HomeMy WebLinkAboutI Line - MEF - Renton - Final Signed
November 2025
ADA Maximum Extent Feasible
Report - Renton
King County Metro Transit
Project Engineer City of Renton Approval
11/11/2025
DEVELOPMENT ENGINEERING
msippo 12/03/2025
King County Metro (KCM) Transit
Janine Robinson, KCM Project Manager
Ian Kowalski, KCM Line Lead
Kale Chang Yuen, KCM Project Engineer
Consultant Team
Stephanie Forman, Lead Civil Engineer, Forman Consulting Services
Angela Villar, Renton Civil Lead
Other Publication Information
Jacobs Project Number: W3X86400
Project Locations: Auburn, WA; Kent, WA; Renton, WA
i ADA Maximum Extent Feasible Report - Kent
Contents
1 Introduction .............................................................................. 1
1.1 Purpose of the Maximum Extent Feasible ................................. 1
1.2 Project Description ................................................................... 1
2 Existing Pedestrian Facilities ..................................................... 3
2.1 Intersection #1: 108th Ave SE (SR 515) & SE 108th St ............ 3
3 Pedestrian Design Standards .................................................... 5
3.1 City of Renton Standards .......................................................... 5
3.2 Public Right-of-Way Accessibility Guidelines (PROWAG) .......... 5
3.3 WSDOT Design Standards ......................................................... 5
4 Proposed Pedestrian Facilities - MEF ......................................... 6
4.1 Intersection #1: 108th Ave SE (SR 515) & SE 186th St ............ 6
Appendix A: Curb Ramp Geometrics .................................................. 1
186th
ii ADA Maximum Extent Feasible Report - Kent
Acronyms and Abbreviations
ADA Americans with Disabilities Act
BRT Bus Rapid Transit
KCM King County Metro
MEF Maximum Extent Feasible
NE Northeast
NW Northwest
SE Southeast
SR State Route
SW Southwest
WSDOT Washington State Department of Transportation
1 ADA Maximum Extent Feasible Report - Kent
1 Introduction
1.1 Purpose of the Maximum Extent Feasible
1.2 Project Description
The RapidRide I Line Project (Project) will be a 17-mile north-south bus rapid transit
(BRT) service that travels between the Renton Transit Center and the Auburn Transit
Center by the Kent Transit Center, connecting three of the largest suburban cities in
south King County: Renton, Kent, and Auburn. All three communities include regionally
designated Growth Centers, and include the locally identified centers of East Hill, Panther
Lake, and Benson. The corridor includes multiple areas of high concentrations of
population and employment and the suburbs of Renton, Kent, and Auburn are some of
the largest and most diverse in the Seattle area. Connections to other regional high-
capacity transit such as RapidRide F Line, Sounder Commuter Rail, and future Metro and
Sound Transit BRT will provide increased access to regional destinations. Figure 1-1
shows the RapidRide I Line routing and station locations.
The purpose of this ADA Maximum Extent Feasible (MEF) report is to document the
occasional case where due to the nature of the existing roadway facility and built
environment it is impossible for the proposed intersection curb ramps to fully comply
with applicable accessibility standards. The MEF applies throughout the I Line project
and portions of the route are located on state route facilities. Because the state routes
are WSDOT managed access, the MEF will be approved by the City of Renton and
provided to WSDOT for documentation purposes. As shown on Figure 1-1, the RapidRide
I Line route is located on Washington State Department of Transportation (WSDOT)
State Route (SR) facilities in the following areas:
Benson Drive S (SR 515) between I-405 I/C and Talbot Rd S
108th Ave SE (SR 515) between Se 180th St and SE 192nd St
Within the RapidRide I Line project limits and along State Routes located within the City
of Renton, there is one intersection where the proposed improvements trigger MEF
documentation, as shown on Figure 1-1.
2 ADA Maximum Extent Feasible Report - Kent
Figure 1-1: RapidRide I Line – Renton MEF Overview
3 ADA Maximum Extent Feasible Report - Kent
2 Existing Pedestrian Facilities
The project is upgrading ADA accessibility at eleven intersections within the City of
Renton limits. Of those eleven intersections only two are located on a State Route. Of
those intersections located on State Routes, there is only one intersection where current
ADA accessibility design guidelines cannot be met. This location is 108th Ave SE (SR
515) & SE 186th St (NW, NE, and SW Corners).
A summary of the existing conditions at this intersection is provided in the following
subsection.
2.1 Intersection #1: 108th Ave SE (SR 515) & SE 186th St
The I Line project has scope on the northwest corner of 108th Ave SE (SR 515) at the
unsignalized intersection with SE 186th St where a new BRT station is proposed and the
curb return is realigned. Additionally, due to the curb ramp replacement on the
northwest corner, the project is also upgrading curb ramps on the northeast and
southwest corners of the intersection. Within the project scope limits, there are three
existing curb ramps – one located on each of the impacted corners. None of these
existing curb ramps meet current ADA standards. There is also an existing curb ramp
located on the southeast corner of the intersection.
Pedestrians can legally cross this intersection via the four existing curb ramps and there
are no marked crosswalks.
4 ADA Maximum Extent Feasible Report - Kent
Figure 2-1: 108th Ave SE (SR 515) & SE 186th St Existing Conditions
5 ADA Maximum Extent Feasible Report - Kent
3 Pedestrian Design Standards
3.1 City of Renton Standards
City of Renton Standard Plan 130 Policy for Minor Modifications to Signal Systems at
Pedestrian Street Crossings (May 2014) provides guidance on ramp and landing
improvements. “The City will construct other signal upgrades including APS
improvements, and ramp and landing improvements at signalized intersections in
compliance with The 2005 Draft Public Rights of Way Accessibility Guidelines as may be
amended or replaced and adopted by the Department of Justice (PROWAG) in
accordance with its Transition Plan.”
The City of Renton adopted Americans with Disabilities Act (ADA) Transition Plan
(December 2021) which reviewed City policies and standards against the PROWAG 2011.
3.2 Public Right-of-Way Accessibility Guidelines (PROWAG)
The US Access Board publishes guidelines under the ADA that address access to
sidewalks, streets, crosswalks, curb ramps, and other components of public right of way.
For pedestrian access routes PROWAG states, “At an intersection corner, one curb
ramp or blended transition shall be provided for each crosswalk, or a single blended
transition that spans all crosswalks at the intersection corner may be provided,”
(PROWAG, R203.6.1.1 Crosswalks at an Intersection, July 2024).
In the same section, PROWAG also acknowledges the exception where existing physical
constraints make compliance with R203.6.1.1 technically infeasible, a single curb ramp
shall be permitted at the apex of the intersection corner.
3.3 WSDOT Design Standards
WSDOT Design Manual M 22-01.23 Chapter 1510 (September 2024) provides
accessibility criteria for the design of pedestrian facilities to meet state and federal
standards. For work within managed access inside an incorporated City, the City has
jurisdiction beyond the curbs. The pedestrian facilities are to be designed using the City
design standards and the most current ADA requirements, and the public agency
sponsoring the project is responsible for ensuring ADA compliance is addressed on its
project.
For the design of curb ramps, per WSDOT DM 1510.08 (September 2024) “there needs
to be a curb ramp oriented in each direction of pedestrian travel within the width of the
crosswalk it serves to the maximum extent feasible.”
6 ADA Maximum Extent Feasible Report - Kent
4 Proposed Pedestrian Facilities - MEF
The project’s ADA improvements have been designed to meet all pedestrian design
standards to the maximum extent feasible. All ADA slope and dimension requirements
are met for all proposed curb ramps within the City of Renton. However, not all curb
returns provide a separate curb ramp for each direction of pedestrian travel. Below is a
summary of the project’s proposed curb ramps that do not meet full ADA requirements
due to existing physical constraints.
4.1 Intersection #1: 108th Ave SE (SR 515) & SE 186th St
The project is installing one curb ramp on each of the NW, NE, and SW corners of the
intersection. All curb ramps meet ADA dimension and slope requirements on all portions
of the curb ramps.
NW Corner: The proposed design matches the existing condition of a single ramp and
there are existing constraints which prohibit installing two curb ramps on the NW corner
of the intersection. These existing constraints include: roadway slope along the west leg
of SE 186th St, sloped grading behind the sidewalk to the existing property, and potential
conflicts with the existing fire hydrant to remain in the sidewalk. Adding a second ramp
to this corner would also result in impacts to the placement of the proposed bus stop
improvements along 108th Ave SE, causing the station to shift further north and create
greater impacts to the existing private property.
NE Corner: The proposed design matches the existing condition of a single ramp and
there are existing constraints which prohibit installing two curb ramps on the NE corner
of the intersection. These existing constraints include: matching the existing curb radius
to not impede vehicular turning movements, extension of the sidewalk along the east leg
of SE 186th St, and impacts to the existing landscaping and wood fence behind the
existing sidewalk. Adding a second ramp to this corner would result in an expansion of
the sidewalk footprint with additional impacts to the adjacent private property, which is
beyond the scope of the project.
SW Corner: The proposed design matches the existing condition of a single ramp and
there are existing constraints which prohibit installing two curb ramps on the SW corner
of the intersection. These existing constraints include: matching the existing curb radius
to not impede vehicular turning movements. Adding a second ramp to this corner would
result in expansion of the sidewalk footprint, which is beyond the scope of the project.
7 ADA Maximum Extent Feasible Report - Kent
Figure 4-1: 108th Ave SE (SR 515) & SE 186th St Proposed Design
Appendix A: Curb Ramp Geometrics
I Line: Renton Ad-Ready
Curb Ramp Geometrics
DM 1510.09(2)
(a) Width /
Cross Slope
(b) Length /
Running Slope Gutter Slope Counter Slope
(c) Width /
Cross Slope
(d) Length /
Running Slope
(e) Length /
Running Slope
(f) Width /
Cross Slope
(h) Length /
Running Slope
(i) Width / Cross
Slope
4' min/2%15' max/8.3%(j) Lt.(k) Rt.(g)(m) 5% max 4' min/2%4' min/2%15' max/8.3%4' min/2%15' max/8.3%4' min/2%
Cross slope
2% to 5%
10% to
16.7%
10% to
16.7%
Cross slope 2%
to 5%
Existing ----2.9% 2.2%7.2'/2.5%5.5'/1.4%Curb Curb 7.3'/8.5%6.1'/0.3%
Proposed ----0.25% 2.0%6.0'/1.50%5.0'/0.25%----
Existing ----1.00%2.5%5.3'/0.7%5.1'/4.7%6.7'/6.5%5.3'/5.1%6.9'/7.5%5.0'/4.4%
Proposed ----0.20%2.92%6.16'/0.24%8.00'/1.50%8.22'/6.96%8.00'/1.50%8.54'/7.17%8.00'/1.50%
Existing ----0.10%4.7%5.1'/1.0%5.8'/2.4%5.6'/6.7%5.9'/2.4%7.5'/6.3%5.8'/1.8%
Proposed ----0.90%1.75%6.16'/0.95%8.00'/1.50%8.02'/6.40%8.00'/1.50%10.14'/7.11%8.00'/1.50%
Existing 3.1'/0.8%4.0'/10.1%10.80%10.20%0.80%5.90%3.1'/1.0%1.7'/11.1%----
Proposed ----0.98%3.44%6.64'/1.51%8.00'/1.50%11.39'/6.96%8.00'/1.50%Curb Curb
Existing ------------
Proposed ----0.40%3.76%6.64'/0.53%8.00'/1.50%Curb Curb 10.59'/6.78%8.00'/1.50%
Existing ------------
Proposed ----0.44%5.00%6.61'/0.51%8.00'/1.50%9.82'/6.75%8.00'/1.50%7.83'/5.96%8.00'/1.50%
Existing 2.4'/2.8%6.0'/8.7%13.60%10.30%2.80%6.50%------
Proposed ----0.44%4.55%6.61'/0.67%8.00'/1.50%7.83'/7.08%8.00'/1.50%7.66'/7.41%7.25-8.00'/1.50%
Existing 2.9'/1.8%5.2'/8.2%9.40%13.10%1.80%2.80%3.1'/0.5%0.8'/2.7%----
Proposed ----1.75%1.50%5.97'/1.75%6.00'/1.81%7.08'/4.49%6.00'/1.81%8.60'/7.21%6.00'/1.51%
Existing 2.8'/3.4%4.9'/8.4%7.90%13.10%3.40%3.00%2.9'/3.2%3.4'/1.1%----
Proposed ----1.75%4.80%5.97'/1.75%6.00'/1.71%5.56'/5.65%6.00'/1.71%10.23'/7.40%6.00'/1.39%
Existing ----1.70%0.60%3.1'/1.8%6.0'/9.6%3.4'/13.3%5.9'/9.5%3.4'/10.3%6.0'/4.0%
Proposed 5.00'/0.27%7.52'/7.75%Curb Curb 0.27%0.32%5.00'/0.34%5.50'/1.80%----
Existing ------------
Proposed 5.00'/1.32%8.00'/7.61%Curb Curb 1.32%0.43%5.00'/1.72%4.00'/1.99%----
1
1
2
Sheet 1C6.02 - S Grady Way & Shattuck Ave S
Note:
4
1
3
2
Sheet 1C6.04 - S Grady Way & Talbot Rd S
4
Note:
1
Note:
2
Note: Existing parallel curb ramp not in survey. Existing contours were used to determine some of the information.
Note: Existing parallel curb ramp not in survey
Note: No existing curb ramp
Note:
Note:
Sheet 1C6.03 - S Grady Way & Talbot Rd S
Note: Median island to be reconstructed by Sound Transit.
Sheet 1C6.01 - S Grady Way & Lake Ave S
Parallel Ramp - Right
DM 1510.05(2)
3
We
Flare Slopes
10% max
Landing Parallel Ramp - Left Perpendicular Curb Ramp
Existing 2.8'/2.2%3.8'/13.6%--2.20%0.70%2.8'/0.8%1.3'/6.3%----
Proposed 5.00'/1.30%8.00'/7.89%Curb Curb 1.30%0.75%5.00'/2.00%4.00'/1.44%----
Existing 5.0'/0.7%4.2'/10.8%5.40%8.00%0.60%3.20%5.0'/0.7%4.0'/5.9%----
Proposed 5.0'/1.68%7.47'/7.48%6.48%8.67%1.68%2.50%5.00'/1.40%5.00'/1.50%----
Existing 5.1'/1.0%4.2'/7.4%7.80%4.00%1.20%4.00%5.1'/1.3%3.4'/4.1%----
Proposed 5.0'/1.71%6.97'/7.50%8.70%6.45%1.71%0.40%5.00'/1.50%5.00'/1.49%----
Existing 2.9'/5.7%5.0'/7.9%16.60%8.10%4.50%2.30%0.9'/8.1%2.9'/5.7% ----
Proposed ----1.10%2.81%6.06'/1.55%6.00'/1.50%Curb Curb 6.21'/2.77%6.0'/1.50%
Existing ------------
Proposed ----1.00%2.60%6.77'/1.32%8.00'/1.50%7.94'/2.91%8.00'/1.50%Curb Curb
Existing 4.9'/0.8%4.3'/8.6%5.80%5.80%0.80%3.50%4.9'/0.5%4.7'/2.6%----
Proposed ----1.10%0.71%8.00'/1.62%5.00'/0.80%----
Existing ----2.50%0.40%4.9'/0.4%5.9'/2.6%6.9'/7.3%5.9'/1.9%8.0'/5.9%5.9'/2.3%
Proposed ----0.76%1.36%5.00'/0.76%7.50'/1.50%9.19'/6.20%7.50'/1.50%6.50'/6.94%7.50'/1.50%
Existing ----2.50%2.00%5.0'/2.5%5.9'/3.3%8.6'/5.9%5.9'/3.5%8.3'/4.4%5.9'/3.3%
Proposed ----0.76%1.67%6.13'/0.91%6.00'/1.50%8.85'/7.07%6.00'/1.50%7.38'/7.35%6.00'/1.50%
Median Corner Existing 5.1'/1.2%5.9'/7.2%--1.20%2.40%5.1'/0.2%6.1'/1.4%----
SW Corner Existing ----0.10%0.10%5.0'/0.10%5.7'/4.1%--6.1'/4.0%5.7'/4.1%
Existing 2.8'/7.3% 4.8'/7.3% 11.80% 3.80% 6.40% 2.90% 2.8'/8.1%, 1.0'/8.4% - - - -
Proposed ----1.70%0.20%6.16'/1.72%7.00'/1.49%10.33'/7.59%7.00'/1.25%7.32'/2.72%7.00'/1.49%
Existing 3.4'/10.4%6.2'/7.1%15.10%6.20%6.20%7.30%------
Proposed 5.03'/1.5%4.92'/1.02%7.12%1.09%1.50%3.90%5.03'/1.80%5.00'/1.50%----
Existing ------------
Proposed ----0.60%2.50%5.00'/0.60%5.14'/1.66%8.00'/7.50%5.14'/1.66%--
Existing ------------
Proposed ----1.28%2.08%5.00'/1.28%8.00'/1.50%--6.00'/7.05%8.00'/1.50%
Note: No existing curb ramp
3
Note:
1
Note: Existing opening in median island to remain.
1
Note:
2
Note:
1
Sheet 1C6.05 - Talbot Rd S
Sheet 1C6.06 - Talbot Rd S
Sheet 1C6.07 - Talbot Rd S
`
2
Note: No existing curb ramp
Sheet 1C6.08 - Talbot Rd S & S Renton Village Pl
Sheet 1C6.09 - Talbot Rd S & S 23rd St
Sheet 1C6.10 - Talbot Rd S & S 32nd St
2
Note:
1
Note:
2
1
Note:
Note: Existing companion curb ramp for Curb Ramp 2. No linework for existing curb ramp. Existing contour was evaluated to determine existing information as best as possible, some slopes and dimensions could not be provided due to quality of contours.
Note: Existing companion curb ramp for Curb Ramp 1
2
Note: No existing companion curb ramp, since no sidewalk at NW corner.
1
Note: No existing curb ramp
NE Corner Existing - - - - 1.90% 0.10% 5.3'/1.9% 4.9'/1.4% 6.4'/4.8% 4.9'/1.4% 15.4'/9.7% 4.9'/1.2%
Existing ------------
Proposed ----1.00%2.80%5.00'/1.98%5.00'/1.00%----
Existing ------------
Proposed ----0.51%0.50%5.00'/1.50%4.00/1.02%----
Existing ------------
Proposed ----0.92%2.22%5.00'/0.92%6.00'/1.50%6.00'/7.41%5.00'/1.50%--
Existing 3.0'/1.8%4.8'/6.0%17.20%9.80%1.80%5.60%------
Proposed ----1.50%2.73%9.46'/1.53%6.50'/1.53%11.80'/7.64%6.50'/1.48%--
Existing ----0.70%2.00%2.5'/2.0%5.0'/8.5%2.6'/14.8%5.0'/8.5%4.9'/9.7%4.9'/7.7%
Proposed ----1.30%3.36%7.58'/1.30%8.00'/1.60%8.96'/6.58%8.00'/1.60%8.96'/7.50%8.00'/1.42%
Existing ----2.30%2.70%2.6'/4.3%5.0'/9.7% 2.9'/16.0%5.0'/9.7%5.0'/4.7%4.8'/8.8%
Proposed ----1.56%2.22%6.43'/1.56%5.00'/1.70%13.96'/7.40%5.00'/1.52%7.57'/3.24%5.00'/1.70%
Existing ----0.60%3.90%5.0'/0.6%5.0'/2.2%6.4'/4.9%5.0'/1.9%7.4'/7.6%5.0'/2.8%
Proposed ------------
Existing ---1.00%5.40%5.3'/1.0%4.9'/1.4% 4.1'/5.7%5.0'/1.5%5.8'/6.7%4.9'/1.4%
Proposed ------------
Existing 3.1'/8.8%5.9'/9.2%14.40%1.50%6.70%3.20%3.1'/10.4%4'/2.5%----
Proposed ----0.80%2.56%6.31'/1.80%6.56'/0.89%14.65'/8.00%6.56'/0.65%6.38'/2.04%6.56'/0.89%
Existing ----1.50%2.00%3.9'/2.8%6.1'/7.5%4.9'/3.7%5.9'/7.1%4.4'/9.9%6.1'/7.5%
Proposed ----1.80%1.69%5.00'/1.80%5.50'/1.19%7.00'/4.84%5.50'/1.45%12.00'/7.95%5.50'/1.62%
Existing ----4.20%6.70%2.9'/4.7%5.9'/8.9%4.9'/11.8%5.9'/8.9%5.3'/4.6%5.9'/8.6%
Proposed ----0.40%2.84%6.04'/0.40%5.50'/1.57%6.69'/7.97%5.50'/1.57%11.59'/7.96%5.50'/1.51%
Existing ------------
Proposed ----1.90%2.04%5.00'/1.90%7.00'/1.33%6.00'/4.95%7.00'/1.33%9.50'/7.44%7.00'/1.39%
Existing 4.0'/11.5%5.6'/12.0% 3.90%22.00%8.30%4.50%N/A N/A ----
Proposed ----1.50%3.22%12.62'/1.50%5.97'/1.00%8.10'/1.87%5.97'/1.00%8.59'/8.07%5.97'/1.00%
Note: No existing curb ramp
1
Note: No existing curb ramp
2
Sheet 1C6.11 - Talbot Rd S & S 37th St
Note: Existing Companion Curb Ramp for Curb Ramp 2
Sheet 1C6.13 - Talbot Rd S & S 38th CT
1
Note:
2
Sheet 1C6.14 - Talbot Rd S
Note: No existing curb ramp
1
Note: No existing curb ramp
2
Note:
Sheet 1C6.12 - Talbot Rd S & S 37th St
Note: No existing curb ramp
Sheet 1C6.15 - SE Carr Rd & 105th PL SE
1
Note:
2
3
1
Note: Reviewed with City, City okay with existing ramp.
2
Sheet 1C6.16 - SE 180TH ST
1
Note:
4
Note: Reviewed with City, City okay with existing ramp.
Note:
Existing 3.3'/1.1%5.3'/9.2%11.70%11.90%1.10%13.10%N/A N/A ----
Proposed 5.02'/1.30%5.32'/7.92%8.61%7.34%1.30%1.61%5.02'/1.40%4.00'/1.83%----
Existing ----3.30%5.10%3.2'/3.3%4.9'/9.7% 2.9'/15.3%4.9'/9.6%3.0'/9.3%4.9'/9.7%
Proposed 5.00'/1.70%6.00'/7.63%8.84%5.26%1.70%4.92%5.00'/1.42%4.00'/1.52%----
Existing ------------
Proposed ----3.31%2.37%5.00'/3.31%5.00'/1.50%5.00'/6.55%5.00'/1.50%12.00'/7.40%5.00'/1.50%
Existing ------------
Proposed ----3.38%2.22%5.00'/3.38%5.00'/1.50%12.00'/7.50%5.00'/1.50%5.00'/6.61%5.00'/1.50%
Existing ----5.60%0.80%3.0'/6.8%4.3'/11.8%3.0'/17.4%4.3'/11.8%3.3'/4.8%4.3'/9.7%
Proposed 5.00'/1.91%6.48'/7.50%9.22%2.24%1.50%0.41%5.00'/1.91%4.00'/1.50%----
Existing ----0.60%5.30%4.4'/0.6%4.8'/11.2%3.0'/11.4%4.8'/9.7%3.4'/12.2%4.8'/11.2%
Proposed ----0.15%4.50%6.04'/0.38%5.00'/1.35%8.10'/7.92%5.00'/1.16%7.61'/7.18%5.00'/1.35%
Existing ----3.20%1.98%3.2'/4.4%4.8'/10.9%2.8'/9.1%4.8'/10.0%3.3'/16.0%4.8'/10.9%
Proposed ----1.60%1.89%5.94'/1.60%5.00'/1.90%7.03'/3.48%5.00'/1.90%14.78'/7.11%5.00'/1.65%
All curb ramps have detectable warning surfaces
Proposed Feature Does Not Meet Guidelines
If you have employed one of the following provisions highlight to match.
Per DM Section 1510.05(2) - Within the construction impact zone of an alteration project that does not include
reconstruction, realignment, or widening of the roadway, document the following deficient elements in the DDP:
- Perpendicular curb ramp or parallel curb ramp landing cross slope that is constrained by the existing roadway gutter
2
Note:
3
Note:
2
Note: No existing curb ramp
Sheet 1C6.18 - 108th Ave SE & SE 186th St
1
Note:
3
Note:
Sheet 1C6.17 - 108th Ave SE
1
Note: No existing curb ramp
Note:
2
Note: