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"Municipal separate storm sewer system" or "MS4" means a conveyance, or system of conveyances (including roads with drainage systems, municipal streets, catch basins, curbs, gutters, ditches, manmade channels, or storm drains):

(1) Owned or operated by a state, city, town, borough, county, parish, district, association, or other public body (created by or pursuant to State law) having jurisdiction over disposal of wastes, stormwater, or other wastes, including special districts under State law such as a sewer district, flood control district or drainage district, or similar entity, or an Indian tribe or an authorized Indian tribal organization, or a designated and approved management agency under section 208 of the CWA that discharges to waters of the State.

(2) Designed or used for collecting or conveying stormwater.

(3) Which is not a combined sewer.

(4) Which is not part of a publicly owned treatment works (POTW) as defined at 40 CFR 122.2.

(5) Which is defined as "large" or "medium" or "small" or otherwise designated by Ecology pursuant to 40 CFR 122.26.

The "existing" MS4 means all elements of the system that are in place and operating at the time of a project’s initial permit application. The "planned" MS4 includes future elements of the system that are either (1) under construction; (2) included in the system operator’s adopted six-year capital improvement program, or comparable capital plan; or (3) included in any private development project that has submitted a complete application. (Added by Amended Ord. 10-026, June 9, 2010, Eff date Sept. 30, 2010; Amended by Ord. 15-103, Jan. 11, 2016, Eff date Jan. 22, 2016).