Swimming beach water quality
Dakota County monitors water quality at two public swimming beaches during the summer:
From Memorial Day weekend through Labor Day, water is tested weekly for E. coli levels. This helps protect public health and minimize the risk of recreational water illnesses. Results are typically posted on Wednesdays or Thursdays. Water conditions can change quickly due to rainfall, wildlife or swimmer activity, and temperature. Results reflect conditions at the time of sampling.
Current beach status
Status: Open
Last tested: June 23, 2026
E. coli level (single sample): 1.0 CFU/100 ml
E. coli level (geometric mean): 5.8 CFU/100 ml
Status: Open
Last tested: June 23, 2026
E. coli level (single sample): 5.2 CFU/100 ml
E. coli level (geometric mean): 9.9 CFU/100 ml
What the numbers mean
Dakota County uses EPA and Minnesota standards for E. coli in recreational waters:
- 235 CFU/100 mL—Single sample threshold
- 126 CFU/100 mL—Monthly geometric mean standard
A geometric mean is a monthly average used to check that water quality stays safe over time. If results exceed recommended standards, a follow-up sample is collected. Public Health then reviews the results, and a beach advisory or closure may be issued if necessary. CFU (Colony Forming Units) measures the number of bacteria in 100 milliliters of water.
How we monitor
Each week, county staff collect water samples that are tested for E. coli bacteria. We use Minnesota and Environmental Protection Agency (EPA) recreational water quality standards to guide monitoring and safety decisions.
Staff also conduct weekly visual inspections for harmful algal blooms (blue-green algae).
If levels exceed recommended standards for E. coli, additional testing is conducted. A beach advisory or closure may be issued.
Beach advisory vs. closure
- Beach advisory
- Alerts visitors to potentially unsafe water conditions.
- Swimming is not recommended.
- Visitors may choose to enter the water at their own risk.
- Advisories may be issued for elevated E. coli levels, harmful algal blooms, pollution events or waterborne illness reports.
- Beach closure
- Water conditions have been confirmed to be unsafe.
- Swimming is not permitted until water quality returns to safe levels.
- Beach remains closed until follow-up testing confirms water quality has returned to safe levels.
How Dakota County makes decisions
Environmental Resources, Parks and Public Health staff work together to review results and determine appropriate actions. Public Health staff make the final determination on advisories and closures. Beach status updates will be posted on this webpage and with signage at the beach.
Report a suspected waterborne illness
If you believe you became ill after swimming, contact the Minnesota Department of Health at 1-877-FOOD-ILL (1-877-366-3455). Reports can also be submitted through an online complaint survey.
Swimming pools
MDH reviews and approves new public pool construction plans and licenses and inspects all public pools in Dakota County. If you have a pool complaint, contact MDH at 651-201-4500.
How to drain pools and hot tubs
- Stop adding chlorine at least 3-4 days before draining your pool or hot tub. This allows the chemical to breakdown naturally and dissipate.
- Do not drain pool or hot tub water into storm drains, storm sewers, septic systems, ditches, lakes, wetlands, or surface waters. This is known as an illicit discharge and is
prohibited.
- Direct dechlorinated water onto a lawn or landscaped area where it can soak in and filter naturally through the soil. Drain slowly to reduce erosion and maximize infiltration.
Learn more about best management practices for draining swimming pools and hot tubs.