The districts are now under the control of the Clean Water Act.  It says spraying of a certain type of insecticide called pyrethrins (pie REETH rins) is prohibited if they have already been found in nearby waterways.   The House passed a bill last year removing pesticide spraying from the oversight of the clean water act.  Ada Barros with Placer County's district says the bill has stalled in the senate.

BARROS: There are some areas in California where there is a direct impact on the materials we are able to use to control adult mosquitoes which we know are the ones that able to transmit diseases."

Opponents of the bill in the Senate say it would provide a permanent, un-needed exemption from the Clean Water Act.

The California State Water Board says it is now trying to find a solution at the state level.