L of microcystin (50x dilution)

August 8, 2018—Open Water Locations

  • Utah Lake open water (elbow-depth integrated composite sample)
  • Two miles west of Vineyard (elbow-depth integrated composite sample)
  • Outside Provo Bay (elbow-depth integrated composite sample)
  • One mile southeast of Bird Island (elbow-depth integrated composite sample)
  • One mile west of Provo Boat Harbor (elbow-depth integrated composite sample)
  • Utah Lake open water (elbow-depth integrated composite sample)

Cyanobacteria Cell-Count Concentrations

August 6, 2018—Shoreline Access Locations

  • Sandy Beach: 5,436,876 cells per milliliter (cells/ml)
  • Swedes Access 100 meters off Boat Launch: 51,307 cells/ml
  • Utah Lake State Park north of dike: 37,991 cells/ml
  • Lincoln Marina: 42,109,864 cells/ml
  • Lincoln Beach: 14,808,678 cells/ml

August 8, 2018—Open Water Locations

  • Utah Lake open water: not submitted
  • Two miles west of Vineyard: 74,374 cells/ml
  • Outside Provo Bay: 95,979 cells/ml
  • One mile southeast of Bird Island: 21,133 cells/ml
  • One mile west of Provo Boat Harbor: 61,227 cells/ml
  • Utah Lake open water: 2,541,587 cells/ml

Toxin Test Results

August 6, 2018—Shoreline Access Locations

Test results from the Utah Department of Agriculture and Food (UDAF) lab.

  • Sandy Beach: <0.10 µg/L of anatoxin-a; 15.7 µg/L of microcystin
  • Swedes Access 100 meters off Boat Launch: <0.10 µg/L of anatoxin-a; 0.3 µg/L of microcystin
  • Utah Lake State Park north of dike: <0.10 µg/L of anatoxin-a; 0.87 µg/L of microcystin
  • Lincoln Marina: <0.10 µg/L of anatoxin-a; 97 µg/L of microcystin
  • Lincoln Beach: <0.10 µg/L of anatoxin-a; 59.5 µg/L of microcystin

August 8, 2018—Open Water Locations

Test results from the Utah Public Health Lab.

  • Utah Lake open water: <0.10 µg/L of anatoxin-a; 4.3 µg/L of microcystin
  • Two miles west of Vineyard: 0.11 µg/L of anatoxin-a; 0.5 µg/L of microcystin
  • Outside Provo Bay: 0.13 µg/L of anatoxin; 0.78 µg/L of microcystin
  • One mile southeast of Bird Island: 0.11 µg/L of anatoxin-a; 3.5 µg/L of microcystin
  • One mile west of Provo Boat Harbor: <0.10 µg/L of anatoxin-a; 8.2 µg/L of microcystin
  • Utah Lake open water: <0.10 µg/L of anatoxin-a; 1.7 µg/L of microcystin

Update August 10, 2018

The Division of Water Quality collected samples on August 6, 2018, at five locations on Utah Lake. While anatoxin-a levels were very low, microcystin levels at three of the five sample sites were well above the recreation health-based threshold for a Warning Advisory.

Warning Advisory for Utah Lake

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. Advisory actions:

  • Do not swim or water ski
  • Do not ingest the water
  • Keep pets and livestock away
  • Clean fish well and discard guts
  • Avoid areas of scum when boating

Sample Locations and Sample Types

  • Sandy Beach (surface sample)
  • Swedes Access 100 meters off Boat Launch (surface sample)
  • Utah Lake State Park north of the dike (surface sample)
  • Lincoln Marina (surface sample)
  • Lincoln South Beach (surface sample)

Toxin Test Results

The Utah Department of Agriculture and Food (UDAF) lab provided toxin test results for the August 6, 2018, samples. The lab had to dilute three of the samples 20 times to determine the actual levels of microcystin since toxin concentrations were greater than the upper limits of the test.

  • Sandy Beach: <0.1 micrograms per liter (µg/L) of anatoxin-a; 15.7 µg/L of microcystin (20x dilution)
  • Swedes Access 100 meters off Boat Launch: <0.1 µg/L of anatoxin-a; 0.3 µg/L of microcystin
  • Utah Lake State Park north of the dike: <0.1 µg/L of anatoxin-a; 0.87 µg/L of microcystin
  • Lincoln Marina: <0.1 µg/L of anatoxin-a; 97 µg/L of microcystin (20x dilution)
  • Lincoln South Beach:<0.1 µg/L of anatoxin-a; 59.5 µg/L of microcystin (20x dilution)

Update August 8, 2018

Division of Water Quality (DWQ) monitoring staff collected samples at all Utah Lake marinas and several open-water locations on July 30 and July 31, 2018. The crew noted that Sandy Beach had noticeable paint streaks in the shallow area, but Swedes Access did not have a visible surface bloom. Lincoln Marina continues to have a bloom and appears to be experiencing a bloom north of the dike. The Saratoga Springs Marina area had a bloom for the first time this season.

Lincoln Marina. Click for larger view

Cyanobacteria cell count densities exceeded the recreation health-based threshold in all but two sampling sites. Cell counts were especially high at Sandy Beach (over 2.5 million cells per milliliter (cells/ml), Lincoln Marina (over 6.5 million cells/ml), and Saratoga Springs (over 1.4 million cells/ml).

Toxin test results from the Utah Public Health Lab (UPHL) showed microcystin levels >5 micrograms per liter (µg/L) at Sandy Beach, Lincoln Marina, and the Saratoga Springs Marina. These levels exceed the recreational health-based threshold for microcystin. UPHL will conduct additional dilutions/testing to determine the actual levels of microcystin since toxin concentrations are greater than the upper limits of the test.

Recent satellite imagery of the lake indicates that the bloom has expanded lake-wide. Based on this imagery, high cyanobacteria cell counts, and toxin exceedances at locations on the east and west sides of the lake, the Utah County Health Department has issued a Warning Advisory for all of Utah Lake.

DWQ monitoring crews have visited the lake several times this week. Data from these latest samples should be available early next week.

Warning Advisory for Utah Lake

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. Advisory actions:

  • Do not swim or water ski
  • Do not ingest the water
  • Keep pets and livestock away
  • Clean fish well and discard guts
  • Avoid areas of scum when boating

Satellite Images of Utah Lake

Sample Locations and Sample Types

July 30, 2018

  • Sandy Beach (surface sample)
  • Swedes Access 100 meters off the boat launch (surface sample)

July 31, 2018

  • Utah Lake State Park north of dike (surface sample)
  • Lincoln Marina (surface sample)
  • Provo Bay Ski Dock (elbow-depth integrated composite sample)
  • One mile southeast of Bird Island (elbow-depth integrated composite sample)
  • Two miles west of Vineyard (elbow-depth integrated composite sample)
  • Saratoga Springs Marina (elbow-depth integrated composite sample)

Cyanobacteria Cell-Count Concentrations

Cell-count densities exceeded the recreation health-based threshold for a Warning Advisory in all but two sampling sites.

July 30, 2018

  • Sandy Beach: 2,559,265 cells per milliliter (cells/ml)
  • Swedes Access 100 meters off the boat launch: 118,408 cells/ml

July 31, 2018

  • Utah Lake State Park north of dike: 7,805 cells/ml
  • Lincoln Marina: 6,534,446 cells/ml
  • Provo Bay Ski Dock: 79,933 cells/ml
  • One mile southeast of Bird Island: 18,516 cells/ml
  • Two miles west of Vineyard: 40,422 cells/ml
  • Saratoga Springs Marina: 1,425,058 cells/ml

Toxin Test Results

Microcystin levels were above the recreation health-based threshold at Sandy Beach, Lincoln Marina, and Saratoga Springs. Since toxin concentrations are greater than the upper limits of the test, actual levels of microcystin could be significantly higher.

July 30, 2018

  • Sandy Beach: <0.1 µg/L of anatoxin-a; >5 µg/L of microcystin
  • Swedes Access 100 meters off the boat launch: <0.1 µg/L of anatoxin-a; 0.4 µg/L of microcystin

July 31, 2018

  • Utah Lake State Park north of dike: <0.1 µg/L of anatoxin-a; 0.53 µg/L of microcystin
  • Lincoln Marina: <0.1 µg/L of anatoxin-a; >5 µg/L of microcystin
  • Provo Bay Ski Dock: strip test non-detect for anatoxin-a; 0.48 µg/L of microcystin
  • One mile southeast of Bird Island: strip test non-detect for both anatoxin-a and microcystin
  • Two miles west of Vineyard: strip test non-detect for anatoxin-a; 0.76 µg/L of microcystin
  • Saratoga Springs Marina: strip test non-detect for anatoxin-a; >5 µg/L of microcystin

Update August 1, 2018

Division of Water Quality (DWQ) monitoring crews collected samples on July 24, 2018, in locations in Utah Lake currently under a Warning Advisory. Conditions are improving, particularly cell-count densities at Lincoln Marina, but cyanobacteria cell-count concentrations and toxin levels continue to remain above recreational health-based thresholds at Lincoln Marina, Sandy Beach, and Provo Bay area.

DWQ monitoring crews collected samples on July 30 and 31, 2018, at seven Utah lake locations. Toxin strip test results were either non-detect or invalid. Samples were sent to the Utah Public Health Lab and Utah Department of Agriculture and Food (UDAF) lab for toxin testing and Phycotech for cyanobacterial cell-count concentrations and taxa identification. DWQ will post an update once it receives test results.

Warning Advisory for Portions of Utah Lake

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. Advisory actions:

  • Do not swim or water ski
  • Do not ingest the water
  • Keep pets and livestock away
  • Clean fish well and discard guts
  • Avoid areas of scum when boating

Sample Locations and Sample Type

  • Lincoln Marina (surface sample)
  • Sandy Beach (surface sample)
  • Swedes Access 100 meters off Boat Launch (surface sample)
  • Utah Lake State Park North of Dike (elbow-depth, integrated composite sample)

Cyanobacteria Cell-Count Concentrations

  • Lincoln Marina: 227,346 cells per milliliter (cells/ml)
  • Sandy Beach: 85,005 cells/ml
  • Swedes Access 100 meters off Boat Launch: 80,734 cells/ml
  • Utah Lake State Park North of Dike: 8,575 cells/ml

Toxin Test Results

  • Lincoln Marina: 0.17 micrograms per liter (µg/L) of anatoxin-a; 4.8 µg/L of microcystin
  • Sandy Beach: 0.14 µg/L of anatoxin-a; 2.9 µg/L of microcystin
  • Swedes Access 100 meters off Boat Launch: 0.13 µg/L of anatoxin-a
  • Utah Lake State Park North of Dike: <0.1µg/L of anatoxin-a; 0.25 µg/L of microcystin

Update July 26, 2018

The Utah County Health Department reopened the Lincoln Marina today after two consecutive weeks of test results show cyanobacteria cell-count concentrations dropped below the threshold for a Danger Advisory. The Lincoln Marina continues to exceed the recreation health-based threshold for primary contact with water and has been placed under a Warning Advisory.

Utah Department of Health/Utah Department of Environmental Quality Health Advisory Guidance recommends two consecutive weeks of sampling data to downgrade a harmful algal bloom (HAB) health advisory on a waterbody.

Lincoln Marina sampling data show the cyanobacteria cell-count concentrations are now below the 10 million cells per milliliter (cells/ml) threshold for a Danger Advisory:

  • July 16, 2018 sampling results: 3,420,881 cells/ml
  • July 9, 2018 sampling results: 7,898 cells/ml

However, July 16, 2018, cell-count densities and microcystin levels of 17.4 micrograms per liter (µg/L) still exceed the recreation health-based threshold, which warrants a Warning Advisory for the marina.


Update July 20, 2018

Division of Water Quality (DWQ) monitoring crews collected samples at four locations on Utah Lake on July 16, 2018. Crews observed a thick green scum at the surface at Lincoln Marina with pea-soup green water below it, indicating that the bloom there is ongoing. The other sample sites either showed faint hints of a bloom or no visible bloom.

Cyanobacteria cell-count densities have increased since July 9, 2018, sampling and continue to exceed the recreational health-based threshold. Microcystin levels at Lincoln Marina exceeded the recreational health-based threshold, but laboratory toxin test results from all other sample locations tested below the threshold. The Warning Advisory remains in place for portions of the lake.

Warning Advisory for Portions of Utah Lake

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. Advisory actions:

  • Do not swim or water ski
  • Do not ingest the water
  • Keep pets and livestock away
  • Clean fish well and discard guts
  • Avoid areas of scum when boating

Sample Locations and Sample Types

  • Lincoln Marina (surface)
  • Sandy Beach (surface)
  • Swedes Access (surface)
  • Utah State Park north of dike (elbow-depth integrated composite sample)

Cyanobacteria Cell-Count Concentrations

Cell-count densities generally trended upward since the July 9, 2018 samples, and exceed recreational health-based thresholds at all sample locations.

  • Lincoln Marina: 3,420,881 cells per milliliter (cells/ml)
  • Sandy Beach: 235,538 cells/ml
  • Swedes Access: 110,831 cells/ml
  • Utah State Park north of dike: 28,030 cells/ml

Lab Toxin Test Results

Samples were submitted to the Utah Public Health Lab (UPHL) and Utah Department of Agriculture and Food (UDAF) labs for enzyme-linked immunosorbent assay (ELISA) testing. Results listed below are from UDAF. All sites were below the recreational health-based threshold for anatoxin-a. Lincoln Marina exceeded the health-based threshold for microcystin; all other sample sites were below the threshold for microcystin.

  • Lincoln Marina: <0.1 micrograms per liter (µg/L) of anatoxin-a; 17.4 µg/L of microcystin
  • Sandy Beach: <0.1 µg/L of anatoxin-a; 1.37 µg/L of microcystin
  • Swedes Access:<0.1 µg/L of anatoxin-a; 0.1 µg/L of microcystin
  • Utah State Park north of dike: <0.1 µg/L of anatoxin-a; <0.1 µg/L of microcystin

Update July 13, 2018

Division of Water Quality (DWQ) monitoring crews have been collecting samples on the shorelines and open waters in Utah Lake over the past two weeks. On July 9, 2018, crews observed visible improvements in the southern portion of the lake, with no visible bloom at Lincoln Marina and less noticeable bloom activity at Sandy Beach. Phycocyanin readings were also lower than previous weeks. Late afternoon storms and winds appear to be limiting growth, but bloom activity could increase if weather patterns change, and calm, stagnant lake conditions return.

Samples collected on July 2, 2018, show that toxigenic cyanobacteria cell counts continue to exceed health-based thresholds at Lincoln Marina, with over 17 million cells per milliliter (cells/ml). Swedes Access (>229,000 cells/ml) and outside Provo Bay (>85,000 cells/ml) also exceed health-based thresholds. Microcystin levels at Lincoln Marina are >50 micrograms per liter (µg/L). DWQ is waiting for further dilutions by the lab to accurately quantify the microcystin level at Lincoln Marina, which remains closed. Even though cell counts have dropped below recreation health thresholds at the Utah Lake State Park, the July 2, 2018, sample contained 0.17 µg/L anatoxin-a, so it remains a recreational health risk.

While some areas on Utah Lake are not currently affected by blooms, algae may move or disperse depending on temperature, wind, and weather. Recreationists are advised to be mindful of conditions, as they may change over the course of the day.

Warning Advisory for Portions of Utah Lake

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. Advisory actions:

  • Do not swim or water ski
  • Do not ingest the water
  • Keep pets and livestock away
  • Clean fish well and discard guts
  • Avoid areas of scum when boating

July 9, 2018 (July 10, 2018, for Middle of Provo Bay)

Cyanobacteria cell-count concentrations and toxin test results for anatoxin-a continue to exceed recreational health-based thresholds.

Sample Locations and Sample Types

  • Lincoln Marina (surface sample)
  • Sandy Beach (surface sample)
  • Swedes Access (surface sample)
  • Utah Lake State Park north of dike (surface sample)
  • Middle of Provo Bay

Cell Count Concentrations

Cell count densities have dropped significantly at Lincoln Marina, from well over 17 million cells per milliliter (cells/ml) in the July 2, 2108, sample to just under 8,000 cells/ml in the July 9, 2018, sample. Cyanobacteria cell-count concentrations continue to exceed recreational health-based thresholds at Swedes Access and the middle of Provo Bay.

  • Lincoln Marina: 7,898 cells per milliliter (cells/ml)
  • Sandy Beach: 16,713 cells/ml
  • Swedes Access: 110,651 cells/ml
  • Utah Lake State Park north of dike: 6,991 cells/ml
  • Middle of Provo Bay: 103,614 cells/ml

Toxin Strip Test Results

  • Middle of Provo Bay: <0.4 µg/L for anatoxin-a; non-detect for microcystin

Lab Toxin Test Results

Samples were submitted to the Utah Public Health Lab (UPHL) and Utah Department of Agriculture and Food (UDAF) labs for enzyme-linked immunosorbent assay (ELISA) testing. Results listed below are from UDAF. Toxin levels exceeded recreational health-based thresholds for anatoxin-a at several locations.

  • Lincoln Marina: 0.19 micrograms per liter (µg/L) for anatoxin-a: 1 µg/L for microcystins
  • Sandy Beach: <0.10 µg/L for anatoxin-a; 0.32 µg/L for microcystins
  • Swedes Access: <0.10 µg/L for anatoxin-a; 0.26 µg/L for microcystins
  • Utah Lake State Park north of dike: <0.10 µg/L for anatoxin-a; 0.13 µg/L for microcystins
  • Middle of Provo Bay: 0.16 µg/L for anatoxin-a

July 2, 2018 (July 3, 2018, for Sandy Beach)

Test results from samples taken in early July indicate that conditions continue to warrant a Warning Advisory in areas currently under an advisory. Very low levels of anatoxin-a have been detected at additional sites, but no additional advisories are in place.

Sample Locations and Sample Types

  • Lincoln Marina (surface sample)
  • Swedes Access (elbow-depth integrated composite sample)
  • One mile east of Bird Island
  • Two miles west of Vineyard
  • One mile west of Provo Boat Harbor
  • Outside Provo Bay (surface sample)
  • Outside Provo Bay (elbow-depth integrated composite sample)
  • Utah Lake State Park north of dike
  • Sandy Beach

Cell Count Concentrations

  • Lincoln Marina: 17,792,475 cells per milliliter (cells/ml)
  • Swedes Access: 229,106 cells/ml
  • One mile east of Bird Island: 7,038 cells/ml
  • Two miles west of Vineyard: 9,025 cells/ml
  • One mile west of Provo Boat Harbor: 5,595 cells/ml
  • Outside Provo Bay: 85, 315 cells/ml
  • Outside Provo Bay: (elbow-depth integrated composite sample): not submitted
  • Utah Lake State Park north of dike: 8,979 cells/ml
  • Sandy Beach: 55,045 cells/ml

Toxin Strip Test Results

  • Lincoln Marina: non-detect for anatoxin-a; >10 micrograms per liter (µg/L) for microcystin
  • Swedes Access: 0.4 µg/L for anatoxin-a; non-detect for microcystin
  • One mile east of Bird Island: non-detect for both anatoxin-a and microcystin
  • Two miles west of Vineyard: non-detect for both anatoxin-a and microcystin
  • One mile west of Provo Boat Harbor: non-detect for both anatoxin-a and microcystin
  • Outside Provo Bay (surface sample): 0.4 µg/L for anatoxin-a; non-detect for microcystin
  • Outside Provo Bay (elbow-depth integrated composite sample): non-detect for both anatoxin-a and microcystin
  • Utah Lake State Park north of dike: 0.4 µg/L for anatoxin-a; non-detect for microcystin
  • Sandy Beach: no strip test

Lab Toxin Test Results

Samples were submitted to the Utah Public Health Lab (UPHL) and Utah Department of Agriculture and Food (UDAF) labs for enzyme-linked immunosorbent assay (ELISA) testing.

Tests results were fairly comparable. Listed below are data from the UDAF lab.

  • Lincoln Marina: <0.10 µg/L for anatoxin-a; >50 µg/L for microcystin
  • Swedes Access: <0.10 µg/L for anatoxin-a; 0.55 µg/L for microcystin
  • One mile east of Bird Island: <0.10 µg/L for anatoxin-a; 0.73 µg/L for microcystin
  • Two miles west of Vineyard: <0.10 µg/L for anatoxin-a; 0.23 µg/L for microcystin
  • One mile west of Provo Boat Harbor: no sample submitted
  • Outside Provo Bay (surface sample): <0.10 µg/L for anatoxin-a; 3.5 µg/L for microcystin
  • Outside Provo Bay (elbow-depth integrated composite sample); <0.10 µg/L for anatoxin-a; 3.5 µg/L for microcystin
  • Utah Lake State Park north of dike: 0.17 µg/L for anatoxin-a; 0.31 µg/L for microcystin
  • Sandy Beach: <0.10 µg/L for anatoxin-a; 0.41 µg/L for microcystin

Update June 29, 2018

The Utah County Health Department (UCHD) closed the Lincoln Marina today due to exceptionally high cyanobacteria cell-count concentrations. UCHD also posted Danger/Closure signs in the Lincoln Beach area.

Swedes Access (Provo Bay), the State Park Day Use Area, and Sandy Beach areas continue to be under a Warning advisory.

The Division of Water Quality (DWQ) collected samples on June 25, 2018, at four locations on Utah Lake that are currently under a health-based recreational warning advisory. Laboratory confirmation of toxin levels and cell-count densities at Swedes Access (Provo Bay), the State Park Day Use Area, Sandy Beach, and Lincoln Marina showed that these areas continue to exceed recommended health-based recreational advisory levels for cell concentrations/toxin levels.

The situation at Lincoln Marina has worsened considerably since last week, with cell-count densities in the June 25, 2018, sample containing concentrations 14 times greater than the June 20, 2018 sample. Cell-count concentrations at Lincoln Marina currently exceed the recommended recreational health-based threshold for a DANGER advisory. In addition, enzyme-linked immunosorbent assay (ELISA) toxin testing by the Utah Department of Agriculture and Food (UDAF) lab showed microcystin levels of >500 µg/L after a 100x dilution. Toxin levels could prove to be even higher after further dilutions.

Toxin Test Results

Toxin test results from the UDAF lab for samples collected on June 25, 2018, showed high levels of microcystins at Swedes Access and Sandy Beach and extremely high levels of microcystins at Lincoln Marina.

  • Swedes Access (Provo Bay): 7.9 micrograms per liter (µg/L)
  • State Park Day Use Area: Non-detect
  • Sandy Beach: 11.3 µg/L
  • Lincoln Marina: >500 µg/L

Microcystin values for the June 25, 2018 sample in Lincoln Marina may increase after further laboratory dilutions/analysis.

Cell-count Concentrations

Dolichospermum, a particularly toxic cyanobacteria, was the primary cyanobacteria genus present in the samples. Dolichospermum made up 98 percent of the Lincoln Marina sample, which explains the extremely high toxin levels found in the June 25, 2018, sample. All cell-count concentrations exceed the recommended recreational health thresholds for a Warning advisory, and Lincoln Marina cell-count concentrations exceed the recommended recreational health-based threshold for a Danger advisory.

  • Swedes Access (Provo Bay): >2.8 million cells per milliliter (cells/ml)
  • State Park: 30,989 cells/ml
  • Sandy Beach: 617,850 cells/ml
  • Lincoln Marina: >36 million cells/ml (well above the recommended recreational health-based threshold of 10 million cells/ml)

Update June 26, 2018

The Division of Water Quality (DWQ) received updated test results today on samples collected on Utah Lake on June 20, 2018. DWQ crews also collected samples at Lincoln Marina, Sandy Beach, the Utah Lake State Park, and Swede Access on June 25, 2018, to track the progression of the bloom.

The Utah Public Health Lab (UPHL) ran 10x dilutions on samples with microcystin concentrations greater than the upper limit of the test (5 micrograms per liter (µg/L)). Dilutions help analysts determine the final result of a sample with high levels of toxins. Currently, DWQ knows that microcystin concentrations in the Lincoln Marina and Sandy Beach samples collected June 20, 2018, were at least >50 µg/L. A final result value for these samples is expected by June 29, 2018.

Cell-count concentrations from the June 20, 2018, samples were also very high at the State Park Day Use Area, Lincoln Marina, and Sandy Beach. All samples were dominated by Dolichospermum, a regularly toxic genus of cyanobacteria.

DWQ crews collecting samples on June 25, 2018, noticed visual improvements in all sampling areas with the exception of Lincoln Marina, which appeared to be worse.

Warning Advisory for Portions of Utah Lake

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. Advisory actions:

  • Do not swim or water ski
  • Do not ingest the water
  • Keep pets and livestock away
  • Clean fish well and discard guts
  • Avoid areas of scum when boating

Cyanobacteria Cell Count Concentrations

All samples from June 20, 2018, were dominated by Dolichospermum. The following cell counts were for toxigenic cyanobacteria only.

  • Lincoln Marina: >2.5 million cells per milliliter (cells/ml)
  • Sandy Beach: >1.4 million cells/ml
  • State Park Day Use Area: >539,000 cells/ml

Samples collected on June 25, 2018, have been sent to the lab for cell-count concentrations and taxa identification.

Toxin Test Results

June 20, 2018

Updated results following 10x dilutions are listed below. UPHL will be running another round of tests at the end of the week on the Lincoln Marina and Sandy Beach samples.

  • Lincoln Marina: >50 µg/L. Retest on June 29, 2018.
  • Sandy Beach: >50 µg/L. Retest on June 29, 2018.
  • Utah State Park Day Use Area: 17 µg/L

June 25, 2018

Toxin test strips only. Samples will be sent to UPHL for further toxin testing and to Phycotech for cyanobacteria cell counts and taxa identification. All samples were non-detect for anatoxin-a.

  • Lincoln Marina: >10 µg/L
  • Sandy Beach: Error
  • Utah State Park Day Use Area: non-detect
  • Swede Access:  ̴ 2.5 µg/L

DWQ will continue to conduct weekly surveys along the lake’s shorelines and within the lake.


Update June 25, 2018

The Utah County Health Department (UCHD) has issued a Warning Advisory for Utah Lake in four areas of the lake due to toxin levels that exceed health-based thresholds in Utah Department of Health/Utah Department of Environmental Quality (UDOH-UDEQ) guidance.

UCHD advises people, their pets, and other animals to stay out of the following areas of Utah Lake:

  • Provo Bay
  • Lincoln Marina
  • Sandy Beach
  • Utah Lake State Park Day Use Area

The health department is currently posting warning signs at the affected locations. Division of Water Quality (DWQ) scientists are collecting additional samples at these locations today.

DWQ conducted sampling on June 20, 2018, at eight Utah Lake sites (see previous update for more detailed information). Toxin test-strip results from three of the sample sites exceeded the recommended health advisory threshold for microcystins. Utah Public Health Lab enzyme-linked immunosorbent assay (ELISA) testing confirmed the toxin test-strip results.
While some areas on Utah Lake are not currently affected by the blooms, algae may move or disperse depending on temperature, wind, and weather. Recreationists are advised to be mindful of conditions, as they may change over the course of the day.

Warning Advisory for Portions of Utah Lake

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. Advisory actions:

  • Do not swim or water ski
  • Do not ingest the water
  • Keep pets and livestock away
  • Clean fish well and discard guts
  • Avoid areas of scum when boating

Toxin Test Results

ELISA testing by the Utah Public Health Lab showed the following microcystin levels in the June 20, 2018, Utah Lake water samples:

  • Lincoln Marina: >5.0 micrograms per liter (µg/L)
  • Sandy Beach: >5.0 µg/L
  • Utah State Park Day Use Area: >5.0 µg/L
  • Swede Access: 4.3 µg/L

All samples were surface samples (areas of scum). Further updates will be available soon on the orders of magnitude above 5.0µg/L microcystins for samples from Lincoln Marina, Sandy Beach, and Utah State Park.

Update June 21, 2018

On June 20, 2018, Division of Water Quality (DWQ) scientists visited eight Utah Lake sites during their regular monitoring to observe conditions and conduct sampling in areas that appeared to be experiencing harmful algal growth. Toxin test-strip results from three of the sample sites exceeded the recommended health advisory threshold for microcystins. Areas found to be exceeding the toxin thresholds are:

  • Lincoln Marina area
  • Sandy Beach area
  • Utah Lake State Park Day Use Area

Sites Visited

DWQ monitoring crews visited the following Utah Lake locations:

  • Saratoga Springs
  • Jordan Narrows
  • American Fork Harbor
  • Lindon Marina
  • Lincoln Marina
  • Utah Lake State Park
  • Sandy Beach
  • Swede Sportsman Access

The monitoring crew observed cyanobacteria accumulation in some portions of the lake, especially in the southern part of the lake at Lincoln Marina, Sandy Beach, and portions of Utah Lake State Park.

Sample Sites

Based on crew observations, DWQ collected nine samples at five sites:

  • Lincoln Marina
    • Surface sample
    • Integrated (elbow-depth composite sample)
  • Sandy Beach
    • Surface sample
    • Integrated (elbow-depth composite sample)
  • Utah Lake State Park Day Use Area
    • Surface sample
    • Integrated (elbow-depth composite sample)
  • Swede Sportsman Access 100 meters (m) off boat launch
    • Surface sample
    • Integrated (elbow-depth composite sample)
  • Swede Sportsman Access
    • Surface sample

Toxin Test-Strip Results

All sampling sites tested non-detect for anatoxin-a. Microcystin test results for the sample sites:

  • Lincoln Marina
    • Surface sample: >10 micrograms per liter (µg/L)
    • Integrated (elbow-depth composite sample): >5 µg/L
  • Sandy Beach
    • Surface sample: >10 µg/L
    • Integrated (elbow-depth composite sample): non-detect
  • Utah Lake State Park Day Use area
    • Surface sample: >7.5 µg/L
    • Integrated (elbow-depth composite sample) non-detect
  • Swede Sportsman Access 100 meters (m) off boat launch
    • Surface sample: > 2.5 µg/L
    • Integrated (elbow-depth composite sample): non-detect
  • Swede Sportsman Access
    • Surface sample: non-detect

Samples with positive results for microcystins have been sent to the Utah Public Health Lab and the Utah Department of Agriculture and Food lab for enzyme-linked immunosorbent assay (ELISA) testing. These results should be available early next week. Samples have also been sent to Phycotech for cyanobacteria cell-count concentrations and taxa identification.


Update June 12, 2018

The Utah County Health Department (UCHD) is warning the public to stay out of Provo Bay after DEQ sampling showed toxin and cyanobacteria levels that exceeded health-based thresholds. UCHD is posting warning signs at the Swede Sportsman Access near Provo Bay.

DEQ water-quality crews responded on June 6, 2018, to a report of an algal bloom in Provo Bay and collected five samples at various locations at and around the Swede Sportsman Access. Sample results detected the presence of two cyanotoxins, anatoxin-a and microcystin, with one sample at the Swede Sportsman Access (5.5 micrograms per liter (ug/L) microcystin) exceeding the Utah Department of Health/ Utah Department of Environmental Quality health-based threshold for recreational waters. All three samples sent to the lab for cell-count concentrations exceeded the health-based threshold, with cell counts ranging from approximately 400,000 cells per milliliter (cells/ml) to more than 21 million cells/ml. The cell count is an indication of harmful levels of cyanobacteria.

See the June 9, 2018, update for further details.

Warning Advisory for Provo Bay

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. Advisory actions:

  • Do not swim or water ski
  • Do not ingest the water
  • Keep pets and livestock away
  • Clean fish well and discard guts
  • Avoid areas of scum when boating

Provo Bay Map. Click for full view.


Update June 9, 2018

The Division of Water Quality (DWQ) collected samples at major public access points on Utah Lake on May 31, 2018. All samples were below toxin and cyanobacteria cell-count thresholds.

On June 6, 2018, DWQ responded to a report of a potential harmful algal bloom (HAB) along the south shore of Provo Bay near the Swede Sportsman Access. The division collected five samples, many of which exceeded the recommended health thresholds for toxins and cell-count concentrations under Utah Department of Health/Utah Department of Environmental Quality health guidance for HABs.

Sampling and Test Results

May 31, 2018

DWQ collected samples at the following six public access points on Utah Lake:

  • Utah Lake Outlet (Jordan River)
  • Saratoga Springs Marina
  • American Fork Beach
  • State Park Day-Use Area
  • Lindon Beach
  • Lincoln Marina

All were well below health thresholds under Utah Department of Health/Utah Department of Environmental Quality health guidance for HABs.

June 6, 2018

DWQ collected five samples near the Swede Sportsman Access:

  • 150 meters (m) west of the Ski Dock Provo Bay (surface-level sample)
  • 150 m west of the Ski Dock Provo Bay (elbow-depth integrated sample)
  • Swede Sportsman Access 100 m off launch Provo Bay (surface-level sample)
  • Swede Sportsman Access 100 m off launch Provo Bay (elbow-depth integrated sample)
  • Swede Sportsman Access Provo Bay (surface-level sample)

Surface-level samples are collected when the bloom has formed a mat or scum layer on the water surface.

Three samples were submitted for cyanobacteria cell counts and taxa identification. Sample results identified Dolichospermum as the primary genus in the bloom.

Microcystin was detected in all samples, with one sample containing 5.5 micrograms per liter (µg/L) of microcystin, exceeding the 4 µg/L threshold under Utah Department of Health/Utah Department of Environmental Quality health guidance for HABs. Anatoxin-a was detected in three of the five samples, also exceeding the threshold under Utah Department of Health/Utah Department of Environmental Quality health guidance.

The three samples submitted for cell-count concentrations all exceeded the threshold of 20,000 cells per milliliter (cells/ml) under the health guidance, with the sample containing 5.5 µg/L of microcystin also containing >21 million cells/ml.

Toxin results by sample site:

  • 150 meters (m) west of the Ski Dock: 0.12 µg/L of anatoxin-a; 0.19 µg/L of microcystin
  • 150 m west of the Ski Dock: <0.10 anatoxin-a; 0.18 µg/L of microcystin
  • Swede Sportsman Access 100 m off launch: 0.1 µg/L of anatoxin-a; 0.4 µg/L of microcystin
  • Swede Sportsman Access 100 m off launch: <0.10 µg/L of anatoxin-a: 0.22 µg/L of microcystin
  • Swede Sportsman Access: 0.13 µg/L of anatoxin-a; 5.5 µg/L of microcystin

Toxigenic cyanobacteria cell counts by sample site:

  • 150 meters (m) west of the Ski Dock: 397,769 cells/ml
  • Swede Sportsman Access 100 m off launch: 399,502 cells/ml
  • Swede Sportsman Access: 21,861,192 cells/ml

DWQ plans to conduct sample collection on other parts of Utah Lake (open water areas) beginning June 11, 2018.


Update May 15, 2018

On April 21, 2018, satellite imagery interpolation suggested cyanobacteria cell counts above the recommended recreational health thresholds. The suspected bloom didn’t appear to be lake-wide and was most pronounced in the northern portion of the lake from Saratoga Springs to Lindon Marina.

Sampling

Division of Water Quality (DWQ) scientists collected samples at five locations on May 3, 2018:

  • Saratoga Springs Marina
  • American Fork Marina
  • Lindon Marina
  • Jordan River outlet
  • State Park Harbor

The monitoring crew reported that the water looked moderately clean at the sample collection sites. While satellite imagery and buoy network data showed a spike in cyanobacteria activity earlier in the week, both showed this activity was low when samples were taken.

Test Results

All five samples were shipped to Phycotech for cell counts and genera/species identification and tested in-house for cyanotoxins. Toxin test strips were non-detect for microcystin at all five locations but anatoxin-a results were suspect. Therefore, all five samples were sent to the Utah Department of Agriculture (UDAF) lab for further anatoxin-a analysis.

On May 8, the UDAF Lab confirmed that anatoxin-a was not detected for all samples and PhycoTech reported no detections of cyanobacteria cells.

It appears that a localized cyanobacteria population grew and disappeared quickly. This kind of activity is not surprising since it’s early in the season and cyanobacteria in the lake haven’t established a baseline population yet. DWQ plans to conduct weekly routine HAB monitoring on Utah Lake beginning May 14, 2018.