Sunset and Heathfield Pump Stations upgrades

Project library

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• Project updates
• Project drawings
• Planning documents
• Historical planning documents - background information only
• Pump station manuals

Project updates

• No project updates posted at this time.

Project drawings

• Project area (PDF, 368KB)
• South Lake Sammamish Planning Basin (see Attachment 2 of the Project Initiation Document, below)
• As-built drawings
• Pump Stations (.zip file, 73MB)
• Forcemains (.zip file, 20MB)

Planning documents

• Project Initiation Document, March, 2008 (1.43MB, PDF)
  This document consolidates information on the project developed during regional wastewater conveyance system planning. This is the final document produced in project planning. The purpose of the document is to transfer the project from conveyance system planning to the design phase.
• Attachment 1. Project Area
• Attachment 2. South Lake Sammamish Planning Basin
• Attachment 3. Hydraulic Analysis of the Conveyance System Limiting the Sunset Heathfield Capacity Upgrade
• Attachment 4. Tabula Cost Estimate Information
• The Conveyance System Improvement (CSI) Program Update, June 2007, provides the most current information for this project.
  The update identifies projects needed for increasing capacity in the regional wastewater conveyance system to accommodate population growth; and, also provides a status on the County's asset management program for replacing or substantially rehabilitating deteriorated portions of the system. It then lays out a schedule and budget for these projects. The need for the Sunset/Heathfield Project is documented in this report.
• Appendix B, Project Description Summaries (PDF)
• Appendix C, Technical Memorandum-Regional Conveyance System Needs (PDF)
• Main Report (2.2MB, PDF)

Historical planning documents - background information only

The task documents that comprise this report are out of date and should not be relied on for current information.

South Lake Sammamish Report, October 2003 (CSI Program)
This report evaluates the South Sammamish basin. The primary problem in this area is the more than 20,000 feet of large-diameter pipe that will reach capacity within this decade, in some cases causing storm-related surcharging and possible overflows, as well as operations and maintenance issues related to two aging county pump stations. This is also a high growth area. Proposed improvements for this basin include conveyance upgrades, diversions, and projects to attenuate peak flows, such as storage and I/I control.

• Cover, Master Table of Contents, Executive Summary
• Task 210: South Sammamish Basin Planning Summary
• Task 220: South Sammamish Basin Facilities Review
• Task 230: Characterization of South Sammamish Basin Existing Conditions
• Task 240: Wastewater Service Alternative Development
• Task 250: Refining Wastewater Service Alternatives
• Task 260: South Sammamish Basin Task Summary

Pump station manuals

All information from the manuals should be verified before being used for design purposes.

• Operations Manuals
  • Heathfield Pump Station Operations Manual, Review draft, December 2004 (2.4MB, PDF)
  • Sunset Pump Station Operations Manual, Review draft, December 2004 (2.7MB, PDF)
• Offsite Facilities and Miscellaneouse Structures Manual
  • Heathfield Pump Station (Pages 1-39 to 1-48, 2.7MB, PDF)
    • See Updates (PDF)
  • Sunset Pump Station (Pages 1-153 to 1-162, 3.0MB, PDF)