Rockport Reservoir Algal Bloom Monitoring 2019

Highland Picnic Area: Warning

Warning Advisory
Harmful Algae Present
in Some Areas of Waterbody

  • Do not swim or water ski in areas of algae scum
  • 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.

Get BloomWatch App

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

Update October 18, 2019

Rockport Reservoir, October 16, 2019

Cyanobacteria cell-count concentrations for surface samples collected by the Division of Water Quality (DWQ) on October 16, 2019, at the Highland Picnic Area at Rockport Reservoir continued to exceed the recreation health-based threshold for a Warning Advisory. The primary taxons in the samples were Aphanizomenon and Dolichospermum.

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.

The current Warning Advisory for Rockport Reservoir remains in place.

Data Summary

Highland Picnic Area

  • Sample date: October 16, 2019
  • Sample type: Surface sample
  • Cyanobacteria cell counts: 4,478,519 cells per milliliter (cells/mL)

Highland Picnic Area

  • Sample date: October 16, 2019
  • Sample type: Elbow-depth integrated composite sample
  • Cyanobacteria cell counts: 12,811 cells per milliliter (cells/mL)

Rockport Reservoir, October 2, 2019

Rockport Reservoir, October 2, 2019

Update October 11, 2019

Cyanobacteria cell-count concentrations for samples collected by the Division of Water Quality (DWQ) in the open water at Rockport Reservoir on October 7, 2019, exceeded the recreation health-based threshold for a Warning Advisory. Toxin test results for microcystin and anatoxin-a were well below the advisory threshold.

The DWQ monitoring crew observed large amounts of cyanobacteria that resembled green grass clippings as well as spherical nodules of cyanobacteria particles in the water. Some of the cyanobacteria resembling grass clippings were clumped together.

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.

The current Warning Advisory for Rockport Reservoir remains in place.

Data Summary

Open Water

  • Sample date: October 7, 2019
  • Sample type: Elbow-depth integrated composite sample
  • Microcystin: 0.11 micrograms per liter (µg/L)
  • Anatoxin-a: <0.10 µg/L
  • Cyanobacteria cell counts: 37,495 cells per milliliter (cells/mL)

Update September 13, 2019

Rockport Reservoir, September 13, 2019

Rockport Reservoir, September 13, 2019

The Summit County Health Department (SCHD) posted Warning Advisory signs at the Highland Picnic Area on Rockport Reservoir on September 13, 2019, to alert the public that the area is experiencing a harmful algal bloom.

Rockport Reservoir remains open for recreation at this time. Recreationists are advised to not swim or waterski in areas of scum, avoid boating in areas of scum, keep animals away, and not ingest water. Visitors can still recreate in the reservoir but are cautioned to be mindful of water conditions, as blooms may move or disperse depending on temperature, wind, and weather.

Cyanobacteria cell-count concentrations for samples collected at the Highland Picnic Area at Rockport Reservoir by the Division of Water Quality (DWQ) on September 10, 2019, exceeded the recreation health-based threshold for a Warning Advisory. Toxin test results were non-detect for microcystin and anatoxin-a.

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.

Data Summary

Surface sample

  • Sample date: September 10, 2019
  • Microcystin: <2.0 micrograms per liter (µg/L)
  • Anatoxin-a: <0.10 µg/L
  • Cyanobacteria cell counts: 219,975 cells per milliliter (cells/mL)

Elbow-depth integrated composite sample

  • Sample date: September 10, 2019
  • Microcystin: < 2.0 micrograms per liter (µg/L)
  • Anatoxin-a: <0.10 µg/L
  • Cyanobacteria cell counts: 1,918 cells per milliliter (cells/mL)