CA SB639

Extends the deadline from 2025 to 2030 for achieving urban level flood protection in specific flood-prone areas: the Natomas and Beach Lake subareas of Sacramento, portions of Sacramento County, Sutter County, and the City of Marysville protected by the Marysville Ring Levee

Cities and counties in the Sacramento-San Joaquin Valley cannot approve development agreements, discretionary permits, ministerial permits for new residences, or subdivision maps in flood hazard zones unless flood protection requirements are met or adequate progress is being made

Authorizes the Department of Water Resources to require the City of Marysville, City of Sacramento, Sacramento County, Sutter County, or Yuba County to contribute their fair share of flood-related property damages if they unreasonably approve new development before achieving urban level flood protection

Defines specific geographic boundaries for the Natomas subarea, Beach Lake subarea, and City of Marysville areas subject to the extended 2030 deadline

Declares the legislation necessary as a special statute due to the unique flood susceptibility of these Sacramento-San Joaquin Valley jurisdictions