Fort Riley Noise Zones
The following provides an explanation of the various noise zones shown on the 'Fort Riley Average Noise Levels' map:
Noise Zone III – the area around a noise source in which the C-weighted day-night sound level (CDNL) is greater than 70 dB (demolition and large caliber weapons), the A-weighted day-night level (ADNL) is greater than 75 dB (aviation), or the dB Peak is greater than 104 (small caliber weapons). The average large caliber weapons firing noise level in this zone is generally considered to conflict with almost all activities and to, particularly conflict with sensitive land uses, such as housing, schools, medical facilities, and places of worship.
Noise Zone III currently does not occur off the installation.
Noise Zone II – the area around a noise source in which the CDNL is 62-70 dB (demolition and large caliber weapons), the ADNL is 65-75 dB (aviation), or the dB Peak is 87-104 (small caliber weapons). The Army recommends limiting the use of land in this to activities that are not noise-sensitive - such as industry, manufacturing, transportation and agriculture.
Noise Zone I – included all areas around a noise source in which the CDNL is less than 62 dB (demolition and large caliber weapons), the ADNL is less than 65 dB (aviation), or the dB Peak is less than 87 (small caliber weapons). This area is usually suited for all types of land use activities.
Land Use Planning Zone (LUPZ) - The noise environment at the installation varies daily and seasonally because operations are not consistent 365 days a year. To provide a planning tool that can be used to account for days of higher than average operations, a LUPZ is included on this noise zone map. The LUPZ is 5 dB lower than Zone II and encompasses areas where, during periods of increased military operations, community annoyance levels can reach those associated with Zone II. The LUPZ can offer a prediction of noise impacts when levels of operations are above average. While residential and other noise sensitive land uses may generally be compatible with the typical noise levels present within a LUPZ, potential increased annoyance levels during training operations may warrant the utilization of design and structural noise level reduction measures, to reduce interior noise levels during periods of increased military operations. Additionally, low residential densities are warranted within the LUPZ to reduce the likelihood of potential future land use conflicts.
In 2019, a document entitled “Noise Attenuation Guidelines” (pdf), prepared for the Flint Hills Regional Council by Henderson Engineers, Inc., was completed and adopted following a detailed study of noise impact resulting from training activities on Fort Riley. The document includes a discussion of the type of noise generated by Fort Riley and suggestions for building methods that could help reduce the interior noise impacts. It is recommended by local authorities that property owners consider using these construction methods in new construction or remodeling projects, particularly for noise sensitive land uses (residential, churches, hospitals, offices., etc.) that are located in the Land Use Planning Zone (LUPZ) or Noise Zone II.