Surface Water Design Manual
Sponsoring Agency: Department of Natural Resources and Parks / Water and Land Resources Division
Effective Date: April 24, 2016
Approved: /s/ Christie True
Type of Action: Supersedes PUT 8-3-4 (PR)
Signed document (PDF, 202KB)
1.0 SUBJECT TITLE: Surface Water Design Manual
1.1 EFFECTIVE DATE: The effective date of this Public Rule is February 3, 2016, or thirty days after filing with King County Archives and Records Management, whichever comes later.
1.2 TYPE OF ACTION: Superseding PUT 8-3-4 (PR)
1.3 KEY WORDS: (1) Drainage; (2) Permit Review; (3) Design Manual; (4) Stormwater; (5) Low Impact Development; (6) Department of Permitting and Environmental Review.
To adopt the 2016 edition of the Surface Water Design Manual, which is an update to the 2009 Surface Water Design Manual to improve the clarity and cost effectiveness of its requirements and be equivalent with the state's 2014 Stormwater Management Manual for Western Washington.
3.0 ORGANIZATIONS AFFECTED:
3.1 Landowners and residents of unincorporated King County.
3.3 Department of Natural Resources & Parks (DNRP), and its Water and Land Resources Division (WLRD), or their successor agencies.
3.4 Department of Permitting and Environmental Review (DPER).
4.1 King County Code Chapter 9.04 – Surface Water Runoff Policy
4.2 King County Ordinance Nos. 2281, 4938, 9163, 13189, 13190, 13191, 15051, 15052, 15053, 16264, and TBD prior to adoption of this Public Rule.
4.3 King County's National Pollutant Discharge Elimination System (NPDES) Municipal Stormwater Permit.
4.4 King County Code 2.98.
5.1 "Applicant" means a property owner or a public agency or public or private utility that owns a right-of-way or other easement or has been adjudicated the right to such an easement under RCW 8.12.090, or any person or entity designated or named in writing by the property or easement owner to be the applicant, in an application for a development proposal, permit or approval.
5.2 "Development" means any activity that requires a permit or approval, including, but not limited to, a building permit, grading permit, shoreline substantial development permit, conditional use permit, special use permit, zoning variance or reclassification, subdivision, short subdivision, urban planned development, binding site plan, site development permit or right-of-way use permit. "Development" does not include forest management activities, as defined in K.C.C. chapter 21A.06.
5.3 "Drainage" means the collection, conveyance, containment or discharge, or any combination thereof, of surface water or stormwater runoff.
5.4 "Drainage review" means an evaluation by King County staff of a proposed project's compliance with the drainage requirements in the Surface Water Design Manual.
5.5 "Stormwater" means the water produced during precipitation or snowmelt, which runs off, soaks into the ground, or is dissipated through evapotranspiration.
5.6 "Surface Water Design Manual" means the manual, and supporting documentation referenced or incorporated in the manual, describing surface water and stormwater design and analysis requirements, procedures and guidance. The "Surface Water Design Manual" is formally adopted by rule under the procedures in K.C.C. chapter 2.98 and is available from the department of permitting and environmental review or the department of natural resources and parks, water and land resources division, or their successor agencies.
6.1 The Surface Water Design Manual contains the King County surface water and stormwater design and analysis requirements, procedures, and guidance for development applications in unincorporated King County.
6.2 The 2016 edition of the Surface Water Design Manual will be available for reading at https://www.kingcounty.gov/stormwater.
6.3 This Public Rule is exempt from the rule of strict construction and shall be liberally construed to give full effect to the objectives and purposes for which it was adopted.
6.4 If any provision of this Public Rule or its application to any person or property is held invalid, the remainder of the Public Rule or the application of the provision to other persons or property shall not be affected.
7.1 Reviews the Surface Water Design Manual (Manual) and revises it when necessary.
7.2 Determines if a development application is subject to drainage review and thus required to comply with the Manual.
7.3 Prepares drainage plans in compliance with the Manual and submits those drainage plans to the department or division performing drainage review as specified in K.C.C. 9.04.070.
DPER or DNRP, WLRD
7.4 Performs drainage review of the plans submitted by the applicant in Step 7.3.
7.4.1 Works with the applicant to address any Manual compliance issues.
7.4.2 Approves the drainage plans as compliant with the Manual.
7.5 Constructs the drainage improvements required by the approved plans and the Manual and maintains them in accordance with Manual until provisions are made for made for transfer of maintenance responsibility to another entity as specified in the Manual.
8.1 The Department of Natural Resources & Parks, Water and Land Resources Division is responsible for:
8.1.1 Issuing revisions to the Surface Water Design Manual when necessary.
8.1.2 Providing training on the Manual to the general public, developers, and employees of the Department of Permitting and Environmental Review.
8.1.3 Performing drainage review of WLRD surface water and stormwater projects and other government agency linear projects as specified in K.C.C. 9.04.070.
8.2 The Department of Permitting and Environmental Review is responsible for:
8.2.1 Determining if a development application is subject to drainage review and must comply with the Manual.
8.2.2 Performing drainage review of all development projects, except WLRD surface water and stormwater projects and other government agency linear projects as specified in K.C.C. 9.04.070.
8.2.3 Inspecting development construction and sites for compliance with approved drainage plans and the Manual.
8.3 The applicant is responsible, at a minimum, for:
8.3.1 Demonstrating that the development application complies with the Manual.
8.3.2 Constructing the drainage improvements required by the approved plans and the Manual.
8.3.2 Maintaining the drainage improvements required by the approved plans and the Manual until such time as provisions are made for transfer of maintenance responsibility to another entity in accordance with the Manual.
9.1 2016 Surface Water Design Manual Chapters 1, 2, 3, 4, 5, and 6; and Appendices A, B, C, and D.
9.2 2016 Surface Water Design Manual Landslide Hazard Drainage Areas Map.
9.3 2016 Surface Water Design Manual Flow Control Applications Map.
9.4 2016 Surface Water Design Manual Water Quality Applications Map.