2009 King County Surface Water Design Manual (SWDM)

Pursuant to King County Council adoption of Ordinance 16264, the Department of Natural Resources and Parks adopted a public rule revising the King County Surface Water Design Manual (SWDM). In accordance with King County Code, Chapter 2.98, Rules of County Agencies, this public rule was adopted on January 9, 2009.

The hard copy of the 2009 SWDM is available for purchase at two locations: the Water and Land Resources Division office at 201 S. Jackson Street, 6th floor reception, and the cashier at the Department of Development and Environmental Services at 900 Oakesdale Ave SW, Renton. The manual costs $145 plus tax and can be ordered by calling 206-296-6519 and paying an additional $13 for shipping.

Need a copy of the 2005 SWDM? It is now on sale at the special discounted price of $51 plus tax and shipping. Call 206-296-6519 to order or come to 201 S Jackson Street 6th floor reception and save shipping.

Files are available for download in Adobe Acrobat PDF format.

The entire manual is available for download. One great benefit of having the SWDM as one electronic document is the search function. It is only necessary to take the time to download it once. Save it to your desktop for convenient access.

2009 King County SWDM (18 MB)

Here the SWDM is provided in sections.

This document contains the main body of the SWDM, which includes Chapters 1-6 and the Definitions Section.

2009 SWDM Main Body (7.8 MB)

This next section includes the SWDM Appendices.

Appendix A Maintenance Requirements for Flow Control, Conveyance, and WQ Facilities (140 Kb)

Appendix B Master Drainage Plan Objective, Criteria and Components, and Review Process (25 Kb)

Appendix C Small Project Drainage Requirements (2.2 MB)

Appendix D Erosion and Sediment Control (ESC) Standards (2.2 MB)

The Reference section is the final part of the SWDM. Although some of the materials in this Reference section may have been adopted by administrative rule or by ordinance, the administrative rule that adopted the SWDM has not formally adopted any of the materials in this section.

References (2.3 MB)

2009 Design Manual Errata:

The printed version of the Manual does not include the errata. If you have a printed version of the Manual, you can download the errata from the page linked here.

2009 SWDM Errata

Application of the Manual's targeted protection levels is determined from the following three application maps of King County. The maps are available here to view or download. This pdf format was chosen to allow the user to zoom in and out, pan the map in any direction, and print the map at the best resolution possible. Click the icon below if you need to download Adobe Acrobat.
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Other than the website listed on the maps, the content of the 2009 maps is the same as the 2005 maps.

2009 Flow Control Applications Map, PDF file

2009 Water Quality Applications Map, PDF file

2009 Landslide Hazard Drainage Areas Map, PDF file

SWDM Summary of Changes (14 KB)

SWDM Public Rule (20 KB)

Previous versions: 2005 Design Manual and other archived documents.

2009 Design Manual Drawings:

Standard drawings from the 2009 King County Design Manual can be downloaded individually in AutoCAD DWG format. Additionally the AutoCAD DWG drawings can be downloaded as a single 9.0 Mbyte file or chapters can be downloaded individually.

Select an individual drawing from the drop down list:

Select Drawing to Download CHAPTER 4 Fig 4.2.1.A--Pipe Compaction Designs and Backfill Fig 4.2.1.B--Pipe Anchor Detail Fig 4.2.1.C--Corrugated Metal Pipe Coupling and/or General Pipe Anchor Assembly Fig 4.2.1.D--Debris Barrier (Off Road Right-of-Way) Fig 4.2.1.E--Debris Barrier (In Road Right-of-Way) Fig 4.2.2.A--Pipe/Culvert Discharge Protection Fig 4.2.2.B--Flow Dispersal Trench Fig 4.2.2.C--Alternative Flow Dispersal Trench Fig 4.2.2.D--Gabion Mattress Energy Dissipator Detail ------------------------------------------------------------ CHAPTER 5 Fig 5.3.1.A Typical Detention Pond Fig 5.3.1.B Typical Detention Pond Sections Fig 5.3.1.C Overflow Structure Fig 5.3.1.D Permanent Surface Water Control Pond Sign Fig 5.3.1.E Weir Section for Emergency Overflow Spillway Fig 5.3.2.A Typical Detention Tank Fig 5.3.2.B Detention Tank Access Detail Fig 5.3.3.A Typical Detention Vault Fig 5.3.4.A Flow Restrictor (Tee) Fig 5.3.4.B FLow Restrictor (Baffle) Fig 5.3.4.C Flow Restrictor (Weir) Fig 5.3.4.D Simple Orifice Fig 5.3.4.E Rectangular, Sharp-Crested Weir Fig 5.3.4.F V-Notch, Sharp-Crested Weir Fig 5.3.4.G Sutro Weir Fig 5.3.7.A Simple Detention Pond - Plan View Fig 5.3.7.B Simple Detention Pond - Section Views Fig 5.4.1.A USDA Textural Triangle Fig 5.4.2.A Typical Infiltration Pond Fig 5.4.3.A Typical Infiltration Tank Fig 5.4.6.A Conceptual Small Infiltration Basin ------------------------------------------------------------ CHAPTER 6 Fig 6.2.5.A Flow Splitter, Option A Fig 6.2.5.B Flow Splitter, Option B Fig 6.2.6.A Flow Spreader Option A: Anchored Plate Fig 6.2.6.B Flow Spreader Option B: Concrete Sump Box Fig 6.2.6.C Flow Spreader Option C: Notched Curb Spreader Fig 6.2.6.D Flow Spreader Option D: Through-Curb Port Fig 6.3.1.A Biofiltration Swale Schematic Fig 6.3.1.B Biofiltration Swale Cross-Sections Fig 6.3.1.C Biofiltration Swale Underdrain Detail Fig 6.3.1.D Biofiltration Swale Low-Flow Drain Fig 6.3.1.E Biofiltration Swale Wheel Strips Fig 6.3.4.A Filter Strip Terminology Fig 6.3.4.B Typical Filter Strip Details Fig 6.4.1.B Wetpond Fig 6.4.1.B Wetpond (Continued) Fig 6.4.1.C Waterfowl Signage Fig 6.4.2.A Wetvault Fig 6.4.3.A Stormwater Wetland-Option A Fig 6.4.3.B Stormwater Wetland-Option B Fig 6.4.4.A Combined Detention and Wetpond Fig 6.4.4.A Combined Detention and Wetpond(Continued) Fig 6.4.4.B Alternative Configurations of Detention and Wetpool Areas Fig 6.5.2.A Sand Filter with Level Spreader Fig 6.5.2.A Sand Filter with Level Spreader(Continued) Fig 6.5.2.B Sand Filter with Pretreatment Cell Fig 6.5.2.B Sand Filter with Pretreatment Cell(Continued) Fig 6.5.2.C Schematic of Stepped Side Slopes Fig 6.5.3.A Sand Filter Vault Fig 6.5.3.A Sand Filter Vault(Continued) Fig 6.5.4.A Linear Sand Filter Fig 6.5.5.A Stormfilter, Schematic Fig 6.6.1.A Schematic of Catch Basin Fig 6.6.2.D Baffle Oil/ Water Separator Fig 6.6.2.E Coalescing Plate Oil/Water Separator ------------------------------------------------------------ APPENDIX C Fig C.2.1.A Typical Splash Block Fig C.2.1.B Driveway Application of Dispersion Trench and Rock Pad Fig C.2.1.C 10-Foot Dispersion Trench Cross-Section and Roof Application Fig C.2.1.D 50-Foot Dispersion Trench with Notched Board Fig C.2.1.E Application of Sheet Flow Dispersion Fig C.2.2.A Typical Trench Infiltration System Fig C.2.2.B Alternative Trench Infiltration System Fig C.2.2.C Typical Drywell Infiltration System Fig C.2.2.D Typical Ground Surface Depression Infiltration System Fig C.2.4.A Typical Splashblock for Basic Dispersion Fig C.2.4.B Typical Gravel-Filled Dispersion Trench for Basic Dispersion Fig C.2.4.C Examples of Basic Dispersion for Steep Driveways Fig C.2.4.D Examples of Basic Dispersion for Driveways Fig C.2.5.A Typical Rain Garden (Bioretention Pond) Fig C.2.5.B Typical Rain Garden with Containment Berm Fig C.2.7.A/B Typical Above Ground Other Possible Resdervoir Configurations Fig C.2.8.A Typical Vegetated Roof Cross-Section Fig C.2.11.A Perforated Pipe Connection for a Single Family Residence Fig C.3.1.A Stabilized Construction Entrance Fig C.3.1.B Waterway Installation Fig C.3.1.C Slope Installation Fig C.3.1.D Plastic Covering Fig C.3.1.E Silt Fence Fig C.4.2.A Single Family Residence - Flow Control BMP Site Plan Fig C.4.2.B Single Family Residence - Small Site ESC Plan ------------------------------------------------------------ APPENDIX D Symbol D.3.1.1 Plastic or Metal Fence Symbol D.3.1.2 Stake and Wire Fence Fig D.3.1.A Stake and Wire Fence Fig D.3.2.A Surface Roughing Symbol D.3.2.2 Mulching Symbol D.3.2.3 Nets and Blankets Fig D.3.2.B Waterway Installations Fig D.3.2.C Slope Installations Symbol D.3.2.4 Plastic Covering Fig D.3.2.D Plastic Covering Symbol D.3.2.5 Straw Wattles Fig D.3.2.E Straw Wattles Synbol D.3.2.6 Temporary and Permanent Seeding Symbol D.3.2.7 Sodding Symbol D.3.2.9 Compost Blankets Symbol D.3.3.1 Silt Fence Fig D.3.3.A Silt Fence Fig D.3.3.B Silt Fence Installation by Slicing Symbol D.3.3.2 Brush Barrier Fig D.3.3.C Brush Barrier Symbol D.3.3.3 Vegetated Strip Symbol D.3.3.4 Triangular Silt Dike Symbol D.3.3.5 Compost Berms Symbol D.3.3.6 Compost Socks Symbol D.3.4.1 Stabilized Construction Entrance Fig D.3.4.A Stabilized Construction Entrance Symbol D.3.4.2 Construction Road/Parking Area Stabilization Symbol D.3.4.2 Wheel Wash Fig D.3.4.B Wheel Wash and Paved Construction Entrnace Symbol D.3.5.1 Sediment Trap Fig D.3.5.A Sediment Trap Cross-Section Fig D.3.4.A Sediment Trap Outlet Symbol D.3.5.2 Sediment Pond Fig D.3.5.B Sediment Pond Plan View Fig D.3.5.C Sediment Pond Cross Section Fig D.3.5.D Sediment Pond Riser Detail Symbol D.3.5.3 Storm Drain Inlet Protection, FFP Symbol D.3.5.3 Storm Drain Inlet Protection, CBI Symbol D.3.5.3 Storm Drain Inlet Protection, CBP Fig D.3.5.E Filter Fabric Protection Fig D.3.5.F Catch Basin Insert Fig D.3.5.G Block and Gravel Curb Inlet Protection Fig D.3.5.H Curb and Gutter Barrier Protection Fig D.3.6.A Sketch of Plan of Surface Water Controls Symbol D.3.6.1A Interceptor Dike Symbol D.3.6.1B Interceptor Swale Fig D.3.6.B Interceptor Dike Symbol D.3.6.C Interceptor Swale Symbol D.3.6.2 Pipe Slope Drains Fig D.3.6.D Pipe Slope Drain Symbol D.3.6.4 Ditches Fig D.3.6.E Check Dams - Cross Section Fig D.3.6.E Check Dams - Check Dam Spacing Symbol D.3.6.5 Outlet Protection Symbol D.3.6.6 Level Spreader Fig D.3.6.F Level Spreader - Cross Section Fig D.3.6.F Level Spreader - Detail of Spreader Fig D.7.3.A Sample Small Site ESC Plan

 

Select a group of drawings to download and extract:

Standard Drawings in AutoCAD DWG format Large ZIP file of all chapters OR Download ZIP files of individual chapters: Chapter 4 in AutoCAD format (1.9 MB) Chapter 5 in AutoCAD format (2.0 MB) Chapter 6 in AutoCAD format (3.0 MB) Appendix C in AutoCAD format (1.4 MB) Appendix D in AutoCAD format (863 KB)

1FIG_DWG.ZIP (9.1 MB)