The existing transportation setting in the Morongo Basin consists of the backbone access roadways along State Route 62 (SR-62) and State Route 247 (SR-247). These regional facilities provide access to developed areas in the basin, including Yucca Valley, Joshua Tree and Twentynine Palms. The existing traffic volumes are relatively low on facilities throughout the study area and all analyzed roadway segments currently operate below capacity.
The SCAG 2016-2040 Regional Transportation Plan/Sustainable Communities Strategy (2016-2040 RTP/SCS) socioeconomic forecasts predict growth in population and employment throughout the region. These regional forecasts were used to update the base year and future year San Bernardino Transportation Analysis Model (SBTAM). The base year model was modified and validated to existing conditions for use in the study. The future year roadway network was modified to replicate the base year roadway network in terms of roadways, number of lanes, roadway classifications and speeds. Future model runs were completed on this constrained network to determine which facilities were most likely to become deficient as growth occurs.
Roadway and intersection improvements were identified as necessary to serve the forecast future traffic demand. The three corridors that require improvements are SR-62, SR-247 and Yucca Mesa Road. Cost estimates were produced based on roadway widening and traffic signal installations or modifications. An implementation schedule was also identified which recommends segment prioritization and recommended implementation dates in order to provide sufficient capacity for the future traffic demand.