Health & Saf. Code, § 4602.4

Improvement means any or all of the following:

(a) The acquisition or construction of sanitary sewers of all types, including, but not limited to, outfall, trunk, intercepting, connecting, lateral, and house connection sewers.

(b) The acquisition or construction of sewage treatment plants, works, or systems.

(c) The acquisition or construction of other improvements, works, or system for the collection, transmission, treatment, or disposal of sewage or industrial waste.

(d) The acquisition or construction of sewers, drains, pipelines, conduits, culverts, or ditches for the collection, transmission, or disposal of surface or storm water.

(e) The acquisition or construction of other improvements, works, or system for the purpose of surface or storm water drainage or for the purpose of flood control.

(f) The acquisition, construction, or extension of waterworks, water systems or water distribution systems.

(g) The acquisition or construction of works or improvements appurtenant or related to any of the works, improvements, or systems described in subdivisions (a) to (f), inclusive.

(h) Additions to, or the reconstruction or improvement of, any of the works, improvements, or systems described in subdivisions (a) to (g), inclusive.

(i) The acquisition of any land, rights-of-way, capacity rights, rights of use, or other property needed for any of the works, improvements, or systems described in subdivisions (a) to (h), inclusive.