HomeMy WebLinkAboutPN_Project_Narrative_250317_v1Project Narrative – SEPA
Project Name:
Oakesdale Avenue Southwest Storm System Project
Size:
0.15 acres
Location:
Oakesdale Ave SW (from SR900 to SW 3rd Pl).
Land Use Permits Required:
-Civil Construction Permit, City of Renton
Zoning Designation of Site and Adjacent Properties:
Site is City of Renton right-of-way with adjacent properties zoned as Residential 8 du/ac (R8).
Current Use of Site and Any Existing Improvements:
Existing site conditions consist of two‐lane residential streets with asphalt roadway pavement 23 to 34
feet in width and 4‐foot wide concrete sidewalks on the west side of the roadway with curb and gutter
and a vegetated swale on the east side of the street. The opposing cross‐slopes of the asphalt pavement
and concrete sidewalk results in a gutter that directs runoff west along Oakesdale Ave SW to catch
basins and east to the vegetated swale. A high point exists midway along the length of the street as it
curves which divides the project into two small catchments and directs stormwater to the west and to
the south to separate storm structures. The captured runoff from these two small catchments
recombines within the project area. In most areas, private landscaping (grass and shrubs) or driveways
occupy the area between the back of sidewalk and the right‐of‐way line. The proposed project will
maintain the two‐lane residential streets.
Special Site Features: None
Statement Addressing Soil type and Drainage Conditions:
Type of material at site: Urban land-Beausite complex, a typically well-drained gravelly and sandy loam
soil with moderately high to high permeability underlain with sandstone or bedrock. The soil has minor
components of Alderwood and Mckenna soil groups.
Proposed Use of the Site and Scope of the Proposed Development:
The purpose of the Oakesdale Ave SW Storm System Project is to improve conveyance, replace aging
and deteriorated pipes, and improve maintenance access.
The project proposes to install a new 18” stormwater main within the right of way of Oakesdale Ave SW
which allow bypassing and abandonment of existing conveyance pipes which have been shown via CCTV
investigation to be in poor condition. One segment of the existing storm main to be abandoned extends
across the front yard of 301 Oakesdale Ave SW and does not allow access for repair and maintenance.
This abandonment will not have an impact on the property as the pipe can be accessed from manhole
structures upstream and downstream of the pipe. No work on private property requiring any easements
is proposed. All existing collection structures in the project area will be connected to the new
stormwater main extending southwest on Oakesdale Ave SW.
As a part of the project, pedestrian mobility at the intersection of Oakesdale Ave SW and Sunset Blvd
will be improved by replacing segments of uneven and severely cracked sidewalk and replacing two curb
ramps to meet accessibility standards. A half street grind and overlay will be performed per City
standards to restore existing roadway as part of site restoration.
Plat Information: N/A
Access:
Access to site can be achieved from SR 900 or SW 3rd Pl.
Proposed Off-Site Improvements: N/A
Total Estimated Construction Cost/Estimated Fair Market value of Proposed Project:
Total Estimated Construction Cost: $350,000
Estimated Fair Mark Value of Proposed Project: N/A
Estimated Quantities and Type of Materials Involved in Fill or Excavation:
Cut = 380 cubic yards
Fill = 330 cubic yards
Type of material: Urban land-Beausite complex, a typically well-drained gravelly and sandy loam soil
with moderately high to high permeability underlain with sandstone or bedrock.
Number, Type and Size of Any Trees to be Removed:
No trees are being removed as a part of this project.
Explanation of Any Land to be Dedicated to the City:
None
Any Proposed Job Shacks, Sales Trailers, and/or model Homes: N/A
Any Proposed Modifications Being Requested: None
Is Project Within 100 ft of a Stream or Wetland:
No
Is Project within 200 ft of Black River, Cedar River Springbrook Creek, May Creek and Lake
Washington:
No