Abstract: At Salt Lake City Mosquito Abatement District (SLCMAD) the vast majority of the mosquitoes arise from wetlands to the west of the city, next to the Great Salt Lake. During the summer months aerial ULV applications are the most effective means to control mosquitoes from this large habitat. SLCMAD evaluates how effective the aerial ULV applications are through monitoring mosquito populations, collecting droplets and using sentinel mosquitoes. In 2022 SLCMAD did an evaluation of the product Duet HD, which had not been used previously in the District. Some of the challenges to conducting aerial ULV applications in SLCMAD include low humidity, high elevations, erratic winds from being between the Rocky Mountains and the Great Salt Lake, an international airport adjacent to application areas and now a new state prison in the middle of the wetlands. Because of these environmental conditions and the restrictions from the airport we have our best control from dense products.The methods, equipment, and results of the evaluation conducted just west of the Rocky Mountains will be discussed in this presentation.