DOTD announces speed limit increase along I-49 in DeSoto Parish
Tuesday, April 12, 2011 at 11:14:57 AM

BATON ROUGE, La. – The Louisiana Department of Transportation and Development (DOTD) announced today that the speed limit on the rural portion of I-49 DeSoto Parish will be raised from 70 mph to 75 mph.

DOTD engineers study speed limits on state maintained roadways to ensure they are set correctly. Recently, the DOTD traffic engineering office in Shreveport launched a traffic study to help determine what the safest and most efficient posted speed limit should be on the rural portions of I-49. After reviewing the results of the study, it was determined that 85% of all drivers traveling on this section of I-49 are traveling at or below 75 mph. The new speed limit will go into effect in the next 2 weeks.

National studies and practices have shown that setting the speed limit at the 85th percentile can help to reduce crashes along the roadway. Speed limits set higher than the 85th percentile are not considered reasonable and safe, and speed limits set below the 85th percentile do not move traffic efficiently. In addition, speed limits set below the 85th percentile cannot be enforced effectively and are not voluntarily observed by motorists.

The new speed limit will be in effect from 1.5 miles south of the La. 175 interchange to the Natchitoches Parish line. The highway features on this section of roadway can safely accommodate higher speeds.

To ensure the safety of motorists, DOTD personnel will install automated speed and count stations along the roadway to monitor speeds and crashes along this section of I-49. DOTD will reexamine the speed limit increase if at any time data supports a new study.

DOTD is committed to delivering transportation and public works systems that enhance the quality of life. In addition to more than 16,600 miles of roadway, including over 890 miles of interstate, DOTD supports the development of the state’s aviation, marine and rail infrastructures. Through this work, we are able to facilitate economic development, create job opportunities, improve vital evacuation routes, and make critical freight corridors safer and more efficient.

For more information, please visit, email, or call DOTD’s Customer Service Center at (225) 379-1232 or 1-877-4LADOTD (1-877-452-3683). Business hours are 7:30 a.m. - 5 p.m., Monday through Friday.

Motorists can access up-to-date travel information by dialing 511 or by visiting Out of-state travelers can call 1-888-ROAD-511 (1-888-762-3511).