(a) Authority to set variable speed limits. House Bill 2204, 83rd Legislature, Regular Session, 2013, requires the commission to establish, and the department to implement, a variable speed limit pilot program to study the effectiveness of temporarily lowering prima facie speed limits to address inclement weather, congestion, road construction, or any other condition that affects the safe and orderly movement of traffic on a roadway. The executive director of the department will select the areas of the state in which the pilot program will be conducted. The department's district engineers in the selected areas are responsible for establishing the reduced speed limits for the affected roadways and the periods of effectiveness based on the criteria provided in this section. A district engineer may delegate that authority to the districts' deputy district engineer, director of construction, director of operations, or director of maintenance, or a director of transportation operations or a traffic engineer for the district.
(b) Criteria for variable speed limits. The established prima facie speed limits on a portion of the state highway system may be lowered as necessary for the safe and orderly movement of traffic as a result of traffic volume, adverse weather conditions, highway construction work zones, or traffic crashes and incidents. These reduced speed limits must be based on an engineering and traffic investigation and will be lowered only in multiples of five miles per hour.
(c) Engineering and traffic study. The engineering and traffic study required to establish the variable speed limit may include the determination of a spot speed within the affected area, speed-over-distance readings from automated field technology, sight distance during inclement weather, or traffic flow obtained by either field investigation or automated technology. An 85th percentile speed study is not required for establishing a variable speed limit.
(d) Sign placement. A speed limit established under this section is effective only when a sign indicating the change in the speed limit is displayed between 500 and 1,000 feet before the point at which the speed limit takes effect. A sign will also be posted at the point where the speed limit takes effect. The department may use an electronic sign that is capable of displaying more than one message for posting a reduced speed limit.
(e) Documentation of lowered variable speed limits. The department will keep an official record of all changes made to prima facie speed limit established for an affected roadway that includes the date, time, and duration of the lowered speed limit.
(f) Coordination. The department will coordinate closely with state and local law enforcement agencies regarding the locations and reduced speed limits at all variable speed limit sites. The department will make records maintained under subsection (e) of this section available to state and local law enforcement entities in order to support speed limit enforcement.
(g) Expiration. This section expires February 1, 2015.

Source Note: The provisions of this §25.27 adopted to be effective December 12, 2013, 38 TexReg 8928