When barrier or rail is used, it may present a challenge for wildlife to traverse when crossing a highway facility. In these areas, the designer may consider using Hydraulically Efficient Barrier (HEB). While this type of barrier is generally used to increase hydraulic efficiency, it may also be used to allow smaller wildlife to cross the highway more easily due to the larger slot openings at the bottom of the barrier. Refer to for additional information and design details on HEBs.