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Drainage Maintenance Standards For Commercial and Multifamily Drainage Facilities is provided in Adobe Acrobat format for compatibility with a wide variety of browsers and computer systems. For help with Acrobat, please see our Adobe Acrobat help page.

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Cover of Drainage Maintenance Standards

This Guide was developed as part of King County's pilot self-certification program for Stormwater Drainage Facilities. The intended audiences are property owners, developers, engineers, or field crews overseeing, specifying, or conducting the maintenance on commercial and multifamily drainage facilities.

This pamphlet, along with the Maintenance Checklist for Commercial and Multifamily Drainage Facilities, Instructions for Stormwater Facility Maintenance Inspections and Tips for Successful Drainage Facility Self-Inspection for use while performing the actual inspections of multifamily or commercial drainage facilities, were developed to help developers, builders, and property owners better understand the rules and regulations. It was written in non-technical language to help the layperson understand the basics of the drainage system constructed on their property, and the associated maintenance needed.

The guide contains typical facility sketches, descriptions of maintenance defects, and descriptions of the maintenance necessary to bring a facility up to standard.

Appendix A of the 2009 King County Surface Water Design Manual also contains information on maintenance standards for drainage facilities, but it is presented in a more formal manner.

For questions about the stormwater website, please contact Blair Scott, Water Quality Planner, King County Stormwater Services Section.