Merced County, CA Noise Ordinances: Aircraft Noise (2026)

The County General Plan's Noise chapter identifies aircraft operations associated with five public airports as a major noise source in Merced County: Merced Municipal Airport, Castle Airport, Los Banos Municipal Airport, Gustine Airport, and Turlock Municipal Airport. Castle Airport, just north of Atwater and formerly Castle Air Force Base, is the busiest, with about 3,854 aircraft operations per week, roughly 80 percent of which are pilot training. Aircraft noise in flight is governed by the Federal Aviation Administration and federal law, not by the County's Chapter 10.60 noise ordinance; in fact the noise code's standards focus on ground-based and property-line sources. Instead, Merced County addresses aircraft noise through land-use compatibility planning. The General Plan and the County's Airport Land Use Commission use noise contours (such as the 60 and 65 dB CNEL/Ldn lines) to guide development near airports and to require acoustical studies for noise-sensitive uses, like new homes, proposed within high-noise areas. Standard residential construction provides roughly 10 to 15 dB of exterior-to-interior noise reduction with windows open and about 25 dB with windows closed, which informs mitigation requirements near airports. Residents with persistent aircraft-noise concerns are generally directed to the airport operator and the FAA.