Browse the Data
- HAB Cyanobacteria Cell Count (October 16, 2017, Excel)
- HAB Cyanobacteria Cell Count (October 3, 2017, Excel)
- HAB Cyanobacteria Cell Count (September 26, 2017, Excel)
- HAB Cyanobacteria Cell Count (September 11, 2017, Excel)
- HAB Cyanobacteria Cell Count (September 5, 2017, Excel)
- HAB Cyanobacteria Cell Count (August 29, 2017, Excel)
- HAB Cyanobacteria Cell Count (August 22, 2017, Excel)
- HAB Cyanobacteria Cell Count (August 16, 2017, Excel)
- HAB Cyanobacteria Cell Count (August 14, 2017, Excel)
- Toxin Spreadsheet (August 14, 2017, Excel)
- Toxin Test Strip Spreadsheet (August 14, 2017, Excel)Strip tests and
- HAB Cyanobacteria Cell Count (August 7 and August 8, 2017, Excel)
- Toxin Spreadsheet (August 4 and August 8, 2017, Excel)
- HAB Cyanobacteria Cell Count (July 27, 2017, Excel)
- HAB Cyanobacteria Cell Count (July 18, 2017, Excel)
- HAB Cyanobacteria Cell Count (July 11, 2017, Excel)
- Toxin Test Strip Spreadsheet (July 11, 2017, Excel)
- HAB Cyanobacteria Cell Count (July 3 and 6, 2017, Excel)
- HAB Cyanobacteria Cell Count (June 30, 2017, Excel)
- Toxin Spreadsheet (June 26, 2017, Excel)
- Cell Counts (June 22, 2017, Excel)
Report a Bloom
24-Hour DEQ Environment Incidents Line: (801) 536-4123
Call Utah Poison Control Center
If you believe you or your pet have been exposed to a harmful algal bloom, call (800) 222-1222.
Update November 1, 2017
The sampling season for Utah Lake is coming to a close. The Division of Water Quality (DWQ) will conduct its monthly sampling later in November, but BYU researchers have concluded their weekly sampling of the lake for the season. The Utah County Health Department (UCHD) will begin removing warning signs from the lake later this week.
UCHD reminds users that the advisory is still in place and that the public-health risk from cyanobacteria exposure can linger after the bloom season is over. The health department urges people to continue to exercise caution when recreating on or near Utah Lake.
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 drink the water
- Keep pets and livestock away
- Clean fish well and discard guts
- Avoid areas of scum when boating
Update October 26, 2017
The Division of Water Quality (DWQ) collected samples on October 16, 2017, at eleven sites on the lake. Toxigenic cyanobacteria cell-count concentrations from three of these samples showed cell counts continuing to drop. Two of the three samples, however, still remain above the UDEQ-UDOH recommended health-advisory thresholds for a warning advisory.
DWQ conducted toxin strip test analyses at all eleven locations. Two locations — Bird Island Buoy and State Park Marina Buoy — had anatoxin-a detections of 0.4 micrograms per liter (µg/L). While these strip results for anatoxin-a were at the low end of the threshold for a warning advisory, any results above non-detect trigger a warning advisory under UDOH-UDEQ health-based guidance. DWQ also sent these two samples to the Utah Public Health Lab for ELISA testing for microcystin; both samples came in well below the health-based warning advisory for microcystin.
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 drink the water
- Keep pets and livestock away
- Clean fish well and discard guts
- Avoid areas of scum when boating
Sample Date and Locations
October 16, 2017
DWQ collected eleven samples across Utah Lake:
- Three miles west northwest of Lincoln Beach
- One mile northeast of Lincoln Point
- Middle of Provo Bay
- Two miles west of Vineyard
- One mile southeast of Bird Island
- Outside entrance to Provo Harbor
- One mile west of Provo Boat Harbor
- One mile east of Pelican Point
- Two miles east of Saratoga Springs
- One-half mile west of Geneva discharge
- Goshen Bay southeast end (collected October 17, 2017)
Number of Samples
October 16, 2017: 10
October 17, 2017: one
Cyanobacteria Cell-Count Concentrations
Samples from the three sites were sent to the lab for cyanobacteria cell-count concentrations and genera identification.
- Two miles west of Vineyard: 26,034 cells per milliliter (cells/ml)
- One mile east of Bird Island: 16,628 cells/ml
- Outside Provo Harbor: 44,492 cells/ml
Taxonomy
Several cyanobacteria taxa capable of producing toxins are present at sample locations on the lake. Aphanocapsa, Synechocystis and Dolichospermum were present in the samples collected October 16, 2017, although the cell-count densities for Dolichospermum were quite low. Microcystis and Aphanizomenon, both of which have been present in previous samples, were noticeably absent in the most recent sampling. Synechocystisis and Aphanocapsa are potential toxin producers for microcystin. Dolichospermum is a potential toxin producer for microcystin, anatoxin-a, and cylindrospermopsin.
Toxins
DWQ submitted two of the samples collected on October 16, 2017, to the Utah Public Health Lab for ELISA testing. Both samples were below the health-based warning advisory for microcystin.
- One mile east of Bird Island: 0.06 micrograms per liter (µ/L) of microcystin
- Outside Provo Harbor: 0.06 µ/L of microcystin
Update October 10, 2017
BYU researchers collected two samples on Utah Lake on October 3, 2017. High winds forced researchers off the lake early, so they only visited three sites, collected two samples, and conducted one toxin strip test. Cyanobacteria cell-count concentrations for the two samples were 30,028 cells per milliliter (cells/ml) and 49,771 cells/ml. These cell-count densities remain within the UDEQ-UDOH recommended health-advisory thresholds for a warning advisory. The toxin strip test at the Vineyard site was non-detect for microcystin and cylindrospermopsin, and 0.4 micrograms per liter (µ/L) for anatoxin-a. While the toxin test strip result for anatoxin-a was at the low end of the threshold for a warning advisory, any results above non-detect trigger a warning advisory under UDOH-UDEQ health-based guidance.
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 drink the water
- Keep pets and livestock away
- Clean fish well and discard guts
- Avoid areas of scum when boating
Sample Date and Locations
October 3, 2017
- Two miles west of Vineyard
- Outside of Lindon Marina
Number of Samples
October 3, 2017 (BYU): two
Cyanobacteria Cell-Count Concentrations
Both samples were sent to the lab for cyanobacteria cell-count concentrations and genera identification.
- Two miles west of Vineyard: 30,028 cells/ml
- Outside of Lindon Marina: 49,771 cells/ml
Taxonomy
Multiple cyanobacteria taxa capable of producing toxins are present at different locations in the lake. Aphanizomenon, Dolichospermum, Microcystis, Aphanocapsa, and Synechocystis were present in the Utah Lake samples collected October 3, 2017. Microcystis, Aphanizomenon, and Dolichospermum, are potential toxin producers for microcystin, anatoxin-a, and cylindrospermopsin. Synechocystisis and Aphanocapsa are potential toxin producers for microcystin.
Toxins
BYU researchers ran a toxin test strip on the Vineyard sample. The test results were non-detect for microcystin and cylindrospermopsin and 0.4 µ/L for anatoxin-a. While the toxin test strip result for anatoxin-a is at the low end of the threshold for a warning advisory, any results above non-detect trigger a warning advisory under UDOH-UDEQ health-based guidance.
Update October 4, 2017
BYU researchers collected eight samples on Utah Lake on September 26, 2017. Cyanobacteria cell-count concentrations in the six samples tested ranged from approximately 20,000 cells per milliliter (cells/ml) to approximately 113,000 cells/ml. These cell-count densities remain within the UDEQ-UDOH recommended health-advisory thresholds for a warning advisory. Toxin test strips taken on seven of the samples detected low levels of anatoxin-a at two sites. All sample sites tested were non-detect for microcystin and cylindrospermopsin. While the toxin strip-test results were at the low end of the warning-advisory threshold for anatoxin-a, any results above non-detect trigger a warning advisory under UDOH and UDEQ health-based guidance.
The Division of Water Quality (DWQ) collected three samples from two Utah Lake locations on September 27, 2017. All three samples tested below the health-based warning advisory for microcystin
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 drink the water
- Keep pets and livestock away
- Clean fish well and discard guts
- Avoid areas of scum when boating
Sample Date and Locations
September 26, 2017
BYU researchers collected eight samples at the following Utah Lake locations:
- One mile west of State Park Harbor
- Two miles west of Vineyard
- One mile east of Bird Island
- Outside entrance to Provo Bay
- One-half mile east of Saratoga Springs
- One-half mile west of Geneva discharge
- Two miles north of State Park Harbor
- Three-hundred-thirty meters northeast of Pelican Marina exit
September 27, 2017
DWQ collected three samples at two Utah Lake locations:
- State Park Marina (surface scum)
- State Park Marina (depth-integrated)
- Lindon Marina (depth-integrated)
Number of Samples
September 26, 2017 (BYU): eight
September 27, 2017 (DWQ): three
Cyanobacteria Cell-Count Concentrations
Samples from six of the eight sites were sent to the lab for cyanobacteria cell-count concentrations and genera identification.
- One mile west of State Park Harbor: 20,157 cells per milliliter (cells/ml)
- Two miles west of Vineyard: 45,049 cells/ml
- One mile east of Bird Island: 36,153 cells/ml
- Outside entrance to Provo Bay: 21,597 cells/ml
- Three-hundred-thirty meters northeast of Pelican Marina exit: 113,345 cells/ml
- One-half mile west of Geneva Discharge: 108,886 cells/ml
Taxonomy
Multiple cyanobacteria taxa capable of producing toxins are present at different locations in the lake. Aphanizomenon, Dolichospermum, Microcystis, Aphanocapsa, and Synechocystis were present in the Utah Lake samples collected September 26, 2017, particularly Aphanizomenon. Microcystis, Aphanizomenon, and Dolichospermum, are potential toxin producers for microcystin, anatoxin-a, and cylindrospermopsin. Synechocystisis and Aphanocapsa are potential toxin producers for microcystin.
Toxins
September 26, 2017
BYU researchers ran test strips on seven of the eight samples. Samples taken on September 26, 2017, near Saratoga Springs and the Geneva Discharge measured 1 microgram per liter (µ/L) of anatoxin-a. While these toxin test strip results are at the low end of the threshold for a warning advisory, any results above non-detect trigger a warning advisory under UDOH-UDEQ health-based guidance. All other samples tested non-detect for microcystin, cylindrospermopsin, and anatoxin-a.
- One mile west of State Park Harbor: non-detect
- Two miles west of Vineyard: non-detect
- One mile east of Bird Island: non-detect
- Outside entrance to Provo Bay: non-detect
- One-half mile east of Saratoga Springs: 1 µ/L anatoxin-a
- One-half mile west of Geneva Discharge: 1 µ/L anatoxin-a
- Two miles north of State Park Harbor: non-detect
September 27, 2017
DWQ submitted three samples collected on September 27, 2017, to the State Public Health Lab for ELISA testing. All samples were below the health-based warning advisory for microcystin.
- State Park Marina (surface scum): 1.59 ug/L microcystin
- State Park Marina (depth integrated): 0.18 ug/L microcystin
- Lindon Marina (depth integrated): 2.46 ug/L microcystin
Update September 20, 2017
Division of Water Quality (DWQ) scientists collected 10 samples at Utah Lake on September 11, 2017. Cyanobacteria cell counts were processed for the 3 routine locations associated with the WQ buoys.
Cyanobacteria Cell Counts
- 2 miles west of Vineyard: 37, 915 cells/ml
- 1 mile west of Utah Lake State Park Harbor: 57,478 cells/ml
- 1 mile southeast of Bird Island: 31,816 cells/ml
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, 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 drink the water
- Keep pets and livestock away
- Clean fish well and discard guts
- Avoid areas of scum when boating
Update September 13, 2017
Division of Water Quality (DWQ) scientists collected 10 samples at Utah Lake on September 11, 2017. Toxin strip tests were negative for all toxins for all samples, with the exception of a <0.4 micrograms per liter (µ/L) result at the Vineyard buoy. DWQ will send three of these samples to the lab for cyanobacteria cell-count concentrations and genera identification.
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, 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 drink the water
- Keep pets and livestock away
- Clean fish well and discard guts
- Avoid areas of scum when boating
Sample Date and Locations
September 11, 2017
DWQ collected samples at the following locations:
- Goshen Bay southwest end
- Three miles west-northwest of Lincoln Beach
- One mile northeast of Lincoln Point
- One mile southeast of Bird Island
- Outside entrance to Provo Bay
- One mile west of Provo Boat Harbor
- One mile east of Pelican Point
- Two miles east of Saratoga Springs
- 0.5 miles west of Geneva Discharge
- Two miles west of Vineyard
Number of Samples
September 11, 2017 (DWQ): 10
Toxins
While one sample taken on September 11, 2017, at the Vineyard buoy was at the low end of the warning-advisory threshold for anatoxin-a, any results above non-detect trigger a warning advisory under UDOH-UDEQ health-based guidance. All other samples tested non-detect for microcystin, cylindrospermopsin, and anatoxin-a.
Update September 12, 2017
Utah Lake
BYU researchers collected samples on Utah Lake on September 5, 2017. Lab results for samples from three of the four sites submitted for analysis showed that cyanobacteria cell-count concentrations had dropped significantly from the previous week. While cell-count densities decreased, they still remained within the UDEQ-UDOH health advisory thresholds for a warning advisory.
Warning Advisory for the majority of Utah Lake and Jordan River
A Warning Advisory indicates a moderate relative probability of acute health risk, cell count density of 20,000 -10 million cells per milliliter, 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 drink the water
- Keep pets and livestock away
- Clean fish well and discard guts
- Avoid areas of scum when boating
Sampling Date and Locations
Utah Lake Samples from four of the eight sites sampled were sent to the lab for cyanobacteria cell-count concentrations and genera identification.
September 5, 2017
- Two miles west of Vineyard
- One mile east of Bird Island
- One mile west of Provo Boat Harbor
- Two miles north of Provo Boat Harbor
Toxigenic Cyanobacteria Cell-Count Concentrations
Cell-count concentrations for four of the eight samples collected on the September 5, 2017, on Utah Lake:
- Two miles west of Vineyard: 41,457 cells per milliliter (cells/ml)
- One mile east of Bird Island: 22,037 cells/ml
- One mile west of Provo Boat Harbor: 20,085 cells/ml
- Two miles north of Provo Boat Harbor: 218,365 cells/ml
Taxonomy
Multiple cyanobacteria taxa capable of producing toxins are present at different locations in the lake. Aphanizomenon, Dolichospermum, Microcystis, Aphanocapsa, Synechocystis and Lyngbya were present in the Utah Lake samples collected September 5, 2017, particularly Aphanizomenon, Aphanizomenon, Dolichospermum, Microcystis are potential toxin producers for microcystin, anatoxin-a, and cylindrospermopsin. Lyngbya is a potential toxin producer for cylindrospermopsin, anatoxin-a, saxitoxin, and lyngbyatoxin-a, a toxin that can produce acute dermatitis in humans. Synechocystisis and Aphanocapsa are potential toxin producers for microcystin.
Update September 7, 2017
Utah Lake
BYU researchers collected eight samples at Utah Lake on September 5, 2017. Toxin strip-tests detected anatoxin-a and microcystin at various locations on the lake. Toxin test results at all Utah Lake sampling locations were below the health-based warning advisory for microcystin. While toxin strip-test results were at the low end of the warning-advisory threshold for anatoxin-a, any results above non-detect trigger a warning advisory under UDOH and UDEQ health-based guidance.
Jordan River
The Salt Lake County Health Department (SLCHD) collected two samples along the Jordan River on September 5, 2017. Toxin strip tests were non-detect for all toxins with the exception of a low level of anatoxin-a at the Jordan Narrows. Since Blackridge Reservoir is closed for the season, SLCHD has discontinued testing at that location.
ELISA testing on samples taken on August 29, 2017, detected microcystin levels well below the health-based warning advisory.
Warning Advisory for the majority of Utah Lake and Jordan River
A Warning Advisory indicates a moderate relative probability of acute health risk, cell count density of 20,000 -10 million cells per milliliter, 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 drink the water
- Keep pets and livestock away
- Clean fish well and discard guts
- Avoid areas of scum when boating
Sampling Date and Locations
Utah Lake
September 5, 2017
BYU researchers collected eight samples on Utah Lake.
- One mile west of Provo Boat Harbor
- Two miles west of Vineyard
- Two miles east of Bird Island
- Mouth of Provo Bay
- Mouth of Goshen Bay
- 0.5 mile east of Saratoga Marina
- 0.5 mile west of Lindon Marina
- Two miles north of Provo Boat Harbor
Jordan River
September 5, 2017
The Salt Lake County Health Department collected two samples along the Jordan River.
- Jordan Narrows
- Little Cottonwood Creek at Wheeler Farm
August 29, 2017
The Salt Lake County Health Department collected three samples along the Jordan River.
- Jordan Narrows
- Blackridge Reservoir
- Little Cottonwood Creek at Wheeler Farm
Number of Samples
September 5, 2017: eight (Utah Lake)
September 5, 2017: two (Jordan River)
August 29, 2017: three (Jordan River)
Toxins
While toxin strip-test results were at the low end of the warning-advisory threshold for anatoxin-a at sample sites on Utah Lake and the Jordan River, any results above non-detect trigger a warning advisory under UDOH and UDEQ health-based guidance. Toxin test results at all Utah Lake and Jordan River sampling locations were below the health-based warning advisory for microcystin.
Utah Lake
September 5, 2017
Toxin test strips detected low levels of either microcystin and anatoxin-a at over half of the sample sites. No results were available for cylindrospermopsin due to testing errors, but previous strip tests have not detected the cyanotoxin in Utah Lake this year. Samples were non-detect for anatoxin-a and microcystin unless otherwise noted.
- One mile west of Provo Boat Harbor: 0
- Two miles west of Vineyard: 1 microgram per liter (µ/L) anatoxin-a
- Two miles east of Bird Island: 0
- Mouth of Provo Bay: 0.4 µ/L anatoxin-a
- Mouth of Goshen Bay: 1 µ/L microcystin
- 0.5 mile east of Saratoga Marina: 0.4 µ/L anatoxin-a; 1 µ/L microcystin
- 0.5 mile west of Lindon Marina: 1 µ/L anatoxin-a
- Two miles north of Provo Boat Harbor: 0
Jordan River
September 5, 2017
Toxin tests strips were non-detect for all three cyantoxins, with the exception of a very low level of anatoxin-a at the Jordan Narrows.
- Jordan Narrows: >0.4 µ/L anatoxin-a
- Little Cottonwood Creek at Wheeler Farm: 0
August 29, 2017
ELISA testing for microcystins was conducted by the Utah Public Health Lab. Test results were below the UDEQ-UDOH health advisory thresholds for a warning advisory for microcystin.
- Jordan Narrows: 0.53 µ/L microcystin
- Blackridge Reservoir: 0.09 µ/L microcystin
- Little Cottonwood Creek at Wheeler Farm: 0.47 µ/L microcystin
Update September 5, 2017
BYU researchers sent four samples collected on Utah Lake on August 29, 2017, to the lab for cyanobacteria cell-count concentrations and genera identification. Lab results showed that cell-count densities dropped from the previous week’s samples, but remained within the UDEQ-UDOH health advisory thresholds for a warning advisory.
Warning Advisory for the majority of Utah Lake and Jordan River
A Warning Advisory indicates a moderate relative probability of acute health risk, cell count density of 20,000 -10 million cells per milliliter, 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 drink the water
- Keep pets and livestock away
- Clean fish well and discard guts
- Avoid areas of scum when boating
Sampling Date and Locations
August 29, 2017
The following four samples were sent to the lab for cell-count concentrations.
- One mile west of Provo Boat Harbor
- Two miles west of Vineyard
- Mouth of Provo Bay
- 0.5 miles west of Lindon Marina
Toxigenic Cyanobacteria Cell-Count Concentrations
Cell-count concentrations for the August 29, 2017, samples on Utah Lake:
- One mile west of Provo Boat Harbor: 156,502 cells per milliliter (cells/ml)
- Two miles west of Vineyard: 60,492 cells/ml
- Mouth of Provo Bay: 146,476 cells/ml
- 0.5 miles west of Lindon Marina: 72,331 cells/ml
Taxonomy
Multiple cyanobacteria taxa capable of producing toxins are present at different locations in the lake. Aphanizomenon, Dolichospermum, Microcystis, Plankothrix, and Lyngbya were present in the Utah Lake samples collected August 29, 2017, particularly Aphanizomenon and Microcystis. All genera with the exception of Lyngbya are potential toxin producers for microcystin, anatoxin-a, and cylindrospermopsin. Lyngbya is a potential toxin producer for cylindrospermopsin, anatoxin-a, saxitoxin, and lyngbyatoxin-a, a toxin that can produce acute dermatitis in humans.
Update August 30, 2017
BYU researchers collected seven samples at Utah Lake on August 29, 2017. Toxin strip-test results showed low levels of anatoxin-a at four of the seven sites sampled. Strip tests were non-detect for microcystin and cylindrospermopsin at all sample sites.
Samples from the Provo Boat Harbor, Vineyard buoy, and the mouth of Provo Bay were sent to the lab for cyanobacteria cell-count concentrations and genera identification.
Warning Advisory for the majority of Utah Lake and Jordan River
A Warning Advisory indicates a moderate relative probability of acute health risk, cell count density of 20,000 -10 million cells per milliliter, 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 drink the water
- Keep pets and livestock away
- Clean fish well and discard guts
- Avoid areas of scum when boating
Sampling Date and Locations
August 29, 2017
- One mile west of Provo Boat Harbor
- Two miles west of Vineyard
- Two miles east of Bird Island
- Mouth of Provo Bay
- Mouth of Goshen Bay
- 0.5 miles east of Saratoga Marina
- 0.5 miles west of Lindon Marina
Toxins
While toxin strip-test results were at the low end of the warning-advisory threshold for anatoxin-a at four of the seven sample sites, any results above non-detect trigger a warning advisory under UDOH and UDEQ health-based guidance.
August 29, 2017
Toxin strip tests conducted by BYU researchers were non-detect for microcystin and cylindrospermopsin at all test sites. Toxin strip tests were non-detect for all three cyanotoxins at the Bird Island, Saratoga Marina, and Lindon Marina sample sites.
- One mile west of Provo Boat Harbor: 1 microgram per liter (µ/L) of anatoxin-a
- Two miles west of Vineyard: 0.4 µ/L of anatoxin-a
- Two miles east of Bird Island: 0
- Mouth of Provo Bay: 0.4 µ/L of anatoxin-a
- Mouth of Goshen Bay: 0.4 µ/L of anatoxin-a
- 0.5 miles east of Saratoga Marina: 0
- 0.5 miles west of Lindon Marina: 0
Update August 28, 2017
Utah Lake
BYU researchers collected four samples at Utah Lake on August 22, 2017. Cyanobacteria cell-count concentrations showed an increase from the August 16, 2017, samples, but cell-count densities still remain within the UDEQ-UDOH health-advisory guidance for a warning advisory.
Toxin strip-test results showed low levels of anatoxin-a at three of the four sites sampled. Strip tests were non-detect for microcystin and cylindrospermopsin at all sample sites.
Jordan River
The Salt Lake County Health Department (SLCHD) sampled three locations along the Jordan River on August 22, 2017. Toxin test strips detected anatoxin-a and 1.5 micrograms per liter (µg/L) of cylindrospermopsin at the Jordan Narrows, and low levels of microcystin at all three test sites. Enzyme-Linked Immunosorbent Assay (ELISA) toxin testing of these samples by the Utah Public Health Lab confirmed low levels of microcystin at the three sample sites.
Warning Advisory for the majority of Utah Lake and Jordan River
A Warning Advisory indicates a moderate relative probability of acute health risk, cell count density of 20,000 -10 million cells per milliliter, 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 drink the water
- Keep pets and livestock away
- Clean fish well and discard guts
- Avoid areas of scum when boating
Sampling Date and Locations
Utah Lake August 22, 2017
BYU researchers collected four samples at Utah Lake.
- One mile west of Provo Boat Harbor
- Two miles west of Vineyard
- One mile east of Bird Island
- Three miles south of Provo Boat Harbor
Jordan River
August 22, 2017
The Salt Lake County Health Department collected three samples along the Jordan River.
- Jordan River Narrows
- Blackridge Reservoir
- Little Cottonwood Creek at Wheeler Farm
Number of samples
August 22, 2017: four (Utah Lake)
August 22, 2017: three (Jordan River)
Cyanobacteria Cell-Count Concentrations
Cell-count concentrations for the August 22, 2017, samples on Utah Lake
- One mile west of Provo Boat Harbor: 298,242 cells per milliliter (cells/ml)
- Two miles west of Vineyard: 229,208 cells/ml
- One mile east of Bird Island: 26,757 cells/ml
- Three miles south of Provo Boat Harbor: 103,282 cells/ml
Taxonomy
Multiple cyanobacteria taxa capable of producing toxins are present at different locations in the lake. Aphanizomenon, Dolichospermum, Microcystis, and Plankothrix were present in the Utah Lake samples collected August 22, 2017, particularly Aphanizomenon. All genera are potential toxin producers for microcystin, anatoxin-a, and cylindrospermopsin.
Toxins
Toxin test results at all Utah Lake sampling locations were below the health-based warning advisory for microcystin, and cylindrospermopsin. While toxin strip test results for sampling conducted on August 22, 2017, were at the low end of the warning-advisory threshold for anatoxin-a, any results above non-detect trigger a warning advisory under UDOH and UDEQ health-based guidance.
Toxin test strips performed on samples from the Jordan River detected low levels of anatoxin-a and 1.5 micrograms per liter (µg/L) of cylindrospermopsin at the Jordan Narrows, and low levels of microcystin at all three test sites. While toxin strip test results for sampling conducted on August 22, 2017, were at the low end of the warning-advisory threshold for anatoxin-a, any results above non-detect trigger a warning advisory under UDOH and UDEQ health-based guidance. All toxin strip-test results fell below the health-based warning advisory level for cylindrospermopsin and microcystin.
Utah Lake
Toxin strip-test results showed low levels of anatoxin-a at three of the four sites sampled. Strip tests were non-detect for microcystin and cylindrospermopsin at all sample sites.
- One mile west of Provo Boat Harbor: 0.4 micrograms per liter (µg/L)
- Two miles west of Vineyard: 0.4 µg/L
- One mile east of Bird Island: 0
- Three miles south of Provo Boat Harbor: 1 µg/L
Jordan River
ELISA testing for microcystins was conducted by the Utah Public Health Lab.
- Jordan River Narrows: 0.22 µg/L microcystin
- Blackridge Reservoir: 0.14 µg/L microcystin
- Little Cottonwood Creek at Wheeler Farm: 0.22 µg/L microcystin
Update August 23, 2017
BYU researchers collected four samples at Utah Lake on August 22, 2017. Toxin strip-test results showed low levels of anatoxin-a at three of the four sites sampled. Strip tests were non-detect for microcystin and cylindrospermopsin at all sample sites.
Warning Advisory for the majority of Utah Lake and Jordan River
A Warning Advisory indicates a moderate relative probability of acute health risk, cell count density of 20,000 -10 million cells per milliliter, 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 drink the water
- Keep pets and livestock away
- Clean fish well and discard guts
- Avoid areas of scum when boating
Sampling Date and Locations
August 22, 2017
- One mile west of Provo Boat Harbor
- Two miles west of Vineyard
- Two miles east of Bird Island
- Three miles south of Provo Boat Harbor
Toxins
August 22, 2017
Toxin strip tests conducted by BYU researchers were non-detect for microcystin and cylindrospermopsin at all test sites. The Bird Island sample site was non-detect for all three cyanotoxins.
- One mile west of Provo Boat Harbor: 0.4 micrograms per liter (µg/L) anatoxin-a
- Two miles west of Vineyard: 0.4 µg/L anatoxin-a
- Two miles east of Bird Island: non-detect for anatoxin-a
- Three miles south of Provo Boat Harbor: 1 µg/L anatoxin-a
Update August 18, 2017
Utah Lake
Recent sampling results exemplify the tendency for blooms to shift quickly in size, location, and levels/presence of cyanotoxins. Division of Water Quality (DWQ) sampling on August 14, 2017, showed a sharp increase in bloom activity at the American Fork Boat Harbor and the Lindon Marina. Cyanobacteria cell-count concentrations at American Fork Boat Harbor were >5.7 million cells per milliliter (cells/ml), a significant jump from previous sampling. Lindon Marina cell-count concentrations ranged from ∼86,000 cells/ml to ∼126,000 cells/ml depending on the sampling location within the marina. These cyanobacteria cell-count densities are well above the 20,000 cells/ml threshold in the UDEQ-UDOH health advisory guidance for a warning advisory. The >5.7 million cells/ml sample result at American Fork Harbor is the highest cyanobacteria cell-count concentration identified this summer on Utah Lake.
Enzyme-Linked Immunosorbent Assay (ELISA) toxin testing of a Lindon Marina sample by the Utah Public Health Lab found microcystin levels of >5 µg/L, which is above the 4 µg/L warning advisory threshold in UDEQ-UDOH health advisory guidance.
Brigham Young University (BYU) researchers took samples at seven locations across the lake on August 16, 2017. Cyanobacteria cell-count concentration results from these samples should be available on August 21, 2017. Toxin strip tests for these samples detected low levels of anatoxin-a, microcystin, and cylindrospermopsin at various locations on the lake.
Jordan River
The Salt Lake County Health Department (SLCHD) sampled three locations along the Jordan River on August 14, 2017. Toxin strip test results for anatoxin-a, microcystin, and cylindrospermopsin were negative at all three sample sites, with the exception of a 1.5 µg/L strip-test result for cylindrospermopsin at the Jordan Narrows. Subsequent ELISA testing by the Utah Public Health Lab detected very low levels of microcystin at all three sample sites, and all results were well below the health-based warning advisory threshold.
Warning Advisory for the majority of Utah Lake and Jordan River
A Warning Advisory indicates a moderate relative probability of acute health risk, cell count density of 20,000 -10 million cells per milliliter, 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 drink the water
- Keep pets and livestock away
- Clean fish well and discard guts
- Avoid areas of scum when boating
Sampling Date and Locations
August 14, 2017
Division of Water Quality scientists collected one sample at American Fork Harbor and three samples at the Lindon Marina.
- American Fork Boat Harbor
- Lindon Marina beach
- Lindon Marina near boat slips
- Lindon Marina from north dike
August 14, 2017
Salt Lake County Health Department collected three samples along the Jordan River.
- Jordan River Narrows
- Blackridge Reservoir
- Little Cottonwood Creek at Wheeler Farm
August 16, 2017
BYU researchers collected seven samples across the lake.
- One mile west of Provo Boat Harbor
- Two miles west of Vineyard
- One mile east of Bird Island
- Mouth of Provo Bay
- Mouth of Goshen Bay
- One-half mile east of Saratoga Marina
- One-half mile west of Lindon Marina
Number of Samples
- August 14, 2017 (DWQ): four
- August 14, 2017 (SLCHD): three
- August 16, 2017 (BYU): seven
Cyanobacteria Cell-Count Concentrations
August 14, 2017
Cell-count concentrations are for the August 14, 2017, samples on Utah Lake.
- American Fork Boat Harbor: 5,749,682 cells/ml
- Lindon Marina beach: 106,232 cells/ml
- Lindon Marina near boat slips: 86,660 cells/ml
- Lindon Marina from north dike: 126,149 cells/ml
August 16, 2017
Cell -count concentrations are for the August 16, 2017, samples on Utah Lake. Note: Only four of the seven samples were sent to the lab for cell-count densities.
- One-half mile east of Saratoga Marina: 150,897 cells/ml
- Two miles west of Vineyard: 54,122 cells/ml
- One mile west of Provo Marina: 113,833 cells/ml
- One mile east of Bird Island: 72,103 cells/ml
Taxonomy
Multiple cyanobacteria taxa capable of producing toxins are present at different locations in the lake. Aphanizomenon, Dolichospermum, Microcystis, and Plankothrix were present in the Utah Lake samples collected August 14, 2017, in particular Microcystis. All genera are potential toxin producers for microcystin, anatoxin-a, and cylindrospermopsin.
Toxins
One sample taken on August 14, 2017, at the Lindon Marina was above the 4 µg/L threshold for the health-based warning advisory for microcystin. Toxin test results at other sampling locations were below the health-based warning advisory for microcystin, and cylindrospermopsin. While toxin strip test results for sampling conducted on August 16, 2017, were at the low end of the warning-advisory threshold for anatoxin-a, any results above non-detect trigger a warning advisory under UDOH and UDEQ health-based guidance.
Toxin test-strip results showed the presence of cylindrospermopsin, a cyanotoxin that hasn’t been detected previously this year in either the Jordan River or Utah Lake. All toxin strip-test results fell below the health-based warning advisory level for cylindrospermopsin.
Utah Lake
August 14, 2017
Toxin strip tests conducted by DWQ scientists were non-detect for anatoxin-a, but detected microcystin at one location and cylindrospermopsin at another location.
- American Fork Boat Harbor: non-detect for all cyanotoxins
- Lindon Marina beach: non-detect for all cyanotoxins
- Lindon Marina near boat slips: non-detect for anatoxin-a and microcystin; 0.5 µg/L for cylindrospermopsin
- Lindon Marina from north dike: non-detect for anatoxin-a and cylindrospermopsin; 2.5 µg/L for microcystin
ELISA testing conducted by the Utah Public Health Lab showed microcystin levels at Lindon Marina above the 4 µg/L warning advisory threshold in UDEQ-UDOH health advisory guidance.
- American Fork Boat Harbor: 0.93 µg/L microcystin
- Lindon Marina: >5 µg/L microcystin
August 16, 2017
Toxin strip testing was conducted by BYU researchers. Several of the strip test results report as NA, meaning the researchers weren’t able to run the analysis.
- One mile west of Provo Boat Harbor: non-detect for anatoxin-a and microcystin; 0.5 µg/L for cylindropermopsin
- Two miles west of Vineyard: non-detect for microcystin; 0.4 µg/L for anatoxin-a; 0.5 µg/L for cylindrospermopsin
- Two miles east of Bird Island: non-detect for microcystin; 1 µg/L for anatoxin-a; 0.5 µg/L for cylindrospermopsin
- Mouth of Provo Bay: 1 µg/L for anatoxin-a; other cyanotaoxins NA
- Mouth of Goshen Bay: 1 µg/L for anatoxin-a; other cyanotaoxins NA
- One-half mile east of Saratoga Marina: non-detect for microcystin; 0.4 µg/L for anatoxin-a; 0.5 µg/L for cylindrospermopsin
- One-half mile west of Lindon Marina: 1 µg/L for anatoxin-a; other cyanotaoxins NA
Jordan River
August 14, 2017
ELISA testing for microcystins was conducted by the Utah Public Health Lab. Toxin strip tests were also performed for anatoxin-a, microcystin, and cylindrospermopsin. Toxin strip-test results were non-detect for anatoxin-a and cylindrospermopsin unless otherwise noted.
- Jordan River Narrows: 0.47 µg/L microcystin (ELISA test); 1.5 µg/L cylindrospermopsin (toxin strip test)
- Blackridge Reservoir: 0.16 µg/L microcystin (ELISA test)
- Little Cottonwood Creek at Wheeler Farm: 0.45 µg/L microcystin (ELISA test)
Update August 11, 2017
Cyanobacteria cell-count concentrations have increased in some areas of the lake since the July 27, 2017, sampling. While the cell-count densities in nine of the twelve samples collected August 7-8, 2017, fell below the 20,000 cells per milliliter (cells/ml) threshold for a warning advisory, three samples were well above that, with Provo Bay registering the highest at ∼195,000 cells/ml. The Utah County Health Department conducted visual inspections of the lake on August 7, 2017, and took samples for toxins at two locations that showed algal growth — Lincoln Beach and State Park Harbor. UCHD observed a bloom in Lindon Marina on August 11, 2017, but photographic evidence indicates that it was not visible by the afternoon.
Strip tests and Enzyme-Linked Immunosorbent Assay (ELISA) tests by the State Public Health Lab show the continued presence of low levels of cyantoxins in the lake. Five of seven samples collected across the lake on August 3, 2017, detected anatoxin-a. While all but two of the toxin test-strip results for 14 samples taken August 7-8, 2017, were non-detect for anatoxin-a. ELISA testing of the samples by the State Public Health Lab showed the presence of microcystin, with one sample at Pelican Point exceeding the criteria for a warning advisory under Utah Department of Environmental Quality-Utah Department of Health health advisory guidance. The Utah Department of Agriculture and Food (UDAF) lab is running the August 7-8, 2017, samples for anatoxin-a: results are expected early next week.
Sampling by the Salt Lake County Health Department in three Jordan River collection sites were non-detect for anatoxin-a and were below the health advisory threshold for microcystin. The health department has not received any new reports of bloom activity in the Jordan River.
The Utah Poison Control Center (UPCC) continues to handle calls related to the algal bloom on Utah Lake, with 147 calls to date. Adverse effects, including gastrointestinal distress, dizziness, or skin irritation, have been noted in approximately 27 percent of the cases reported.
The warning advisory remains in place.
Warning Advisory for the majority of Utah Lake and Jordan River
A Warning Advisory indicates a moderate relative probability of acute health risk, cell count density of 20,000 -10 million cells per milliliter, 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 drink the water
- Keep pets and livestock away
- Clean fish well and discard guts
- Avoid areas of scum when boating
Sampling Date and Locations
August 3, 2017
Researchers from BYU collected samples at numerous locations across the lake.
- One mile west of State Park Harbor
- Two miles west of Vineyard
- One mile east of Bird Island
- Mouth of Provo Bay
- Mouth of Goshen Bay
- One-half mile east of Saratoga Marina
- One-half mile west of Lindon marina
August 7, 2017
DEQ scientists collected samples at three locations in the lake.
- Goshen Bay southwest end
- Outside entrance to Provo Bay
- Middle of Provo Bay
August 7, 2017
Utah County Health Department collected two shoreline samples.
- Lincoln Beach
- State Park Marina
August 8, 2017
DEQ scientists collected samples at numerous locations across the lake.
- Three miles west-northwest of Lincoln Beach
- One mile northeast of Lincoln Point
- One mile southeast of Bird Island
- One mile west of Provo Marina
- One mile east of Pelican Point
- Two miles east of Saratoga Springs
- One-half mile west of Geneva discharge #15-A (Lindon Harbor)
- Two miles west of Vineyard
- One-half mile west of Geneva discharge #15-B (Lindon Harbor)
August 8, 2017
Salt Lake County Health Department collected three samples along the Jordan River.
- Blackridge Reservoir
- Jordan River Narrows
- Little Cottonwood Creek at Wheeler Farm
Number of Samples
- August 3, 2017 (BYU): seven
- August 7, 2017 (DEQ): three
- August 7, 2017 (UCHD): two
- August 8, 2017 (DEQ): nine
- August 8, 2017 (SLCHD): three
Toxigenic Cyanobacteria Cell-Count Concentrations
August 7, 2017
- Goshen Bay southwest end: 63,390 cells per milliliter (cells/ml)
- State Park Marina: 2,541 cells/ml
- Middle of Provo Bay: 195,177 cells/ml
- Outside entrance to Provo Bay: 0 cells/ml
- Lincoln Beach: 0 cells/ml
August 8, 2017
- Three miles west-northwest of Lincoln Beach (mouth of Goshen Bay): 3,541 cells/ml
- One mile northeast of Lincoln Point: 8,799 cells/ml
- One mile southeast of Bird Island: 381 cells/ml
- One mile west of Provo Marina: 6,359 cells/ml
- One mile east of Pelican Point: 8,385 cells/ml
- Two miles east of Saratoga Springs: 10,068 cells/ml
- One-half mile west of Geneva discharge #15-A (Lindon Harbor): 5,420 cells/ml
- Two miles west of Vineyard: 58,021 cells/ml
- One-half mile west of Geneva discharge #15-B (Lindon Harbor): 1,186 cells/ml
Taxonomy
Multiple cyanobacteria taxa capable of producing toxins are present at different locations in the lake. Aphanizomenon, Dolichospermum, Microcystis, Lyngbya,and Plankothrix were present in the samples. All genera are potential toxin producers for microcystin and anatoxin-a.
Toxins
Toxin test-strip results from samples collected August 3, 2017, show the continued presence of very low levels of anatoxin-a across the lake. While toxin test strips from the August 8, 2017, samples came back as non-detect for microcystin, Enzyme-Linked Immunosorbent Assay (ELISA) testing of the samples by the State Public Health Lab showed the presence of microcystin, with one sample at Pelican Point exceeding the criteria for a warning advisory under Utah Department of Environmental Quality – Utah Department of Health health advisory guidance.
August 3, 2017
Non-detect for anatoxin-a, microcystin, and cylindrospermopsin unless otherwise noted
- One mile west of State Park Harbor
- Two miles west of Vineyard: 0.4 µg/L for anatoxin-a
- One mile east of Bird Island: 0.4 µg/L for anatoxin-a
- Mouth of Provo Bay: 0.4 µg/L for anatoxin-a
- Mouth of Goshen Bay: 0.4 µg/L for anatoxin-a
- One-half mile east of Saratoga Marina: 0.4 µg/L for anatoxin-a
- One-half mile west of Lindon marina
August 7, 2017
Non-detect for anatoxin-a, microcystin, and cylindrospermopsin unless otherwise noted
- Goshen Bay southwest end: <1 µg/L microcystin
- Outside entrance to Provo Bay: <1 µg/L microcystin
- Middle of Provo Bay: <0.4 µg/L for anatoxin-a, >1 µg/L microcystin
August 7, 2017
Non-detect for anatoxin-a, microcystin, and cylindrospermopsin
- Lincoln Beach
- State Park Marina
August 8, 2017
Non-detect for anatoxin-a, microcystin, and cylindrospermopsin unless otherwise noted
- Three miles west-northwest of Lincoln Beach: <1 µg/L microcystin
- One mile northeast of Lincoln Point: <1 µg/L microcystin
- One mile southeast of Bird Island: <0.4 µg/L for anatoxin-a; <1 µg/L microcystin
- One mile west of Provo Marina: <1 µg/L microcystin
- One mile east of Pelican Point: 4.38 µg/L microcystin
- Two miles east of Saratoga Springs: <1 µg/L microcystin
- One-half mile west of Geneva discharge #15-A: >1 µg/L microcystin
- Two miles west of Vineyard: >1 µg/L microcystin
- One-half mile west of Geneva discharge #15-B: >1 µg/L microcystin
August 8, 2017
Non-detect for anatoxin-a, microcystin, and cylindrospermopsin unless otherwise noted
- Blackridge Reservoir: <1 µg/L microcystin
- Jordan River Narrows: <1 µg/L microcystin
- Little Cottonwood Creek at Wheeler Farm: <1 µg/L microcystin
Update August 2, 2017
A series of storms last week appears to have dispersed the lake’s algal bloom. Cyanobacteria cell-counts on Utah Lake dropped dramatically, with counts coming in well below the 20,000 cells per milliliter (cells/ml) threshold for a warning advisory. Toxin test-strip results from the Utah Lake buoys and the Jordan River detected very low levels of anatoxin-a, and were non-detect for microcystins and cylindrospermopsin.
According to UDEQ-UDOH health advisory guidance, an advisory may be rescinded after two consecutive weeks of sampling data indicate the hazard has passed.
BYU researchers will collect samples at approximately eight locations across the lake on August 3, 2017, and Utah County Health scientists will collect shoreline samples for toxin testing on August 7, 2017. Results from sampling later this week and early next week will help the Utah County Health Department determine whether current conditions warrant lifting the warning advisory for the majority of Utah Lake, adjusting the advisory to include specific areas of the lake only, or retaining the advisory.
Warning Advisory for the majority of Utah Lake and the Jordan River
A Warning Advisory indicates a moderate relative probability of acute health risk, cell count density of 20,000 -10 million cells per milliliter, 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 drink the water
- Keep pets and livestock away
- Clean fish well and discard guts
- Avoid areas of scum when boating
Sampling date and locations
July 25, 2017
Salt Lake County Health Department staff collected samples from the Jordan River complex.
- Jordan River at Wheeler farm
- Jordan Narrows
- Blackridge Reservoir
July 27, 2017
Researchers from BYU collected samples at the three buoys and one additional location.
- Two miles west of Vineyard
- One mile west of Provo Harbor
- Two miles east of Bird Island
- One-half mile northwest of State Harbor
Number of samples
- July 25, 2017: three
- July 27, 2017: four
Cell-count concentrations
- Two miles west of Vineyard: 4,984 cells per milliliter (cells/ml)
- One mile west of Provo Harbor: 67 cells/ml
- Two miles east of Bird Island: 67 cells/ml
- One-half mile northwest of State Harbor: 627 cells/ml
Taxonomy
Multiple cyanobacteria taxa capable of producing toxins are present at different locations in the lake. Aphanizomenon, Dolichospermum, and Microcystis were present in the samples. All genera are potential toxin producers for microcystin and anatoxin-a.
Toxins
While three of the four toxin test strips run for the July 27, 2107, samples from Utah Lake detected anatoxin-a, Enzyme-Linked Immunosorbent Assay (ELISA) testing of these same samples by the Environmental Protection Agency (EPA) Region 8 Lab in Golden, Colorado, were non-detect for anatoxin-a. DWQ plans to work with test-strip manufacturers, the EPA lab, and others in the scientific community to identify the possible cause(s) of these discrepancies. Anatoxin-a testing is still relatively new, and further work may be required to ensure consistent results.
Update July 25, 2017
Jordan River
Test results received on July 21, 2017, by the Salt Lake County Health Department showed a low level of anatoxin-a in the Jordan River at the Jordan Narrows. These 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.
Salt Lake County health officials advised people to not swim in the water and keep dogs from swimming in or drinking river water. Although the samples showing low-levels of the toxin were taken from the Jordan Narrows, officials were advising caution for the entire river since toxins can spread and levels can change quickly.
The Salt Lake County Health Department posted warning signs at Wheeler Farm in Murray and Blackridge Reservoir. Herriman City closed Blackridge Reservoir on July 21, 2017, based on the health department’s warning advisory. The reservoir will remain closed pending further test results.
Salt Lake County health officials will continue to monitor and sample the Jordan River and its related canals and will update advisories as necessary.
Utah Lake
Samples taken from four locations on Utah Lake on July 18, 2017, had cell-count concentrations over 100,000 cells per milliliter (cells/ml), with cell-count densities at the State Park sample site exceeding 620,000 cells/ml. Toxin test strips were used for two of the samples; results for both samples were non-detect for microcystin and very low-levels for anatoxin-a.
Warning Advisory for the majority of Utah Lake and the Jordan River
A Warning Advisory indicates a moderate relative probability of acute health risk, cell count density of 20,000 -10 million cells per milliliter, 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 drink the water
- Keep pets and livestock away
- Clean fish well and discard guts
- Avoid areas of scum when boating
Sampling date and locations
July 17, 2017:
Samples collected on the Jordan River by Salt Lake County Health Department.
- Jordan River Narrows
- Jordan River at Wheeler Farm
July 18, 2017:
Samples collected on Utah Lake by BYU researchers.
- Two miles west of Vineyard
- One mile west of Provo Boat Harbor
- One mile east of Bird Island
- One-half mile northwest of State Park
Number of samples
July 17, 2017: two
July 18, 2017: four
Cell-count concentrations
Cell-count concentrations posted here are for the July 18, 2017, samples from Utah Lake.
- Two miles west of Vineyard: 149,093 cells per milliliter (cells/ml)
- One mile west of Provo Boat Harbor: 191,474 cells/ml
- One mile east of Bird Island: 122,004 cells/ml
- One-half mile northwest of State Park: 620,227 cells/ml
Taxonomy
Multiple cyanobacteria taxa capable of producing toxins are present at different locations in the lake. Aphanizomenon was the dominant genera at all sample sites. Dolichospermum was present in all samples, but at lower levels. Both are typically high-toxin producers for microcystin and anatoxin-a. Other taxa present in the most recent samples include Microcystis.
Toxins
Jordan River
Samples taken at the Jordan Narrows and Wheeler Farm showed very low levels of microcystin and a low level (?0.1 micrograms per liter (µg/L) of anatoxin-a. Any results above non-detect for anatoxin-a trigger a warning advisory under UDOH and DEQ health-based guidance. Microcystin levels were well below the 4-2,000 micrograms per liter (µg/L) threshold for both samples.
Utah Lake
Toxin test strips were conducted on two of the four samples collected from Utah Lake on July 18, 2017.
- One mile west of Provo Marina
- Non-detect for microcystin
- 0.4 µg/L for anatoxin-a
- One-half mile northwest of State Harbor
- Non-detect for microcystin
- 0.4 µg/L for anatoxin-a
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 cells per milliliter, 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 cells per milliliter, 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.
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 cells per milliliter 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.
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 cells per milliliter, microcystins 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
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.
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 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 cells per milliliter, microcystins levels of 4-2,000 micrograms per liter (ug/L), or anatoxin-a levels above non-detect. Advisory actions.
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
- 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
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.