Lower North Creek Surface Water Management Area

Web Header - North Creek at 240th

Open House Recap 

City of Bothell held a virtual open house from November 16 through December 31, 2020, as well as a community meeting through Zoom on December 17, to share information with the Bothell community about the Lower North Creek Surface Water Management Area (SWMA). The City's Surface Water staff invited feedback about potential strategies for existing, future, and programmatic efforts and activities within the area that would help protect natural resources. 

Response to Community Feedback

Thank you to all who shared feedback with us, either through the online feedback form or during the December 17, 2020 Zoom meeting. Staff appreciate your thoughtful comments and questions. Surface Water staff thoroughly reviewed your feedback and have included responses to those comments and questions that are relevant to this early stage of the planning process. 

Read the responses to your feedback.

LNC Feedback Cover Page

Recording of December 17 Community Meeting

Surface Water staff held a one-hour community meeting through Zoom to provide background information about Bothell's Surface Water Management Areas and to answer questions about proposed strategies and activities aimed at helping protect water quality. Click here to watch a YouTube recording of the December 17, 2020 meeting.

Click to watch recording of Dec. 17, 2020 community meeting

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  1. About Lower North Creek
  2. Possible Efforts and Activities
  3. Data Table for Lower North Creek
  4. Data Dictionary

General and Physical Character

The Lower North Creek SWMA makes up 3.64 square miles with 65.79 percent (2.40 square miles) within City limits.

Very severely erosive soils also classified on steep slopes (>40%) make up 2.53 percent of the SWMA. Compared to other SWMAs, 2.53 percent is the fourth lowest.

The City had a detailed study of this area performed in 2006, titled the North Creek Fish and Wildlife Critical Habitat Protection Area Study. This study delineated and assessed the importance of wetlands, streams, and other critical areas and their contribution to the quality of cool groundwater inputs to North, Palm, and Woods/Cole Creeks.

Land Use and Development

The prominent land use feature of this SWMA is residential with 36.7% of total parcel area with the second highest land use being commercial with 26.6% parcel area.
 
Thirty-three percent of the area is covered by impervious surfaces. Of the impervious area, approximately one-fourth of the area is road surface (pollutant generating).

Natural Environment

The area includes two streams (Palm Creek and Woods/Cole Creek) and an area that drains directly to North Creek. The total stream length within the SWMA is 16.96 miles. Twenty-two percent of the SWMA is mapped as wetlands and associated buffers.
 
The City has assessed habitat and biologic conditions for Lower North Creek at Palm Creek and found it to have the least impaired biological community of all streams in the city, though the creeks are still severely to moderately impaired. All streams in the SWMA are known to have low dissolved oxygen levels and high temperatures and are on Ecology’s 303(d) list for impaired water bodies for fecal coliform.

Stormwater Infrastructure

The amount of total stormwater conveyance is 107 miles (29.39 miles/square mile) with 4,009 catch basins within the SWMA. The SWMA has 26.7 control structures per square mile and 114.4 water quality treatment facilities per square mile.

Surface Water Management Strategies

This SWMA has some of the higher quality basins that support North Creek in Bothell. Staff has selected Lower North Creek as its SMAP high-priority basin. Surface Water efforts will focus on protecting and preserving stream buffers and enhancing stormwater controls to the relatively higher quality creeks in this area.

Click each link below to open the document as a PDF

  1. Aerial Map of Lower North Creek SWMA (PDF)
  2. Characteristics of Lower North Creek SWMA (PDF)
  3. Lower North Creek SWMA Data Table (PDF)
  4. SWMA Data Dictionary and Explanations (PDF)
  5. Map of SWMA Delineation within Bothell (PDF)
  1. Bothell SWMA Descriptions (PDF)
  2. Workflow to Perform Land Use Analysis on SWMAs (PDF)
  3. Storm and Surface Water Master Plan Update, Section 3 - Watershed Management (PDF)
  4. 2021 Storm and Surface Water Master Plan Update (PDF)

Aerial Map of Lower North Creek SWMA (click to open as a PDF)

Lower North Creek SWMA Map

Map of SWMA Delineation within Bothell (click to open as a PDF)

SWMA Map - All