# California coastal sea level rise and erosion > Live situation record from CLSTR: https://clstr.news/situations/california-coastal-sea-level-rise-and-erosion > Updated: 2026-09-10T23:12:14.000Z. Sources: 5. Developments: 2. Oceanographic shifts driven by El Niño are causing sea levels to rise along the California coast. Initial reports indicated that Kelvin waves moving north from Mexico and Central America were expected to raise sea levels by approximately 30 centimeters by mid-October, increasing the risk of damage from winter storms and high tides. As conditions progressed, coastal communities in Southern California began facing immediate impacts. The city of Carlsbad declared a local emergency to address significant coastal erosion threatening Highway 101, allowing for expedited stabilization efforts. In Dana Point, several homes were red- or yellow-tagged due to structural dangers, and Laguna Beach declared an emergency following sand erosion and sea wall damage. Experts noted that the “coastally trapped Kelvin wave” is combining with marine heatwaves and long-term climate change to exacerbate risks to oceanfront infrastructure. ## Timeline ### 2026-09-10: California coastal communities declare emergencies amid rising sea levels California coastal communities, including Carlsbad, are declaring emergencies as El Niño and Kelvin waves threaten to raise sea levels and accelerate coastal erosion and property damage. 2 sources. https://clstr.news/cluster/california-coastal-communities-declare-emergencies-amid-rising-sea-levels ### 2026-09-08: California sea levels to rise by 30cm due to El Niño El Niño is expected to raise California's sea levels by approximately 30 centimeters by mid-October, increasing the risk of coastal flooding and storm damage due to moving Kelvin waves. 3 sources. https://clstr.news/cluster/california-sea-levels-to-rise-by-30cm-due-to-el-nio --- Cite as: California coastal sea level rise and erosion. CLSTR, https://clstr.news/situations/california-coastal-sea-level-rise-and-erosion