King County Ditch Maintenance Toolkit

Roadside ditch maintenance is often an overlooked and underfunded aspect of a stormwater management program. Herrera worked with King County to conduct a literature review of 39 local and national ditch maintenance resources to identify ditch maintenance practices, the impact of these practices on flow control and water quality, and prioritization strategies for adopting these practices. Due to the limited information found in the literature review, the project team relied on the County Roads crews and the regional road maintenance group (ROADMAP) to provide input throughout the development of project deliverables.

A desktop assessment and field evaluation of 23 ditches in King County was also conducted. The information gathered from this assessment and evaluation, along with the literature review, was used to develop content for a Field Guide for Roadside Ditch Maintenance. This consists of a set of eight fact sheets, a ditch maintenance matrix, and a set of electronic checklists (Survey 123) for field data collection. The Field Guide, and associated ditch maintenance matrix, is intended to be used by field staff and provides a user-friendly set of recommendations for each of the routine and corrective maintenance activities identified as part of this project.

The Field Guide can be used as a stand-alone document or can be integrated into an existing standard operating procedure (SOP) or operations and maintenance (O&M) manual. A series of eight graphical fact sheets were also developed to cover topics of interest to office-based staff and/or field crews. The final toolkit can be downloaded from King County’s website.