Division of Water Quality
Sand Hollow Reservoir Recreational Monitoring
Sand Hollow Reservoir is located approximately 9 miles west of Hurricane in Washington 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.
Check First
Harmful algae mats may be present
- Do not touch or eat algae mats
- Keep dogs and young children away from mats
- Wading and paddling are ok
Updates
September 25, 2026: Harmful algae mats monitoring update
CHECK FIRST: A small number of harmful algae mats were reported at Sand Hollow Reservoir earlier this summer. Direct contact with or ingestion of mats can make humans and animals sick. Avoid mats while you recreate.
- Do not touch or eat any algae mats
- Keep children away from any algae mats
- Keep animals away from any algae mats
- Wading, fishing, and paddling are OK
- Know how to recognize a harmful algae mats
August 7, 2026: Harmful algae mats monitoring update
BE CAREFUL: Harmful algae mats are present at Sand Hollow Reservoir. Direct contact with or ingestion of mats can make humans sick and may be lethal for dogs.
If you visit the reservoir:
- Keep dogs and young children away from the water
- Do not touch or eat any algae mats
- Don't filter drinking water here
- Wading, paddling, and fishing are OK
- Know how to recognize a harmful algae mats
July 21, 2026: 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(s) sampled: Day use beach, Boat Ramp
June 22, 2026: 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(s) sampled: Day use beach, Boat Ramp
May 26, 2026: 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(s) sampled: Day use beach, Boat Ramp