Mona Reservoir is located in Mona City at the north end of Juab Valley (Juab County). DEQ’s recreational water quality monitoring checks for two health concerns: Harmful Algal Blooms (HABs) and Waterborne Pathogens (E. coli). Find the most recent monitoring information below.
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Updates
November 1, 2025: Recreational water quality monitoring update
Recreational water quality monitoring has ended for the season. Monitoring will resume in June or July 2026. Harmful algal blooms can occur year-round, so know what to look for and always check before recreating.
October 7, 2025: Waterborne pathogen (E. coli) monitoring update
GOOD NEWS: E. coli counts were measured below recreational thresholds. Sampling suggests that the water is safe from harmful bacteria and viruses.
Site sampled: South of boat ramp
September 8, 2025: Waterborne pathogen (E. coli) monitoring update
GOOD NEWS: E. coli counts were measured below recreational thresholds. Sampling suggests that the water is safe from harmful bacteria and viruses.
Site sampled: South of boat ramp
July 8, 2025: Waterborne pathogen (E. coli) monitoring update
GOOD NEWS: E. coli counts were measured below recreational thresholds. Sampling suggests that the water is safe from harmful bacteria and viruses.
Site sampled: South of boat ramp
June 3, 2025: Waterborne pathogen (E. coli) monitoring update
GOOD NEWS: E. coli counts were measured below recreational thresholds. Sampling suggests that the water is safe from harmful bacteria and viruses.
Site sampled: South of boat ramp
May 12, 2025: Waterborne pathogen (E. coli) and HAB monitoring update
GOOD NEWS: E. coli counts were measured below recreational thresholds and our monitoring team did not see any visible signs of a harmful algal bloom.
Site sampled: south of the boat ramp, SE of the dam.