The focus of this study was to compare larval mosquito diversity and abundance among five types of stormwater BMPs: shallow marshes, retention ponds, detention ponds, infiltration basins and infiltration trenches. We sampled stormwater BMPs (5 types X 6 replicates/type=30). While the selection of all BMP ponds was based on sampling and time logistical constraints, all sites were located randomly adjacent to highways or major roads as well as residential neighborhoods throughout Howard, Montgomery, Baltimore and Prince Georges counties. Stormwater BMPs were approximately the same age since construction (+/- 2 years). Larval mosquitoes (n=50 dips/site) were collected using 250ml mosquito dippers from the periphery of each site every two weeks from June – September,2004. Larval control efforts using Bacillus thuringiensis var. israelensis were implemented in August, 2004 on three replicate sites per type (n=15 treated sites), there were three control sites per type (n=15 control sites). In 2004, larval diversity increased since 2003 in retention, detention and shallow marsh BMPs and except for infiltration trenches, did not differ among BMPs in 2004. Control efforts significantly reduced the number of mosquito larvae in treated v. untreated BMPs. Because stormwater BMPs change or evolve over time, it is important to understand how mosquito populations change as well, thus, it is critical to maintain monitoring efforts to more fully understand this relationship and because stormwater management is federally mandated, it is likely that mosquito abatement programs will have to accompany stormwater management.