“Clean stormwater activities” includes but is not limited to all programs required by the Marin County Stormwater Pollution Prevention Program and the BURCP Basin Plan Permit, the operation and maintenance of the City’s stormwater drainage system, any capital improvements to repair, rehabilitate, replace, or improve components of the stormwater drainage system, the enforcement of the runoff pollution prevention ordinance (Larkspur Municipal Code Chapter 9.11) and related regulations, the administration of this chapter and of Larkspur Municipal Code Chapter 9.11 , and any other activities related to the foregoing.

“Land use category” means that category of land use assigned to a parcel of real property as shown on the most current official assessment roll of the Marin County Assessor.

“Parcel” means a unit of real property in one ownership as shown on the most current assessment roll of the Marin County Assessor.

“Parcel size” means the area of a unit of real property in one ownership as determined from records maintained by Marin County or the City of Larkspur.

“Runoff factor” means the indicator of stormwater generation of a parcel; it is based upon the average ratio of impervious area to total parcel area for a particular land use category.

“Standard runoff unit (RU)” means the average estimated amount of impervious area of parcels in the single-family residential land use category; it is the product of the average single-family residential parcel size multiplied by the runoff factor for single-family residential parcels:

7,500 sq. ft. × .4 = 3,000 sq. ft.

“Storm drainage system” includes but is not limited to those stormwater drainage conveyance facilities within the City by which stormwater may be conveyed to waters of the United States, including any roads with drainage systems, municipal streets, catch basins, curbs, gutters, ditches, manmade channels or storm drains, which are not part of a publicly owned treatment works (POTW) as defined at 40 C.F.R. 403.3. Storm drainage system also includes “storm drains” as defined in Larkspur Municipal Code Section 9.11.030. (Ord. 1030 § 2(3), 2018; Ord. 1005 §§ 1, 8, 2015; Ord. 871 § 1 (part), 1995. Formerly 15.50.030)