Unless the context clearly requires otherwise, the definitions in this section apply throughout this chapter.

(1) “Water pollution control facilities” or “facilities” means any facilities, systems, or subsystems owned or operated by a public body, or owned or operated by any person or entity for the purpose of providing service to a public body, for the control, collection, storage, treatment, disposal, or recycling of wastewater, including but not limited to sanitary sewage, stormwater, residential wastes, commercial wastes, industrial wastes, and agricultural wastes, that are causing or threatening the degradation of subterranean or surface bodies of water due to concentrations of conventional, nonconventional, or toxic pollutants. Water pollution control facilities do not include dams or water supply systems.

(2) “Public body” means the state of Washington or any agency, county, city or town, political subdivision, municipal corporation, or quasi-municipal corporation.

(3) “Water pollution” means such contamination, or other alteration of the physical, chemical, or biological properties of any surface or subterranean waters of the state, including change in temperature, taste, color, turbidity, or odor of the waters, or such discharge of any liquid, gaseous, solid, radioactive, or other substance into any waters of the state as will or is likely to create a nuisance or render such waters harmful, detrimental, or injurious to the public health, safety, or welfare, or to domestic, commercial, industrial, agricultural, recreational, or other legitimate beneficial uses, or to livestock, wild animals, birds, fish, or other aquatic life.

(4) “Agreement” means any agreement to which a public body and a service provider are parties by which the service provider agrees to deliver service to such public body in connection with its design, financing, construction, ownership, operation, or maintenance of water pollution control facilities in accordance with this chapter.

(5) “Service provider” means any privately owned or publicly owned profit or nonprofit corporation, partnership, joint venture, association, or other person or entity that is legally capable of contracting for and providing service with respect to the design, financing, ownership, construction, operation, or maintenance of water pollution control facilities in accordance with this chapter.