Requiring data centers to use closed-loop cooling systems to mitigate water consumption.

SB 400 requires large data centers in Kansas (defined as facilities with 20+ megawatts monthly electrical demand) to switch from open-loop cooling systems - which release water vapor into the air - to closed-loop systems that recirculate water without atmospheric discharge. This directly affects major data center operators by mandating a specific cooling technology to reduce on-site water consumption. The bill also authorizes the attorney general or local prosecutors to seek court injunctions against violations, ensuring enforcement through legal remedies. The law takes effect after publication in Kansas statutes.