Tempe Town Lake Safe for Swim Events
May 13, 2011 · Published By Associate Editor
Tempe Town Lake hosts several triathlons each year, with thousands of elite and novice athletes swimming in its waters. The City of Tempe is diligent in testing and treating the water in Tempe Town Lake to make sure it meets water quality standards and is safe for the participants in these events.
“The City of Tempe has no intention of discontinuing swim events in Town Lake,” Assistant City Manager Jeff Kulaga said. “We will continue to host swim events and ensure safe swimming conditions for the athletes through proper testing of the water and, if necessary, treatment.”
Tempe works closely with the Arizona Department of Environmental Quality and Maricopa County – the agencies charged with regulating water bodies – to make sure Town Lake complies with water quality regulations. ADEQ is responsible for setting water quality standards and regulating discharges into a water body, while the county is responsible for regulating the activity that takes place in a water body. Maricopa County Health Code requires that lakes meet state water quality standards during swimming events.
“Swim events will only be held when standards are met,” Kulaga said.
The water in Town Lake is tested weekly for pH and bacteria. Data over the last three years indicates a pH range of 7.6 to 10.0, with over 90 percent of samples falling within the state’s water quality criteria of 6.5 to 9.0 for full body contact recreation. ADEQ’s biennial water quality assessments have consistently determined that Tempe Town Lake is “In Attainment” with full-body contact criteria for pH.
The City of Tempe has allowed partial-body-contact activities, including kayaking, rowing and sailing, on Town Lake for more than a decade. Maricopa County doesn’t require pH testing or attainment for partial body contact activities. Elevated pH levels (above the 9.0 standard) do not result in chronic health problems; the standard is a conservative threshold for temporary eye and skin discomfort similar to what one would experience in a swimming pool with a slight chemical imbalance.
Source: City of Tempe