Families all over the nation seeking relief from the blistering summer swelter are finding it harder and harder to go to the pool, as health authorities keep shutting them down.

The Florida Department of Health is busy doing its semiannual public pool inspection. Over the past year, only 62% of pool inspections in Orange County resulted in a satisfactory rating, records show. In many other cases, health inspectors, such as Andrew Burns, found the pools posed such a potential safety hazard they had to be closed.

San Diego has it even worse. The San Diego Union-Tribune obtained inspection records from the San Diego County Department of Environmental Health, and found that over 150 swimming pools and spas in the county were ordered to close at least once following an inspection, while dozens more continued to stay open in spite of multiple health and safety violations. Health authorities ordered many of the pools to close because of unclean facilities, black algae growth, or animal excrement in the pool. Some facilities even flunked repeatedly for such violations as hazardous chemical levels that can irritate or even harm swimmers, or broken gates and enclosures, which are there to prevent toddlers from accidentally drowning.

In Paxton, Illinois, the problem isn’t public pools, but private ones which have become “foul, putrid or offensive.” Police Chief Bob Bane has said that he’s having difficulty getting pools emptied because the homes are either in foreclosure, or headed towards foreclosure. Consequently, the city council has had to go so far as to amend its nuisance ordinance to include standing water.

The most common violation Andrew Burns encounters is an inadequate chlorine level. Pool water chemistry coupled with proper filtration is key in keeping water clean and healthy. It doesn’t matter if there’s 100 or 1,000,000 gallons of water, because the same balance levels and chemical types are required — only the quantity will vary. In other words, there’s not enough chlorine in the pool to keep it clean.

“There are certain diseases you can get from pools if they’re not maintained properly,” said Burns.

The moral of the story? If you have a private pool, make sure you’re keeping it clean, and maintained. Don’t let it get “putrid.” If you go to the public pools, be sure to shower before and after your dip, and don’t be too surprised if it’s shut down.