That is the question daunting an estimated 1.8 million California swimming pool owners who, along with the rest of us, are facing tough choices on how to conserve water. As the Golden State turns brown due to California’s extreme drought, swimming pool owners must decide – do they risk hefty fines to keep swimming pools full and useable, let them sit, or do away with them all together? In some cases, the choice is personal, but a number of cities are mandating the answer. At the same time, it turns out there’s more than the state’s much-needed water at stake, this is also a question of public health.
Mosquitoes need just two tablespoons of water in which to lay up to 400 eggs. Multiply that by a swimming pool and one pool can produce 1 million mosquitoes. And because young mosquitoes stay at the surface of the water to breathe air, a partially-filled neglected swimming pool can still produce just as many mosquitoes as a completely full pool. Many of us learned that lesson the hard way during the recent national foreclosure crisis, when more than one thousand swimming pools across Contra Costa County were abandoned resulting in neglected swimming pools producing mosquitoes capable of spreading West Nile virus. These mosquitoes can affect people up to five miles away from the pool’s location. Today, the problem is not the foreclosure crisis. It is property owners grappling with new state mandated water restrictions who run the risk of creating another and possibly larger scale public health issue if they don’t take important precautions.
Ultimately, the Contra Costa Mosquito & Vector Control District recommends swimming pool owners keep all pools and spas maintained to prevent mosquitoes, and covered when not in use to conserve water. Mosquitoes prefer slightly dirty, still water and so a chlorinated and filtered swimming pool or spa looks inviting to humans, but it deters mosquitoes. According to swimming pool service organizations, maintaining a swimming pool year-round reduces the cost of supplies and the California Pool & Spa Association cites independent studies that contend well-maintained swimming pools and spas use less water than traditional landscaping.
On the other hand, pool and spa owners who do not maintain their water features during the winter and have traditionally drained and refilled their pools each spring face bigger issues this year. With some cities prohibiting residents from refilling pools, the question is: do pool owners let them sit or should they get rid of the pools? Recent news reports show how some pool owners are opting to demolish their pools, replacing them with patios or artificial turf to prevent water use. Meanwhile, pool owners who decide to let pool water sit create a risk of producing mosquitoes that can spread mosquito-borne illness.The key is to keep even small amounts of pool water free of mosquitoes. Fortunately, we can help.
The District’s mosquitofish program provides county residents with free mosquito-eating fish for use in ponds, neglected swimming pools and spas, horse troughs and other water features. Residents are responsible for mosquito control on their own properties and using mosquitofish together with other methods will result in the best control. Our fish biologist raises one million fish every year for this program, and so there are plenty of fish to go around. Each fish can eat up to 500 larvae a day making them an efficient, natural way to prevent mosquitoes from maturing into adults capable of spreading diseases such as West Nile virus. Fish are available for pick up at the District’s office in Concord, Monday through Friday from 8:00 a.m. to 4:30 p.m.
In order to protect public health, we must prevent standing water that allows mosquitoes to flourish. In this, we can ensure that the California drought doesn’t become a public health crisis as well.
