Starvation Reservoir Algal Bloom Monitoring 2019

Update November 14, 2019

The Tri-County Health Department has removed the Warning Advisory for Starvation Reservoir.

The HABs monitoring season ended on October 31, 2019. The Utah Department of Health and local health departments have determined that the health risk from HABs from primary contact recreation drops with the onset of colder temperatures.

The close of the monitoring season and removal of advisories doesn’t mean HABs are no longer present. HABs can persist throughout the fall and winter and can pose a potential threat to humans and pets. It’s important to recognize the signs of a bloom and take appropriate precautions. Recreators are advised to stay out of the water and avoid any contact with water or scum if they suspect a harmful algal bloom. Hunters and fishers should clean waterfowl and fish well and discard all guts.

Update October 30, 2019

Toxin test results received from the Utah Public Health Lab (UPHL) for samples collected by the Division of Water Quality (DWQ) at the Day Use area at Starvation Reservoir on October 14, 2019, showed anatoxin-a and microcystin levels well below the recreation health-based threshold for a Warning Advisory. Cyanobacteria cell-count concentration results are pending from PhycoTech.

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.

Starvation Reservoir remains under a Warning Advisory.

Data Summary

• Sample date: October 14, 2019
• Sample type: Elbow-depth integrated composite sample
• Microcystin: <2.0 micrograms per liter (µg/L)
• Anatoxin-a: <0.10 µg/L

Update October 11, 2019

Tri-County Health Department (TCHD) issued a Warning Advisory for Starvation Reservoir on October 11, 2019, after cyanobacteria cell-count concentrations from surface samples collected by the Division of Water Quality on October 1, 2019, at the Day Use Area exceeded the recreation health-based advisory threshold for a Warning Advisory. Toxin test results for microcystin and anatoxin-a were well below the advisory threshold. Satellite imagery indicates a bloom in multiple areas of the reservoir. Signs will be posted in the Day Use Area.

The DWQ monitoring crew observed cyanobacteria resembling grass clippings that were well-dispersed throughout the water column. The cyanobacteria were clumped together on the surface in some places. There was also a dusting on cyanobacteria on the surface. The water had a green hue, and the crew observed cyanobacteria at all locations.

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

Day Use Area

• Sample date: October 1, 2019
• Sample type: Surface sample
• Microcystin: <2.0 micrograms per liter (µg/L)
• Anatoxin-a: <0.10 µg/L
• Cyanobacteria cell counts: 181,872 cells per milliliter (cells/mL)

Day Use Area

• Sample date: October 1, 2019
• Sample type: Elbow-depth integrated composite sample
• Microcystin: <2.0 micrograms per liter (µg/L)
• Anatoxin-a: <0.10 µg/L
• Cyanobacteria cell counts: 5,430 cells per milliliter (cells/mL)

Update September 13, 2019

Test results for samples collected by the Division of Water Quality (DWQ) at the Indian Bay Day Use Area at Starvation Reservoir on September 4, 2019, showed a dramatic improvement in bloom conditions. Cyanobacteria cell counts and toxin test results were well below the recreation health-based thresholds for a Warning Advisory.

The Division of Water Quality (DWQ) monitoring crew observed small-particulate cyanobacteria resembling grass clippings in the water column. The water had a green hue.

Tri-County Health has removed the caution signs. Visitors are cautioned to be mindful of water conditions, as blooms may move or disperse depending on temperature, wind, and weather.

Data Summary

• Sample Type: Elbow-depth integrated composite sample
• Sample Date: September 4, 2019
• Microcystin: 2.5 micrograms per liter (µg/L)
• Anatoxin-a: Inconclusive
• Cell Counts: 2,228 cells per milliliter (cells/mL)

Update August 30, 2019

On August 30, 2019, the Division of Water Quality (DWQ) received a report from Utah State Parks about a cyanobacterial bloom at Starvation Reservoir. The bloom appeared overnight and was observed at the dock and a play area. Boaters have also reported seeing the bloom in open water. Samples will be collected and delivered to the lab for toxin testing and cyanobacteria cell-count concentrations. The Tri-County Health Department has posted caution signs to alert the public of the presence of cyanobacteria in the reservoir

Starvation Reservoir remains open for recreation. It’s recommended that recreationists not swim or water ski in areas of scum, avoid boating in areas of scum, not ingest untreated water, and keep animals away from the water. Visitors are cautioned to be mindful of water conditions, as blooms may move or disperse depending on temperature, wind, and weather.