Upper Box Creek Reservoir Algal Bloom Monitoring 2019

Warning Advisory

  • Do not swim or water ski in this area.
  • Avoid areas of algae scum when boating.
  • Keep animals away.
  • Do not ingest the water.
  • Clean fish well and discard guts.

Report a Bloom

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

Call Utah Poison Control Center

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

Visit the 2019 Photo Gallery

Get BloomWatch App

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

Update August 28, 2019

Upper Box Creek Reservoir, August 15, 2019

The Division of Water Quality (DWQ) received toxin test results from the Utah Public Health Lab (UPHL) on August 27, 2019, for samples collected August 15, 2019, at the midway shore of Upper Box Creek Reservoir. Microcystin concentrations were well below the recreation health-based threshold for a Warning Advisory, but anatoxin-a was detected in the water column sample. Cyanobacteria cell-count concentrations are still pending from PhycoTech.

The DWQ monitoring crew observed small particulates in the reservoir, and the water column had a green hue. Cyanobacteria resembling grass clippings were concentrated in the water column. These cyanobacteria were persistent throughout the waterbody and formed concentrated clumps in some areas.

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.

Due to the detection of anatoxin-a, the Warning Advisory for Upper Box Creek Reservoir remains in place.

Surface sample

  • Sample Date: August 15, 2019
  • Microcystin: <0.10 micrograms per liter (µg/L)
  • Anatoxin-a: <0.10 µg/L

Elbow-depth integrated composite sample

  • Sample Date: August 15, 2019
  • Microcystin: <0.10 micrograms per liter (µg/L)
  • Anatoxin-a: 0.13 µg/L

Update August 14, 2019

Upper Box Creek Reservoir

Upper Box Creek Reservoir, August 9, 2019

Cyanobacteria cell-count concentrations from samples collected by the Division of Water Quality (DWQ) at the midway shore of Upper Box Creek Reservoir on August 9, 2019, were above the recreation health-based threshold for a Warning Advisory. Cell counts had dropped from the previous week but remained above the health advisory threshold.  Aphanizomenon was the primary taxon in both samples.

Toxin test results from the Utah Public Health Lab for anatoxin-a and microcystin were well below recreation health-based thresholds for a health advisory.

The DWQ monitoring crew observed greenish-yellow cyanobacteria throughout the reservoir. These cyanobacteria were also visible throughout the water column. The crew observed consistent concentrations cyanobacteria resembling grass clippings and dispersed spherical nodules. A green hue to the reservoir was visible from the road.

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.

Upper Box Creek Reservoir remains under a Warning Advisory.

Data Summary

Surface sample

  • Sample Date: August 9, 2019
  • Microcystin: 0.106 micrograms per liter (µg/L)
  • Anatoxin-a: <0.10 µg/L
  • Cell Counts: 731,451 cells per milliliter (cells/mL)

Elbow-depth integrated composite sample

  • Sample Date: August 9, 2019
  • Microcystin: <0.10 micrograms per liter (µg/L)
  • Anatoxin-a: <0.10 µg/L
  • Cell Counts: 105,017 cells per milliliter (cells/mL)

Update August 12, 2019

Upper Box Creek

Upper Box Creek Reservoir, August 1, 2019

The Division of Water Quality (DWQ) received cyanobacteria cell-count concentrations from samples collected at Upper Box Creek Reservoir on August 1, 2019. Cell counts increased over the previous week’s sample results, approaching 1.2 million cells per milliliter (cells/mL) in the surface sample. Cyanobacteria species were almost evenly split between Aphanizomenon and Dolichospermum in the water column sample, but Aphanizomenon was the primary taxon in the surface sample.

Toxin test results from the Utah Public Health Lab showed an increase in anatoxin-a levels in the surface sample over the previous week’s results, moving from non-detect to detect. Microcystin levels remained well below the recreation health-based threshold in both sample types.

The DWQ monitoring crew observed visible cyanobacteria that resembled grass clippings concentrated into clumps in some areas of the reservoir. They also observed dispersed nodules of a cylindrical type of cyanobacteria concentrated into streaks on the surface. Clumps of cyanobacteria that resembled grass clippings were dispersed throughout the reservoir. Cyanobacteria were highly concentrated on the surface but present in the water column as well.

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.

Upper Box Creek Reservoir remains under a Warning Advisory.

Data Summary

Surface sample

  • Sample Date: August 1, 2019
  • Microcystin: 0.12 micrograms per liter (µg/L)
  • Anatoxin-a: 0.32 µg/L
  • Cell Counts: 1,172,786 cells per milliliter (cells/mL)

Elbow-depth integrated composite sample

  • Sample Date: August 1, 2019
  • Microcystin: <0.10 micrograms per liter (µg/L)
  • Anatoxin-a: <0.10 µg/L
  • Cell Counts: 283,991 cells per milliliter (cells/mL)

Update August 5, 2019

Upper Box Creek Reservoir, July 26, 2019

Upper Box Creek Reservoir, July 26, 2019

Cyanobacteria cell-counts from samples collected on July 26, 2019, at the midway shore of Upper Box Creek Reservoir were above the recreation health-based threshold for a Warning Advisory. Toxin test results from the Utah Public Health Lab (UPHL) were detect for anatoxin-a and non-detect for microcystin. Any detection of anatoxin-a is above the recreation health-based threshold for a Warning Advisory. Aphanizomenon was the primary taxon in the surface sample, while Dolichospermum was the primary taxon in the water-column sample.

The Division of Water Quality (DWQ) monitoring crew observed visible cyanobacteria that resembled grass clippings, some concentrated into clumps and others concentrated as streaks along the surface. The cyanobacteria were highly concentrated on the surface but also present in the water column.

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.

Upper Box Creek Reservoir remains under a Warning Advisory.

Surface sample

  • Sample Date: July 26, 2019
  • Microcystin: <0.10 micrograms per liter (µg/L)
  • Anatoxin-a: 0.169 µg/L
  • Cell Counts: 901,374 cells per milliliter (cells/mL)

Elbow-depth integrated composite sample

  • Sample Date: July 26, 2019
  • Microcystin: <0.10 micrograms per liter (µg/L)
  • Anatoxin-a: <0.10 µg/L
  • Cell Counts: 101,340 cells per milliliter (cells/mL)

Update July 25, 2019

Upper Box Creek, July 18, 2019

Upper Box Creek, July 18, 2019

The Division of Water Quality (DWQ) collected both surface and elbow-depth integrated water samples at Upper Box Creek Reservoir on July 18, 2019. The monitoring crew observed isolated clumps of cyanobacteria resembling grass clippings on the surface of the water.

DWQ received cyanobacterial cell-count concentration results from PhycoTech on July 24, 2019, of 337,005 cells per milliliter (cells/mL) on the surface and 39,359 cells/mL in the water column. These cell-count densities exceed the recreation health-based threshold for a Warning Advisory. Based on these data, the Central Utah Public Health Department (CUPHD) has issued a Warning Advisory for Upper Box Creek Reservoir.

The CUPHD will be posting signs at the reservoir. The DWQ monitoring crew will collect follow-up samples this week.

Toxin samples were delivered to the Utah Public Health Lab (UPHL) for further analysis. UPHL testing showed anatoxin-a levels of <0.10 micrograms per liter (µg/L) on the surface and within the water column and microcystin levels of 0.15 µg/mL on the surface and <0.10 µg/mL in the water column, all of which are well below the recreation health-based threshold for a Warning Advisory.

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.