Game theoretic approaches for highway infrastructure protection against sea level rise: Co-opetition among multiple players

•We investigate decision-makers’ behavior for highway infrastructure protection.•Algorithms for co-opetitive games among multiple players are developed.•Findings are applied to a real-world network in California for 0.5 m sea level rise.•Budget constraints, hydrodynamic effects, and traffic interactions are considered.•Cooperation is beneficial in most budget cases compared to competitive actions.