Kennydale Lakeline Sewer System Assessment Project
Last updated: August 7, 2017
Frequently Asked Questions
What is the goal of this project?
Where is the Kennydale lakeline?
What components does the Kennydale Lakeline Sewer System include?
How does the Kennydale Lakeline Sewer System work?
How old is the Kennydale Lakeline Sewer System?
What process is the City using to assess the lakeline’s condition?
What did the City accomplish during Phase 1?
What will the City do during Phase 2?
What repair or replacement options are being considered?
What will it cost to repair or replace the lakeline?
How will the City pay for lakeline repairs? Will my rates go up?
Who can I contact for more information?
What is the goal of this project?
The Kennydale Lakeline Sewer System is aging and may need to be repaired or replaced to ensure long-term service. In 2016, the City of Renton hired a consultant team to evaluate the condition of the lakeline system. Condition assessment results will inform an alternatives evaluation process to determine the best way to repair or replace the lakeline.
Where is the Kennydale lakeline?
The lakeline extends along portions of Lake Washington Drive N and Mountain View Avenue NE. See project location map.
What components does the Kennydale Lakeline Sewer System include?
The lakeline system consists of the 8-inch lakeline (in-lake portion), 8-inch shoreline (out-of-lake portion), 6-inch service laterals that convey sewage from homes to the lakeline, lateral cleanouts, lateral isolation valves, the Lake Washington Flush Station, the Lake Washington No. 2 Lift Station, and a 6-inch forcemain. The total length of the 8-inch lakeline is approximately 4,800 feet. There are 33 lateral connections serving approximately 55 homes.
How does the Kennydale Lakeline Sewer System work?
The lakeline system collects sewage from lakefront residences and conveys flow to the lift station at the north end of the line, where it is pumped to King County’s Eastside Interceptor. Sewage is conveyed to the lakeline from homes via smaller laterals. More than one home is connected to about a third of the laterals. The flush station, at the southern terminus of the lakeline, is run periodically throughout the day to help convey sewage to the lift station. The flush station was originally intended to move (flush) sewage and solids through the lakeline; however, at this time flushing flows cannot be achieved without risking sewer backups at residences. Therefore, the flush station is run at a lower flow rate that “freshens” the line and helps convey sewage to the lift station.
Sewage from several lakefront homes to the north also discharge to the lift station wet well. Originally, the lift station also collected industrial sewage from Barbee Mill and other lakefront businesses. However,these flows were removed from the lakeline system during redevelopment of the area.
How old is the Kennydale Lakeline Sewer System?
The Kennydale Lakeline Sewer System was originally constructed in 1972 through Local Improvement District 270.
What process is the City using to assess the lakeline’s condition?
The condition assessment will occur in two phases:
Phase 1 – Initial Assessment (September through December 2016) – Complete: Performed initial assessment activities to determine what additional evaluation efforts would be needed to complete a thorough condition assessment in Phase 2.
Phase 2– Condition Assessment(Summer 2017 through 2018): The team will use information gathered during Phase 1 to develop an approach to evaluate the lakeline’s condition more thoroughly. From this detailed assessment, the team will develop alternatives to address service maintenance and reliability in the lakeline system area. Phase 2 will be split into two parts:
- Preliminary Condition Assessment (2017): Perform pilot testing and other activities at priority locations to ensure evaluation approaches will work as anticipated.
- Comprehensive Condition Assessment (2018): Complete technical work for all remaining homes to fully inform the condition assessment.
What did the Cityaccomplish during Phase 1?
The City’s annual cleaning activities in September 2016 initiated Phase 1, when the project team began collecting data on the existing system and evaluatedlakeline conditions, where possible. The City and project team:
- Initiated communication activities with residents connected and adjacent to the lakeline.
- Collected base map and survey information for infrastructure directly related to the routine flushing activities where property owners had granted access for crews.
- Tested the effectiveness of in-water survey methods.
- Characterized the environmental conditions to identify needed permits for future work efforts.
- Evaluated operation and maintenance practices for the lakeline system, and recommended modified or additional practices, where appropriate.
- Conducted a condition assessment of the Lake Washington Flush Station andthe Lake Washington No. 2 Lift Station.
What will the City do during Phase 2?
During Phase 2, the project team will:
- Map the horizontal and vertical location of the entire lakeline system: Mapping will include the mainline pipe, laterals, cleanouts, and valves, as well as nearby docks, bulkheads, and homes.
- Complete a more thorough condition assessment: The team will measure the pipe wall thickness where feasible, analyze the metal for corrosion, and investigate the structural integrity of associated bulkheads.
- Develop a hydraulic model of the lakeline system: The model will help the team better understand how the system currently works and identify options for improving operations and maintenance.
- Obtain local permits needed to conduct near-term condition assessment work.
- Apply for federal, state, and local permits required to conduct more extensive condition assessment work in the future.
What repair or replacement options arebeing considered?
We have not identified options to repair or replace the lakeline yet, because those solutions will depend on what we find during the condition assessment.
What will it cost to repair or replace the lakeline?
We don’t know, as cost estimates will depend on the repair or replacement options we identify. Cost estimates will be prepared as part of the alternatives analysis process.
How will the City pay for lakeline repairs? Will my rates go up?
Any repairs or replacement of the lakeline will be funded through the City’s Wastewater Capital Improvement Program. Any rate increase that may be required will be shared among the entire customer base.
Who can I contact for more information?
Please contact David Christensen at or 425-430-7212.
More information can also be found at: rentonwa.gov/kennydalelakeline/
Kennydale Lakeline Sewer System Assessment ProjectLast Updated: August 7, 2017
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