[1]
Code reviser's note: Ord. 934 recodified former chapter 16.08 DMMC under this chapter.
The purpose of the surface water management program (SWM) is to control and prevent flooding, erosion, sedimentation, and water quality degradation; to protect the stream ways and wetlands within the city limits; to accommodate future urban growth and correct existing surface water problems; and to safeguard public safety, prevent property damage, and improve water quality.
(Ord. 832 § 1, 1989)
The Des Moines SWM shall be self-supporting and shall be funded by service charges, grants, and loans; except from time to time the city council may direct transfer of funds to SWM from other city sources.
(Ord. 832 § 3, 1989)
The program established in this chapter shall be administered by the Des Moines public works department, surface water management division. The city manager and the public works director or their designee(s) are authorized to establish further rules, regulations and procedures to implement, administer and enforce this title.
(Ord. 1211 § 1, 1998)
(1) 
The King County Stormwater Pollution Prevention Manual is adopted by reference pursuant to RCW 35A.12.140 as though fully set forth in this chapter, as presently constituted or as it may be subsequently amended. Not less than one copy of this manual, suitably marked to indicate amendments and additions, is filed in the office of the Des Moines City Clerk for public inspection.
(2) 
The King County Surface Water Design Manual is adopted by reference pursuant to RCW 35.21.180 as though fully set forth in this chapter, as presently constituted or as it may be subsequently amended. Not less than one copy of this manual, suitably marked to indicate amendments and additions, is filed in the office of the Des Moines City Clerk for public inspection.
(Ord. 1593 § 1, 2014; Ord. 1671 § 1, 2017)
(1) 
Purpose. The purpose of this chapter is to supplement the King County Surface Water Design Manual, adopted by reference in DMMC § 16.10.350, as the City storm water standards.
(2) 
Soil Quality Preservation. Reference 4-A of the King County Surface Water Design Manual as previously adopted in DMMC § 16.10.350 requires that any areas that have been cleared and graded shall have the soil moisture-holding capacity restored to the original undisturbed soil condition to the maximum extent practicable. This reference shall be applicable to the standards of performance for land grading under DMMC § 14.20.150(3).
(3) 
Drainage Review. A person who clears, grades or otherwise disturbs a site shall provide erosion and sediment control that prevents, to the maximum extent practicable, the transport of sediment from the site to drainage facilities, water resources, and adjacent properties. Erosion and sediment controls shall be applied as specified by the erosion and sediment control measures and performance criteria in the King County Surface Water Design Manual. Drainage review will be made for erosion and sedimentation control for all land filling, clearing and grading permits required under chapter 14.20 DMMC.
(4) 
Storm Water Discharges to Wetlands.
(a) 
Applicability. The requirements below apply only to projects whose storm water discharges into a wetland, either directly or indirectly through a conveyance system, using the thresholds as applied by the King County Surface Water Design Manual.
(b) 
Discharges to wetlands shall maintain the hydrologic conditions, hydrophytic vegetation, and substrate characteristics necessary to support existing and designated uses. The hydrologic analysis shall use the existing land cover condition to determine the existing hydrologic conditions unless directed other-wise by a regulatory agency with jurisdiction. A wetland can be considered for hydrologic modification and/or storm water treatment in accordance with Guide Sheets 1B and 2B in Appendix I-D of the Department of Ecology Stormwater Management Manual for Western Washington. Guide Sheets 1B and 2B of Appendix I-D of the Department of Ecology Stormwater Management Manual for Western Washington are adopted by reference in subsection (5) of this section and are for wetland protection in accordance to this chapter.
(5) 
Department of Ecology Stormwater Management Manual for Western Washington Guide Sheets 1B and 2B – Adopted by Reference.
(a) 
The Department of Ecology Stormwater Management Manual for Western Washington Guide Sheets 1B and 2B are adopted by reference pursuant to RCW 35A.12.140 as though fully set forth in this chapter, and as presently constituted or as may be subsequently amended.
(b) 
Not less than one copy of each such regulation as written, and suitably marked to indicate amendments and additions, is filed in the office of the Des Moines City Clerk and is available for use and examination by the public.
(Ord. 1593 § 2, 2014; Ord. 1671 § 2, 2017)