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Utah Lake Algal Bloom 2017

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Update July 14, 2017

Expedited testing of six of the 12 samples collected on July 11, 2017, showed that all but one of the six sites sampled were above the threshold for a warning advisory. Four of these locations — Utah Lake State Park Buoy, Geneva Discharge, Goshen Bay, and Middle of Provo Bay — were above 100,000 cells per milliliter (cells/ml). The Goshen Bay sample contained approximately 322,000 cells/ml, with the Middle of Provo Bay sample not far behind at approximately 290,000 cells/ml.

Selection of the six priority samples was based on the sample locations that provided the best spatial representation of lake conditions and the resources available for expedited testing.

DWQ sent the 12 samples collected on July 11, 2017, to the Utah Public Health Lab after toxin strip tests confirmed the presence of microcystin and anatoxin-a. These toxin levels met the Utah Department of Health (UDOH) and DEQ health-based thresholds for a warning advisory but not for closure of a waterbody. The Utah lab’s test results, received July 14, 2017, were consistent with the rapid strip test results for microcystin. Samples have been sent to GreenWater Labs for confirmation of anatoxin-a rapid strip test results.

As of July 12, 2017, Utah Poison Control Center (UPCC) has reported a total of 68 cases related to the bloom. Fifty-five of those cases reported were human, with about 24 percent of the human cases symptomatic. Most common symptoms were gastrointestinal distress, dizziness, and skin irritation.

Warning Advisory for the majority of Utah Lake

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

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

Other recommendations

According to the Utah Department of Agriculture and Food (UDAF), the levels of cyanotoxins in Utah Lake are not considered a health threat to livestock at this time. UDAF will continue to monitor data and provide direction to the agriculture community as cyanotoxin concentrations change. The UDAF advises livestock owners to locate an alternative source of water should cyanotoxins rise to unhealthy levels in the future. UDAF also advises producers to fence off access points to areas with the potential for blooms, as livestock may prefer scums over clean water.

Sampling date and locations

July 11, 2017

DWQ collected samples at 12 locations across the lake.

  • Goshen Bay southwest end
  • Three miles west-northwest of Lincoln Beach
  • One mile northeast of Lincoln Point
  • One mile southeast of Bird Island (buoy)
  • Outside entrance to Provo Bay
  • Middle of Provo Bay
  • One mile west of State Park Harbor (Provo Marina) (buoy)
  • One mile east of Pelican Point
  • Two miles east of Saratoga Springs
  • One-half mile west of Geneva discharge
  • Two miles west of Vineyard (buoy)
  • North of State Park Buoy

Number of samples

July 11, 2017: 12 total; six expedited for cell count concentrations

Cell count concentrations

Cell-count concentrations posted here are for the six expedited samples.

  • Goshen Bay southwest end: 322,460 cells/ml
  • Middle of Provo Bay: 290,442 cells/ml
  • One mile west of State Park Harbor (Provo Marina) (buoy): 182,888 cells/ml
  • One mile east of Pelican Point: 12,458 cells/ml
  • Two miles east of Saratoga Springs: 27,872 cells/ml
  • One-half mile west of Geneva discharge: 112,912 cells/ml

Taxonomy

Multiple cyanobacteria taxa capable of producing toxins are present at different locations in the lake. Aphanizomenon is the dominant genera in samples at the three buoys. Dolichospermum is the dominant genera in the sample halfway between Provo Bay and State Park Harbor, which is consistent with previous samples in the vicinity of Provo Bay. Both are typically high-toxin producers for microcystin and anatoxin-a. Other taxa present in the most recent samples include Microcystis, Anabaena, and Planktothrix.

Toxins

  • July 11, 2017: Preliminary strip test results showed anatoxin levels of either 0.4 or 1.0 micrograms per liter (µg/L) at all sample sites, and microcystin levels of 1 µg/L at five sample sites. Utah Public Health Lab tests for microcystin met reportable detection levels and were consistent with the rapid strip test results. Strip tests were non-detect for cylindrospermopsin.

    Anatoxin-a levels were at the very low end of the warning-advisory threshold for anatoxin-a; however, any results above non-detect trigger a warning advisory under UDOH and DEQ health-based guidance. Microcystin levels were below the threshold for a warning advisory. Samples have been sent to GreenWater labs to confirm anatoxin-a levels.

Note that toxin levels can change rapidly.


Update July 12, 2017

Samples collected on Utah Lake on July 6, 2017, and July 11, 2017, along with current satellite imagery, show the algal bloom has expanded to cover the majority of the lake.

July 12, 2017

The Division of Water Quality (DWQ) sampled twelve locations on the lake on July 11, 2017. DWQ hopes to have cell-count concentration results from these samples on July 14, 2017.

Toxin strip tests for the July 11, 2017, samples confirm the presence of microcystin and anatoxin-a, but at levels below Utah Department of Health (UDOH) and DEQ health-based thresholds for closure of a waterbody. DWQ has sent these samples to the Utah Public Health Lab and GreenWater Labs for confirmation testing.

July 6, 2017

Cell-count concentrations from four, open-water samples collected by researchers from Brigham Young University (BYU) on July 6, 2017, fell within the warning-advisory threshold, with concentrations ranging from a low of approximately 68,000 cells per milliliter (cells/ml) one mile west of the Provo Marina to a high of approximately 603,000 cells/ml at the Vineyard Buoy.. Sample results were consistent with satellite images from July 4 to July 7, 2017, which showed the bloom spreading and increasing in density in the southern and western portions of the lake.

Warning Advisory for the majority of Utah Lake

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

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

Other recommendations

According to the Utah Department of Agriculture and Food (UDAF), the levels of cyanotoxins in Utah Lake are not considered a health threat to livestock at this time. UDAF will continue to monitor data and provide direction to the agriculture community as cyanotoxin concentrations change. The UDAF advises livestock owners to locate an alternative source of water should cyanotoxins rise to unhealthy levels in the future. UDAF also advises producers to fence off access points to areas with the potential for blooms, as livestock may prefer scums over clean water.

Sampling dates and locations

July 11, 2017

DWQ collected samples at twelve locations across the lake.

  • Goshen Bay southwest end
  • Three miles west-northwest of Lincoln Beach
  • One mile northeast of Lincoln Point
  • One mile southeast of Bird Island (buoy)
  • Outside entrance to Provo Bay
  • Middle of Provo Bay
  • One mile west of State Park Harbor (Provo Marina) (buoy)
  • One mile east of Pelican Point
  • Two miles east of Saratoga Springs
  • One-half mile west of Geneva discharge
  • Two miles west of Vineyard (buoy)
  • North of State Park Buoy

July 6, 2017

BYU researchers collected samples at the three Utah HAB Network buoys and halfway between Provo Bay and State Harbor.

  • Two miles west of Vineyard
  • One mile west of Bird Island
  • One mile west of Provo Marina
  • Halfway between Provo Bay and State Park

Number of samples

  • July 11, 2017: 12
  • July 6, 2017: 4
  • July 3, 2017: 6

Cell-count concentrations

Cell-count concentrations posted here include confirmation of preliminary sampling results from July 3, 2017.

Results Map July 6, 2017
Sampling-Update July 12, 2017

July 6, 2017 samples

  • Two miles west of Vineyard: 602,734 cells/ml
  • One mile west of Bird Island: 119,022 cells/ml
  • One mile west of Provo Marina: 68,095 cells/ml
  • Halfway between Provo Bay and State Park: 320,425 cells/ml

July 3, 2017 samples

Cell-count concentrations were confirmed on July 11, 2017.

  • Lincoln Beach: 0 cells/ml (Note: while cells counts were 0 at Lincoln Beach on July 3, 2107, visual inspections show bloom growth since that date. These observations are consistent with the fluctuating nature of the bloom.)
  • Sandy Beach: 59,427 cells/ml
  • Lindon Harbor: 1,399 cells/ml
  • American Fork Harbor: 1,913 cells/ml
  • State Park Harbor: 251 cells/ml
  • Jordan Narrows: 2,390 cells/ml

Taxonomy

Multiple cyanobacteria taxa capable of producing toxins are present at different locations in the lake. Aphanizomenon is the dominant genera in samples at the three buoys. Dolichospermum is the dominant genera in the sample halfway between Provo Bay and State Park Harbor, which is consistent with previous samples in the vicinity of Provo Bay. Both are typically high-toxin producers for microcystin and anatoxin-a. Other taxa present in the most recent samples include Microcystis, Anabaena, and Planktothrix.

Toxins

  • July 11, 2017: Preliminary strip test results showed anatoxin levels of either 0.4 or 1.0 micrograms per liter (µg/L) at all sample sites, and microcystin levels of 1 µg/L at five sample sites. Strip tests were non-detect for cylindrospermopsin.

    Anatoxin-a levels were at the very low end of the warning-advisory threshold for anatoxin-a; however, any results above non-detect trigger a warning advisory under UDOH and DEQ health-based guidance. Microcystin levels were below the threshold for a warning advisory.
  • July 6, 2017: Strip tests were non-detect for microcystin, cylindrospermopsin, and anatoxin-a.
  • July 3, 2017: Strip tests were non-detect for microcystin, cylindrospermopsin, and anatoxin-a.

Note that toxin levels can change rapidly.


Update July 8, 2017

Shoreline samples taken July 3, 2017, show generally lower levels of cyanobacteria than were present in the open water samples collected in late June 2017. The highest cell-count concentrations from the July 3, 2017, samples were found at Sandy Beach, with cell densities of 128,313 cells per milliliter (cells/ml). The Utah County Health Department posted temporary warning signs at Sandy Beach last weekend due to visibly increased scums along the shoreline, and the July 3, 2017, cell counts confirm that these scums were indicative of higher levels of cyanobacteria.

Researchers from Brigham Young University collected open-water samples on July 6, 2017. All samples tested non-detect for toxins. Cell-count concentration results from those samples should be available July 10-11, 2017.

Satellite images from July 4 to July 7, 2017, show the bloom spreading to the southern and western portions of the lake, with cell densities appearing to increase in the vicinity of Lincoln and Sandy Beach. Buoy data two miles west of Vineyard indicate increased cyanobacteria growth in the northern portion of the lake as well.

Shifting easterly and westerly winds over the past few days have moved the bloom over much of the lake, with cell densities fluctuating in certain areas due to this wind movement. Conditions at Sandy Beach, for example, have improved since the weekend, while conditions at Lincoln Beach showed increased bloom activity beginning July 6, 2017.

Since the bloom appears to be shifting to different areas of the lake, Utah County Health Department urges recreators to continue to use caution and avoid areas with scum, foam, or other visible signs of possible blooms.

Utah Poison Control Center (UPCC) reports a total of 31 cases since the bloom began. Of those reported, seven cases were symptomatic, primarily with gastrointestinal effects. Those reporting symptoms had recreated in Provo Bay, American Fork Harbor, and Lindon Marina.

According to the Utah Department of Agriculture and Food (UDAF), the level of cyanotoxins in Utah Lake is NOT considered a health threat to livestock at this time. UDAF will continue to track monitoring data and provide direction to the agricultural community as the cyanotoxin concentrations change and advises livestock owners to locate an alternative source of water should cyanotoxins rise to unhealthy levels in the future. UDAF also advises producers to fence off access points to areas with the potential for blooms, as livestock may prefer scums over clean water.

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 OR microcystins levels of 4-2,000 micrograms per liter (ug/L). Advisory actions:

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

Sampling dates and locations

July 6, 2017

Samples were collected by BYU at the Utah HAB Network buoys and Provo Airport site.

  • Two miles west of Vineyard
  • One mile west of Bird Island
  • One mile west of Provo Marina
  • West of the Provo Airport

July 3, 2017

Samples were collected at the following public access points and the Jordan Narrows.

  • Lincoln Beach
  • Sandy Beach
  • Lindon Marina
  • American Fork Marina
  • State Park Harbor
  • Jordan Narrows

Number of samples

  • July 6, 2017: four
  • July 3, 2017: six

Cell count: July 3, 2017 samples

Cell counts are preliminary but appear to be consistent with satellite imagery and visual inspections. Count results will be confirmed on July 10, 2017.

  • Lincoln Beach: 0 cells/ml (Note: while cells counts were 0 at Lincoln Beach on July 3, 2107, visual inspections show bloom growth in recent days. These observations are consistent with the fluctuating nature of the bloom.)
  • Sandy Beach: 128,313 cells/ml
  • Lindon Marina: 1,399 cells/ml
  • American Fork Marina: 1,913 cells/ml
  • State Park Harbor: 251 cells/ml
  • Jordan Narrows: 3,279 cells/ml

Taxonomy

Multiple cyanobacteria taxa are present, but samples in the vicinity of Provo Bay continue to be dominated by various species of Dolichospermum, including Dolichospermum crassum, Dolichospermum sigmoideum, and Dolichospermum flos-aquae. Dolichospermum is typically a high-toxin producer for microcystin and anatoxin-a. Aphanizomenon flos-aquae were present in the June 30, 2017, sample taken west of Vineyard, which may indicate that the northern area of the lake is experiencing a separate bloom that is merging with the bloom spreading north from Provo Bay.

Pseudanabaena, a lower toxin producer, was predominant in the shoreline sampling from July 3, 2017.

Toxins

  • July 6, 2017: Strip tests were non-detect for microcystin, cylindrospermopsin, and anatoxin-a.
  • July 3, 2017: Strip tests were non-detect for microcystin, cylindrospermopsin, and anatoxin-a.

Note that toxin levels can change rapidly.


Update: July 3, 2017

July 3, 2017

DWQ crews collected samples on Monday, July 3, 2017, at five public access points along Utah Lake from American Fork marina to Lincoln Beach and at the Jordan Narrows diversion. Toxin strip tests taken on all samples were non-detect for microcystin, cylindrospermopsin, and anatoxin-a.

Paired cell count sample results should be available on July 7, 2017.

June 30, 2017

Water Quality crews conducted sampling on June 30, 2017 (Excel document), at six locations from Provo Bay to the outlet to the Jordan River. Samples showed cyanobacteria cell concentrations exceeding 2.2 million cells per milliliter (cells/ml) in Provo Bay and 124,000 cells/ml in the open water one mile west of the Utah Lake State Park Harbor. Cyanobacteria concentrations were approaching 8,000 cells/ml in the northern part of the lake.

While cells counts in Provo Bay had dropped in the June 26, 2017, samples, concentrations increased dramatically in the June 30, 2017 samples, returning to levels above 2 million cells/ml. The cell concentrations in the open water one mile west of State Park Harbor also increased to over six times the threshold for a warning advisory.

Toxin strip tests for these samples were non-detect for microcystin, cylindrospermopsin, and anatoxin-a. Samples were also sent to the Utah State Health Lab for enzyme-linked immunosorbent assay (ELISA)-microcystin testing, a more precise measure of toxin concentration compared to strip tests.

Satellite images show the bloom continues to move north towards the Jordan River.

July 3: Map of HAB Results

According to the Utah Department of Agriculture and Food (UDAF), the level of cyanotoxins in Utah Lake is NOT considered a health threat to livestock at this time. UDAF will continue to track monitoring data and provide direction to the agricultural community as the cyanotoxin concentrations change and advises livestock owners to locate an alternative source of water should cyanotoxins rise to unhealthy levels in the future.

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 OR microcystins levels of 4-2,000 micrograms per liter (ug/L). Advisory actions:

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

Sampling Dates and Locations

July 3, 2017

Samples were collected at the following public access points and the Jordan Narrows:

  • Lincoln Beach
  • Sandy Beach
  • Lindon Marina
  • American Fork Marina
  • State Park Harbor
  • Jordan Narrows

June 30, 2017

The first four samples were submitted for cell counts and phytoplankton analysis. Crew members saw no evidence of the bloom north of State Harbor, so the samples near the outlet to the Jordan River and west of Geneva were tested for toxins only.

  • Provo Bay (middle of bay)
  • Mouth of Provo Bay
  • One mile west of State Park Harbor (buoy)
  • West of Vineyard (buoy)
  • Near outlet to Jordan River
  • West of Geneva

June 26, 2017

  • Provo Bay (middle of bay)
  • Mouth of Provo Bay
  • One mile west of State Park Harbor
  • Between State Park Harbor and Provo Bay

Number of samples

  • July 3, 2017: six
  • June 30, 2017: six
  • June 26, 2017: four

Cell count: June 30, 2017 samples

  • Provo Bay (middle of bay): ∼2.23 million cells/ml
  • Mouth of Provo Bay: ∼71,000 cells/ml
  • One mile west of State Park Harbor (buoy): ∼125,000 cells/ml
  • West of Vineyard (buoy): ∼8,000 cells/ml

Cell count: June 26, 2017 samples

  • Provo Bay (middle of bay): ∼193,000 cells/ml
  • Mouth of Provo Bay: ∼ 64,000 cells/ml
  • One mile west of State Park Harbor: ∼22,000 cells/ml
  • Between State Park Harbor and Provo Bay: ∼13, 000 cells/ml

Taxonomy

Multiple cyanobacteria taxa are present, but samples continue to be dominated by various species of Dolichospermum, including Dolichospermum crassum, Dolichospermum sigmoideum, and Dolichospermum flos-aquae. Dolichospermum is typically a high-toxin producer for microcystin and anatoxin-a.

Aphanizomenon flos-aquae were present in the June 30, 2017, sample taken west of Vineyard, which may indicate that the northern area of the lake is experiencing a separate bloom that is merging with the bloom spreading north from Provo Bay.

Toxins

  • June 30, 2017: Strip tests were non-detect for microcystin, cylindrospermopsin, and anatoxin-a.
  • June 26, 2017: Three of the samples were above the test detection/reporting level for microcystins (approximately 0.3 micrograms per liter (ug/L). These levels are below the EPA health-based threshold for recreational waters.

Note that toxin levels can change rapidly.


Update: June 30, 2017 - Provo Bay

Satellite images taken June 28, 2017, and June 29, 2017, indicate the algal bloom is spreading east and north from Provo Bay towards the Jordan River. This current bloom movement is following a similar pattern to last year’s bloom, with satellite photos showing increased concentrations along the lake’s eastern shore near American Fork Harbor and Lindon Harbor. If the bloom continues to spread northwest, it could reach the Jordan River in the next few days. Predicted wind patterns over the weekend could also shift the bloom to other portions of the lake.

The Division of Water Quality (DWQ), Utah County Health Department, and Salt Lake County Health Department are closely monitoring the situation. Water quality crews from DEQ are on Utah Lake today conducting sampling and visual inspections in areas outside Provo Bay. The Salt Lake County Health Department is monitoring the Jordan River and related canal systems, but did not observe any algal blooms on these waterways this afternoon.

Results from these samples and samples from earlier this week should be available on Monday.

The most recent test results indicate the presence of the cyanotoxin microcystin, but at levels well below the Environmental Protection Agency’s health-based threshold for recreational waters. Preliminary information available today suggests that cell counts in Provo Bay have declined but still remain within the range of a warning advisory.

State officials say the situation will be in flux for some time and advise recreationists to be mindful of the possible presence of algal blooms in other portions of Utah Lake. No warning advisories have been issued for other areas of the lake, but officials recommend that people recreating on the lake avoid areas of scum and not drink lake water.

June 27: European Space Agency Sentinel-2A/MSI: Provo Bay

June 29: Cyanobacteria Assessment Network and NOAA National Centers for Coastal Ocean Science

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 OR microcystins levels of 4-2,000 micrograms per liter (ug/L). Advisory actions:

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

Update: June 29, 2017 - Provo Bay

Recent sampling on Utah Lake by the Division of Water Quality (DWQ) confirmed the presence of an algal bloom in Provo Bay and surrounding areas. High cyanobacteria cell counts (Excel) prompted the Utah County Health Department to post a Warning Advisory today for Provo Bay.

DWQ conducted its routine monthly sampling on Utah Lake on June 12, 2017. Satellite imagery the following week indicated a bloom was developing in Provo Bay, so DWQ scientists returned to the area on June 22, 2017, for follow-up sampling.

Results from the June 22, 2017, samples showed high concentrations of cyanobacteria in Provo Bay and the mouth of the bay. Satellite imagery from June 28, 2017, indicated that the bloom is currently moving north from Provo Bay and extending westward across the lake.

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 OR microcystins levels of 4-2,000 micrograms per liter (ug/L).

Suzan Tahir, Environmental Scientist (DWQ) and Dax Reid, Provo River Watershed Coordinator (UDAF)

Advisory actions:

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

Sampling locations

Provo Bay and mouth of Provo Bay

Sampling dates

Provo Bay Samples

  • June 22, 2017
  • June 26. 2017

Number of samples

  • June 22, 2017: two
  • June 26, 2017: five

Cell count: June 22, 2017 samples

  • Provo Bay: >2.6M cells/ml (cells per milliliter) cyanobacteria
  • Mouth of Provo Bay: >51K cells/ml cyanobacteria

Taxonomy

European Space Agency Sentinel-2A/MSI: Provo Bay

Multiple cyanobacteria taxa are present, but both of the June 22, 2017, samples are dominated by Dolichospermum crassum which is typically a high-toxin producer for microcystin and anatoxin-a.

Toxins

  • June 26, 2017: Three of the samples were above the test detection/reporting level (Excel) for microcystins (approximately 0.3 micrograms per liter (ug/L). These levels are below the EPA health-based threshold for recreational waters.
  • June 22, 2017: Both of the samples were nondetect for microcystins.

Note that toxin levels can change rapidly.

DWQ collected additional samples on June 29, 2017, for toxin testing. The strip tests were nondetect for microcystin, cylindrospermopsin, and anatoxin-a. These samples will also be sent to the Utah State Health Lab for enzyme-linked immunosorbent assay (ELISA)-microcystin testing, a more precise measure of toxicity compared to strip tests.

Map from the Utah Department of Natural Resources