SR 177 begins at I-10 near Desert Center and briefly travels north, intersecting with CR R2. At this intersection, SR 177 turns northeast and travels across the Mojave Desert, through the Chuckwalla Valley. It passes near the Desert Center Airport and comes near Palen Lake, a dry lake. The highway passes along the southeastern boundary of Joshua Tree National Park before turning due north and crossing the desert for several miles. SR 177 briefly turns northeast again before intersecting with SR 62 and defaulting onto SR 62 eastbound.[3]
The route is two lanes wide for its entire length.[4] SR 177 is not part of the National Highway System,[5] a network of highways that are considered essential to the country's economy, defense, and mobility by the Federal Highway Administration.[6] In 2013, SR 177 had an annual average daily traffic (AADT) of 1,200 at the northern terminus with SR 62, and 3,700 at the southern terminus with I-10, the latter of which was the highest AADT for the highway.[7]
History
The Metropolitan Water District built a road from Desert Center that ran north before turning east to Earp along with portions of the Colorado River Aqueduct from February 20 to August 4 in 1933. This was part of a road system that was built in order to support the construction of the aqueduct by connecting the camps that construction workers resided in during the project. This road cost $389,600 (about $7 million in 2023 dollars)[8] to construct; the roads in the system were paved.[9] SR 177 was added to the state highway system in 1972 by the California State Legislature.[10] As of 1998, Caltrans had no plans to expand the highway, considering it to be "maintain only" through 2015.[4]
Major intersections
Except where prefixed with a letter, postmiles were measured on the road as it was when the route was established, based on the alignment that existed at the time, and do not necessarily reflect current mileage. R reflects a realignment in the route since then, M indicates a second realignment, L refers to an overlap due to a correction or change, and T indicates postmiles classified as temporary (for a full list of prefixes, see California postmile § Official postmile definitions).[1] Segments that remain unconstructed or have been relinquished to local control may be omitted. The entire route is in Riverside County.
^ abcCalifornia Department of Transportation. "State Truck Route List". Sacramento: California Department of Transportation. Archived from the original(XLS file) on June 30, 2015. Retrieved June 30, 2015.
^Federal Highway Administration (March 25, 2015). National Highway System: California (South)(PDF) (Map). Scale not given. Washington, DC: Federal Highway Administration. Retrieved May 25, 2015.
^Natzke, Stefan; Neathery, Mike & Adderly, Kevin (June 20, 2012). "What is the National Highway System?". National Highway System. Washington, DC: Federal Highway Administration. Retrieved July 1, 2012.
^ abCalifornia Department of Transportation (2013). "All Traffic Volumes on CSHS". Sacramento: California Department of Transportation.
I-10 near Desert Center
SR 62 near Rice
