1. (1) Noise barriers shall be designed to provide protection only to the ground floor of abutting buildings and not other parts of the buildings.

2. (2) For the department to consider a site for construction of a noise barrier, the site shall meet the following criteria:

   1. (a) For retrofit projects, a receptor shall be exposed to existing noise levels which equal or exceed the levels in Table 1.
   2. (b) For new highway projects, a receptor shall have predicted future noise levels which equal or exceed the levels in Table 1 or which exceed existing noise levels by 15 decibels or more.
   3. (c) A noise barrier protecting a receptor shall reduce noise levels by a minimum of 8 decibels.

   4. (d) The total cost of a noise barrier may not exceed $30,000 in 1988 dollars per abutting residence. The department may annually adjust this $30,000 maximum figure up or down based on changes in the construction price index after 1988. Other land use categories shall be analyzed on a site specific basis to determine cost effectiveness.

      - See PDF for table

History

History: Cr. Register, August, 1989, No. 404, eff. 9-1-89; reprinted to correct error in table, Register, November, 2000, No. 539.