To authorize the Secretary of the Interior to participate in the design, planning, and construction of the Willow Lake Natural Treatment System Project for the reclamation and reuse of water, and for other purposes.

Amends the Reclamation Wastewater and Groundwater Study and Facilities Act to authorize the Secretary of the Interior to participate in the design, planning, and construction of the Willow Lake Natural Treatment System Project for the reclamation and reuse of wastewater within and outside of the service area of Salem, Oregon. Limits the Federal share of project costs to 25 percent. Prohibits the Secretary from providing funds for project operation and maintenance.