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District Procedures for Inspecting Neglected Swimming Pools

May contain: pool, water, hot tub, tub, and person

To report a neglected swimming pool, please call (925) 685-9301 or click here to make a report online (anonymous reports accepted).


Not only are they unsightly, but neglected pools/spas can pose a threat to public health. Mosquitoes need very little standing water to complete their life cycle. Swimming pools and spas that are not maintained can be an ideal source for more than 1 million mosquitoes that may go on to become infected with West Nile virus. These mosquitoes may affect people up to five miles away. While it is not illegal to have a green swimming pool, it is illegal to produce mosquitoes. Below are some measures the District can enforce with regard to neglected pools/spas that produce mosquitoes.

The first course of action upon notification of a pool with potential mosquito production: Contact is made with the homeowner and they are asked if we may inspect the pool.

If inspection is denied: A judge can issue a warrant to inspect the pool based on the technician’s observations and/or mosquito trap data.

If mosquitoes are found: An employee will treat the pool to eliminate mosquitoes free of charge. The resident/Tenant will be required to take action(s) to ensure further mosquito production does not occur.

Possible remedies include:

1. Drain the pool or contact your local wastewater treatment authority.


2. Clean, filter, and maintain the pool in an operating condition;

3. Request mosquito-eating fish. Weekly inspections by the resident/tenant will be required to ensure the fish are present and working. Supplemental treatments of a pesticide for mosquito larvae control may also be needed.

Two weeks after treatment has occurred: An employee will return for a follow-up appointment to ensure mosquito production has been addressed. Significant progress toward this goal should be evident.

If the resident/tenant of an inspected pool that was treated does nothing to correct the problem: A supervisor will post a 72-hour notice for the resident/tenant to make corrections to eliminate mosquito production.

If the resident/tenant still refuses to cooperate: Fines will be issued. Administrative citations will be written by the District’s Operations Manager or city Code Enforcement personnel. Fines begin at $100 and can go as high as $1,000/day. If fines are not paid, a lien on the property can occur.

In summary, the District would prefer to work with the resident/tenant to resolve the problem. It is not illegal to have a green pool, however, it is illegal to have a green pool that is producing mosquitoes.