Highway Traffic Noise Barrier Materials and Cost By State - Introduction

It should be noted that the cost data in the listing are approximate due to differing State practices for estimating costs and due to the fact that for some barriers (50 miles), the cost could not be estimated at all. The data represent best estimates of SDOTs for barrier construction. There may be non-uniformity and/or anomalies in the data due to differences in individual SDOT definitions of barrier information.

It should also be noted that California did not provide data from 1999 through 2004. This fact greatly affects data for these years, since California constructs many noise barriers annually (119 miles costing 150 million in 2004 dollars for 1994-1998) and California has constructed nineteen percent (19%) by area of all noise barriers to date.