YOU MIGHT NOT LIVE TO YEAR 2100 BUT YOUR PROJECT MIGHT - SEA LEVEL RISE & BEST AVAILABLE SCIENCE

In June 2024, the California Ocean Protection Council (OPC) updated its State of California Sea Level Rise Guidance document and included updated sea level rise projections through year 2150. OPC’s update now serves as the “best available science” in California when assessing sea level rise in development projects and policy documents such as Local Coastal Programs (LCP). OPC’s updates have made their way into the latest draft of the California Coastal Commission's (CCC) Sea Level Rise Adopted Policy Guidance document that was recently published for public review in July 2024. This is important because the CCC’s Guidance document is intended to guide project design and adaptation measures for proposed development projects when pursuing a Coastal Development Permit (CDP) via a city, county or the CCC directly. The document also guides cities and counties when updating their LCPs to ensure coastal resource protection considers long-term planning horizons in their policies and regulations. CCC’s Draft Guidance will be presented at the August and September 2024 CCC meetings, and planned to be formally adopted later this year. Once adopted, it would amend the CCC’s current 2018 Guidance.

One takeaway when comparing CCC’s 2018 Guidance versus its Draft Guidance - OPC’s updated projections are lower than the projections included in CCC’s 2018 Guidance and the “H++" all-out extreme scenario has been removed from the projection scenarios. For example, CCC’s 2018 Guidance included 6.9 ft (Medium-High scenario) and 10.2 ft (H++ Extreme Risk scenario) for year 2100. CCC’s Draft Guidance reduces this to 4.9 ft (Intermediate-High scenario) and 6.6 ft (High scenario) for year 2100.

CCC’s Draft Guidance recommends projects consider, at minimum, the“Intermediate-High” scenario in the updated scenario table. This means that by year 2100, a project should consider at least 4.9 ft of sea level rise in its design, site development accordingly, and include adaptation measures that correspond to the expected sea rise situation on the project site. CCC’s Draft Guidance also recommends that existing and proposed assets that have little to no adaptive capacity, such as critical infrastructure projects should also consider the “High” scenario that projects 6.6 ft of sea level rise by year 2100. Per the CCC's Draft Guidance, these types of assets are those that could be “irreversibly destroyed or significantly costly to repair, and/or would have considerable public health, public safety, or environmental impacts” should 6.6 ft of sea level rise occur by year 2100. Further, there is a trending goal in CCC’s Draft Guidance to also consider a true 100-year horizon from current day, which means development projects may want to go beyond the traditional year of 2100 and use 2130 as a long-term planning horizon in their analysis. For the “Intermediate-High” scenario, this equals 7.1 ft of sea level rise by 2130 and 10 ft under the “High” scenario.

Pro Tip: In your development project, be sure to analyze up to 4.9 ft of sea level rise by year 2100. For those seeking additional certainty in their coastal development permits, push your analysis out to horizon year 2130 and assess 7.1 feet of sea level rise. Deep breaths...you got this.