According to , TxDOT must construct, repair, and maintain roads in and adjacent to state parks, state fish hatcheries, state wildlife management areas, and support facilities for parks, fish hatcheries, and wildlife management areas.

In response to this legislation, a memorandum of agreement between TxDOT and TPWD was established. This memorandum of agreement states that TPWD is to provide TxDOT with current design standards for TPWD facilities.

Accordingly, TPWD facilities, which are those designated as Park and Wildlife Roads (PW), are to be designed based on the criteria and guidance given in the current publication of the .

Park Roads (PR) that lead to or enter a state park, and are designated on the State Highway System, are to be designed based on the criteria and guidance given in the current RDM. For roads designated as PR where constrained site conditions, parking, or high pedestrian usage warrant a lower speed, a design speed of no lower than 20-mph may be used.