City of La Quinta, CA

La Quinta is nearly surrounded by the Santa Rosa Mountains and is located on the floor of the Coachella Valley. When the floor of the valley began to sink, it was covered by the Pacific Ocean. Over a period of hundreds of years, the Colorado River flowed into the Gulf of California and formed a large delta fan. Silt basin deposits grew higher and wider until the basin was cut-off from the ocean, while the mountains on both sides grew higher. When the Colorado River changed its course five hundred years ago, the east Coachella Valley flooded creating the freshwater Lake Cahuilla. You can still see the lake's water line today along the base of the Santa Rosa Mountains.