The Centers For Disease Control and Prevention (CDC) has issued clarification and guidance on COVID-19 and treated recreational water venues. The advice and answers provided are useful to swimmers.

Water Transmission and COVID-19

Drinking Water, Recreational Water and Wastewater: What You Need to Know Can the COVID-19 virus spread through drinking water?

The COVID-19 virus has not been detected in drinking water. Conventional water treatment methods that use filtration and disinfection, such as those in most municipal drinking water systems, should remove or inactivate the virus that causes COVID-19. Is the COVID-19 virus found in feces?

The virus that causes COVID-19 has been detected in the feces of some patients diagnosed with COVID-19. The amount of virus released from the body (shed) in stool, how long the virus is shed, and whether the virus in stool is infectious are not known.

The risk of transmission of COVID-19 from the feces of an infected person is also unknown. However, the risk is expected to be low based on data from previous outbreaks of related coronaviruses, such as severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS). There have been no reports of fecal-oral transmission of COVID-19 to date. Can the COVID-19 virus spread through pools and hot tubs?

There is no evidence that COVID-19 can be spread to humans through the use of pools and hot tubs. Proper operation, maintenance, and disinfection (e.g., with chlorine and bromine) of pools and hot tubs should remove or inactivate the virus that causes COVID-19.

https://www.cdc.gov/coronavirus/2019-ncov/php/water.html