Minimizing mosquito larval habitat within roadside stormwater treatment best management practices in southern California through incremental improvements to structure

•Stormwater treatment Best Management Practices can unintentionally produce mosquitoes.•BMP design and non-stormwater runoff contribute to standing water suitable for mosquito larval development.•Mosquito larval habitat can be mitigated via structural modification, elimination of non-stormwater flows, and maintenance.•Mosquito larval habitat can be minimized in BMPs without impacting water quality objectives.