HMMH conducted noise barrier final design studies for Type II (retrofit) noise barriers in two locations along the Brooklyn-Queens Expressway (BQE). The study areas involved complex acoustical environments including aircraft overflights from nearby LaGuardia Airport, trains on elevated structures, both depressed and elevated expressway mainline combined with frontage roads, and reflections from retaining walls and existing noise barriers. HMMH conducted field measurements to assist in validating noise modeling and performed noise barrier analyses using the FHWA’s Traffic Noise Model. The analysis determined that, for one project area, it was not possible to design a noise barrier to meet NYSDOT’s acoustical requirements without substantial reconstruction of the existing BQE structure. For the second project area, a noise barrier was designed to benefit 30 residences in townhouses adjacent to the expressway.