The Tennessee Department of Transportation announced this week it agrees with a request from the Mayor of Shelby County and the Memphis Area Metropolitan Planning Organization
to reduce speed limits for commercial trucks. Signs should be in place by early summer to notify drivers about the new 55 mph regulation.
The aim is to reduce vehicle emissions and help Memphis and Shelby County attain the Environmental Protection Agency’s (EPA) federal air quality health standard for ozone. Currently, the EPA categorizes Shelby County as a marginal non-attainment area. Shelby County is the only marginal non-attainment area in the state.
According to TDOT Commissioner Gerald Nicely, “A study conducted by the Federal Highway Administration shows that reducing truck speed limits by 10 miles per hour can reduce the nitrogen oxide (NOx) emission factor by approximately 18% or more per truck. If we get reductions anywhere close to that level in Shelby County it will be worth it.”
Nicely also said the speed limit for automobiles will be reduced from 70 mph to a maximum of 65 mph in Shelby County. The specific locations of impacted roadways can be found in the TDOT media room at www.tennessee.gov/tdot.