Creates the office of Chehalis basin in the department of ecology to aggressively pursue implementation of an integrated strategy and administer funding for long-term flood damage reduction and aquatic species restoration in the Chehalis river basin.

Requires the office to be funded from appropriations specified for Chehalis river basin-related flood hazard reduction and habitat recovery activities.

Requires the department of ecology, in operating the office, to follow, to the greatest extent practicable, the model being used to administer the Columbia river basin water supply program established in chapter 6, Laws of 2006.

Creates the Chehalis board that will be responsible for: (1) Oversight of a long-term strategy resulting from the department of ecology's programmatic environmental impact statement for the Chehalis river basin to reduce flood damages and restore aquatic species habitat; and

(2) Overseeing the implementation of the strategy and developing biennial and supplemental budget recommendations to the governor.

Creates the Chehalis basin account.