Why are there so many mosquitoes in San Fernando Valley?

In 1979, the Army Corps of Engineers establish a Wildlife Reserve as part of the San Fernando Valley flood abatement program. This surrounding parks, lakes, and golf courses has created an iconic recreational area in the valley but this is also part of the epicenter for the Valley’s mosquito breeding grounds. With all the rains this year, these areas have extensive marshy areas with lush vegetation which is ideal for mosquitoes. Studies have shown that when mosquito density reaches a certain point, mosquitoes spread to other areas by riding wind currents. The valley is notorious for its wind with the predominant Northwest to Eastern and the Santa Anas which run Southeast to Northwest which enable the migration and dispersion of mosquitoes throughout the valley.