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Aerial Larvicide Treatment - July 10th, 2024

Annex Lake (Searsville) & Sharp Park

Weather permitting, San Mateo County Mosquito and Vector Control District will conduct aerial mosquito larvicide application over water at Annex Lake (Stanford-owned property) and/or Sharp Park lagoon in Pacifica. The treatments for 2024 are scheduled for July 10th, August 7th, September 5th, and October 3rd. As usual, the schedule is subject to change due to weather conditions and mosquito abundance.

The product we’ll be using is a solid granular bio-rational mosquito larvicide; it targets mosquito larvae only and does not pose a risk to humans, pets, wildlife, fish, or the environment. It is applied by helicopter or unmanned aerial system (drone) in order to allow the product to reach the water in areas with dense vegetation, and to avoid the environmental impacts created by treating these areas on foot.

You may see or hear a helicopter or drone above or near the application area. At Annex Lake there will be no closure of public areas. At Sharp Park, some sections of the levee along the west side of the golf course will be briefly closed (5-10 minutes at a time) to allow the helicopter to land safely; if a drone is used, no closures will occur. The golf course, beach, Mori Point, and the levee in general will NOT be closed.

If you have further questions about this application please call 650-344-8592 or email

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