High levels of harmful algal blooms trigger health advisories on Deer Creek, Jordanelle Reservoirs

Island beach and Deer Creek Island Resort plus Island Aqua park. Photo: Utah Department of Natural Resources – State Parks

SUMMIT & WASATCH COUNTIES, Utah – As of Monday September 11, areas on both Jordanelle and Deer Creek reservoirs, along with 25 other waterbodies throughout the state, are under health advisories by the Utah Department of Environmental Quality (DEQ) for high levels of harmful algal blooms or waterborne pathogens.

Charleston day use area on the Deer Creek Reservoir is the only area in the state under a danger advisory by the DEQ, and Rock Cliff boat ramp on the Jordanelle Reservoir, along with four other waterbodies, are all under a health watch advisory.

According to the DEQ, the Charleston Day Use area on the Deer Creek reservoir is exhibiting a harmful algal bloom. The algae in the water is producing high levels of dangerous toxins, and accidentally drinking the water may hurt or kill humans and animals. Any exposure to this water may cause illness.

The DEQ is urging people to not swim or water ski near the Charleston day use area, while the rest of the Deer Creek Reservoir is under a health watch advisory.

Use caution when boating in the reservoir and avoid Charleston day use area and large amounts of algae, do not drink any of the water, eat any fish caught in the reservoir, and keep pets out of the water.

The Rock Cliff boat ramp on the Jordanelle Reservoir was also observed to have a harmful algal bloom by the DEQ. The DEQ is advising to avoid swimming near the Rock Cliff area, clean fish well that are caught in the area and discard the guts, keep pets out of the water, and do not drink the water.

All other areas on the Jordanelle are not under an advisory, but exhibit caution when boating or recreating on the reservoir.

There are three different levels of advisories issued by the DEQ: health watch, warning advisory, and danger advisory.

A health watch is the least severe, and usually means there is evidence that either waterborne pathogens are present or a harmful algal bloom is developing.

A warning advisory usually means a threshold established by the Utah Department of Health and Human Services has been exceeded by the water body. This is a strong indication that either waterborne pathogens or a harmful algal bloom is present.

A danger advisory denotes that the amount of toxic algal blooms in the water body has surpassed the limit set by the Utah Department of Health and Human Services. This indicates that the bloom has grown significantly and/or that dangerously high amounts of toxins have been detected. Frequently, the danger advisory includes a temporary closure of a body of water.

In total, 27 different waterbodies throughout the state have been placed under an advisory. The Charleston day use area on the Deer Creek reservoir is the only waterbody to receive a danger advisory, the Rock Cliff boat ramp on the Jordanelle and four other waterbodies are under a health watch advisory, and 21 waterbodies are under warning advisories.

To see the map of all waterbodies under an advisory and to learn more, visit the DEQ’s webpage.