Alameda County Mosquito Abatement District conducts ground-based larvicide and adulticide treatment applications to manage mosquito populations and protect public health in Alameda County. These treatments are an important part of our comprehensive integrated vector management program.  Scheduled treatments may be canceled due to unstable weather conditions or other unforeseen reasons.

 Ground WALS Treatment Schedule

WALS stands for Wide Area Larvicide Spray. WALS is an approach to larval control that uses a form of larvicide, which targets immature mosquitoes in the water using a naturally occurring bacterium to kill mosquito larvae before they emerge into biting adults. Control of mosquitoes while in the larval stage is the backbone of most mosquito control programs in California. 

Latest Treatment Update Notifications

October 10th 2025 Larval treatment for eastern Livermore on Oct 10th, 3am to 5am 

October 9th 2025 Detection of Invasive Mosquito in Northern Fremont Larval Treatment on October 9th, 2025 from 4am to 5 am

October 7th 2025 Larval treatment for eastern Livermore between S. Vasco Rd and East Ave on Oct 7th 

September 26th 2025 New detection of multiple Aedes aegypti mosquitoes prompt larval treatment on September 26th in Jensen and Windmill Springs neighborhoods 

September 5th 2025 Larval treatment for Aedes aegypti scheduled for Sept 5th in Altamont Creek neighborhood of Livermore