Recreational Water Quality Program

There are many places in San Mateo County where people can go to swim, surf, wade or just enjoy the water. The goal of the Recreational Waters Program is to make sure that it is safe for citizens to use public swimming pools and beaches.

Public Swimming Pools

Swimming pools, hot tubs and wading pools are open to the public at parks, health spas, fitness centers and schools. Inspection staff check these pools twice each year.

If you use on of these pools, here's what to look for to protect yourself and your family:

  • The water should be clear.
  • There should be no strong odor of chlorine.
  • Safety equipment (poles and life rings) should be within easy reach.
  • There should be safety precautions, such as fences with self-closing gates and safety signs.
  • There should be no tripping hazards.
  • There should be adequate lighting inside the pool and surrounding area.
  • Locker rooms and showers should be clean.

If you find unsanitary or unsafe conditions at public pools, notify the Recreational Waters Program at 650-372-6200.


Inspection staff take water samples from various recreational beach areas. These include the Pacific Ocean, San Francisco Bay, aquatic parks, lagoons and lakes. Samples are tested for bacteria levels to make sure the beaches are safe for people to use. When test results show high contamination levels, warning signs are posted. These signs discourage any contact with the water. Visit our Beach Closure web page for the latest information on closed beaches in San Mateo County.

Shellfish Harvesting

San Mateo County citizens can harvest their own mussels or clams along the Pacific coastline. Between May and October, environmental conditions cause these foods to be toxic and a quarantine is put into effect. You can become seriously ill from eating mussels or clams taken during those months.

Inspection staff assist the State by collecting mussel samples for analysis during the quarantine period and throughout the year. They help educate the public about the mid-year quarantine and they notify the public if mussels or clams are dangerous to eat during the non-quarantine times.