Parametrix Technical Memorandum
let's create tomorrow, together
DATE: March 18, 2025
TO: Kay Cheng, WSP
FROM: Andrew Lee, PE, TE, PTOE; traffic analysis excerpted from George Naylor (WSP) SUBJECT: Design Concepts Summary Memo
CC: Carolyn Mamaradlo, SMCTA; Douglas Kim, Town of Atherton PROJECT NUMBER: 474-1585-069
PROJECT NAME: El Camino Real Complete Streets Study
This memorandum summarizes the alternatives development process for the El Camino Real Complete Streets Study ("Study"). The project study area is a 1.5-mile stretch of El Camino Real, which is also designated State Route 82, within and adjacent to the Town of Atherton ("Atherton"); the project extents include a portion of unincorporated San Mateo County, known as North Fair Oaks, and City of Menlo Park ("Menlo Park"). The project's objective is to identify potential modifications to El Camino Real to add multimodal facilities, such as pedestrian facilities, bikeways, transit stop improvements, and ancillary facilities (e.g., stormwater improvements, lighting, safety measures).
The design concept portion of the project scope follows this process:
1. Preliminary alternatives development and screening
2. Conceptual design of screened alternatives and evaluation
3. Selection of a preferred design
The following sections summarize the analysis and conclusions from each step.
1. Existing conditions
The public rights of way along El Camino Real are approximately • 130 feet wide between Selby Lane and Wilburn Avenue.
• 100 feet wide between Wilburn Avenue and Glenwood Avenue/Valparaiso Avenue.
Within the study area, southbound El Camino Real from north of Selby Lane to Alejandra Avenue is within Atherton. This section has three vehicle lanes, partially paved shoulder, no on-street parking, no sidewalks or bike lanes, and no curb and gutter. The segment from Alejandra Avenue to Valparaiso Avenue is within Menlo Park jurisdictional limits and fronts properties in Atherton. This segment has three vehicle lanes which transition to two through lanes and a right turn lane approaching Valparaiso Avenue. Similarly, this segment includes a partially paved shoulder, no on- street parking, no sidewalks or bike lanes, and no curb and gutter except at the Menlo College Drive and Valparaiso Avenue intersections. There are intermittent storm drain inlets on the west side of El Northbound El Camino Real between Glenwood Avenue and Watkins Avenue lies within Menlo Park.
This section predominantly has two vehicle lanes, sidewalks, curb and gutter, and on-street parking that transitions to right turn lanes at intersections. The segment between Watkins Avenue and north of Wilburn Avenue is located within Atherton, has three vehicle lanes, a partially paved shoulder, no X 6001 Shellmound Street, Suite 500 • Emeryville, CA 94608 | 510.343.6400 | Parametrix.com Parametrix Technical Memorandum
on-street parking, no sidewalks or bike lanes, and no curb and gutter. The segment north of Wilburn Avenue is located within North Fair Oaks and retains three vehicle lanes with on-street parking, sidewalk, and curb and gutter.
2. Preliminary alternatives development and screening
The Project team considered the following options for walk, bike, transit, and drive facilities. These preliminary alternatives attempted to account for the corridor conditions identified in Phase 1 that • Collision records, including severe injury and fatal collisions, and designation as a High Injury Corridor.
• Physical conditions that include the lack of dedicated walk, bicycling, and transit facilities. • Planning documents for El Camino Real prepared by the Town of Atherton, adjacent jurisdictions (City of Menlo Park and San Mateo County), and State and regional agencies (Caltrans, Metropolitan Transportation Commission.1
• Travel behaviors that include non-drive travel mode share (8.5%), average daily traffic volumes (36,000 vehicle trips), and estimated vehicle delay at select study intersections. • Results from community survey on top priorities for travel on El Camino Real.
In response to these existing conditions, the Project team considered these options for the study corridor:
• For walk facilities, all build alternatives included adding new sidewalks on both sides of the street where they do not currently exist.
• For bike facilities, the build alternatives considered four types of solutions • No dedicated bikeways.
• On-street bike lanes (Class II bikeways) on each side of the street. • One-way buffered bike lanes (Class II bikeways) or separated bikeways (Class IV bikeways), either roadway or elevated grade.
• Two-way separated bikeways (Class IV bikeways) on one side of the street, typically the west side of El Camino Real.
• For transit facilities, the build alternatives considered • Shared lanes with vehicles.
• Bus only lanes.
• Bus stop improvements.
1 2014 Town of Atherton Bike and Pedestrian Master Plan, Menlo Park El Camino Real Corridor Study, San Mateo County C/CAG Comprehensive Bicycle and Pedestrian Plan, Countywide Transportation Plan, Reimagine SamTrans initiative, Grand Boulevard Initiative, MTC Active Transportation Network, Caltrans SHOPP Project #1W130, Caltrans District 4 Bike Plan.
WSP 474-1585-069
Design Concepts Summary Memo March 18, 2025
Parametrix Technical Memorandum
• For drive facilities, the build alternatives considered Retaining the existing vehicular travel lanes, predominantly three vehicle lanes in each direction with two northbound through lanes in Menlo Park.
Providing two through vehicle lanes in each direction along the full length of the study area.
• Providing three vehicle lanes in one direction and two vehicle lanes in the other direction, for either the full extent or alternating sides. • Retaining or removing on-street parking depending on the vehicle lane and bikeway configuration.
The Project team developed seven initial alternatives that applied the facility options presented above to the existing El Camino Real right of way; they are described below and summarized in Table
1. Table 1 - Preliminary Concepts
# Prellminary Concept Walk Facllity Bike Facllity Transit Fallity Drive Facllity No Build None None Shared w\ vehicles 3 lanes (where
(3 lanes) currently present)
Signed bus stops
Sidewalk & Landscape Only Sidewalk both sides one/shared lage Shand vehicles ures prese currently present)
ereen paint (optiona Widened bus stops
Sidewalk & Sidewalk both sides Bossie bike lane Shaned w vehicles 3 lanes (where On-Street Bike Lane both sides currently present)
Narrow bus stops
3 Sidewalk, Landscape & Sidewalk both sides None Bus only lane 2 lanes with right Bus-Only Lane turn lanes at
Widened bus stops intersections
Two one-way
4 Sidewalk, Landscape & Sidewalk both sides M Seten eways Shand w vehicles 2 anes nevered Bike Lad Bikeways W\ sections of
Buth sid bike lanes Widened bus stops
One-way Separated Bikeways Medium sidewalk Two one-way Shared w\ vehicles 2 lane:
(Sidewalk Grade) both sides separated bikeways (2 lanes Widened bus stops
Two-way Separated Bikeway & Medium sidewalk One two-way Shared w\ vehicles 2 lanes Bike Lane one side, wide separated bikeway (2 lanes)
sidewalk on other
side Widened bus stops
Asymmetrical Vehicle Lanes & Sidewalk both sides One two-way Shared wl vehicles 3 lanes in one Two-way separated bikeway separated bikeway (2/3 lanes) direction & 2 lanes in the other direction
Widened bus stops
WSP 474-1585-069
Design Concepts Summary Memo 3 March 18, 2025
Parametrix Technical Memorandum
The Project team developed an evaluation matrix and scoring system to screen and score the seven initial alternatives. The screening methodology used four overarching goals:
• Quality of life - Retention of on-street parking, provision of an attractive environment for active transportation, protection of adjacent neighborhoods from traffic diversion, and change in vehicle travel time and speeds.
• Safety - Reduction in conflicts and increase in modal separation, improvement to roadway crossing and roadside visibility, and potential to improve flooding (stormwater) conditions. • Multimodal Equity and Access - Gap closures in walk, bike, and transit networks; creation of multimodal travel opportunities; and improvement in access for disadvantaged communities and community at large.
• Construction - Cost and complexity
The Project team either screened out or selected the preliminary alternatives to advance into the conceptual design stage for the reasons listed below. The evaluation of the seven preliminary alternatives is shown in Table 2.
• Preliminary Alternative 1, sidewalk and landscape only and three vehicle lanes: This alternative scored high in maintaining drive capacity and scored low in safety and multimodal access. Alternative 1 scored worse than Alternative 2, another alternative that maintains three drive lanes on El Camino Real and was therefore not advanced into the next project phase.
Preliminary Alternative 2, narrow sidewalks, on-street bike lanes and three vehicle lanes:
This alternative closes the bikeway and sidewalk gaps at a minimum comfort and safety standard while retaining the existing lane configuration of El Camino Real. This alternative scored high in maintaining drive capacity and scored low or medium for safety and multimodal access. Alternative 2 was advanced into the next project phase as the better- scoring concept that retains three drive lanes on El Camino Real as Concept #1 Added Sidewalks and Striped Bike Lanes (Appendix A).
Preliminary Alternative 3, sidewalk, landscape, two vehicle lanes, and bus-only lane: This alternative scored medium in maintaining drive capacity, scored low or medium in safety, and scored low or medium in multimodal access. Alternative 3 scored comparably to the alternatives with bikeways (Alternatives 4 through 7); its lack of bike lanes is inconsistent with the planning documents for El Camino Real and was therefore not advanced into the next project phase.
Preliminary Alternative 4, wide sidewalks, buffered bike lanes, and two vehicle lanes: This alternative closes the bikeway and sidewalk gaps at a preferred comfort and safety standard, with the key tradeoff being the reduction to two through vehicle lanes in each direction. This alternative scored low or medium in maintaining drive capacity, scored medium or high in safety, and scored high in multimodal access. This alternative was renamed Concept #2 Wider Sidewalks & Buffered/Protected Bike Lanes in the next project phase (Appendix A).
Concept 2 includes the possibility of separated bikeways and elevated (sidewalk grade) separated bikeways that were considered as part of Preliminary Alternative 5 and 6.
Preliminary Alternative 5, wide sidewalks, separated bike lanes (roadway of sidewalk grade), and two vehicle lanes. This alternative scored low or medium in maintaining drive capacity, WSP 474-1585-069
Design Concepts Summary Memo 4 March 18, 2025
Parametrix Technical Memorandum
scored medium or high in safety, and scored high in multimodal access. This alternative has the same effective number of vehicle lanes on El Camino Real (two in each direction) as Alternative 4 and was therefore incorporated into Concept #2 as a design variant, as noted above.
Preliminary Alternative 6, wide sidewalks, two-way separated bike lanes, and two vehicle lanes. This alternative scored low or medium in maintaining drive capacity, scored medium or high in safety, and scored high in multimodal access. Alternative 6 scored comparably to the alternatives with one-way bikeways (Alternatives 4 and 5); its two-way bikeway on one side of the road is inconsistent with the plans for El Camino Real by other jurisdictions and was therefore not advanced into the next project phase.
Preliminary Alternative 7, medium sidewalks, two-way separated bikeway on one side, and alternating two or three vehicle lanes: This alternative scored low or medium in maintaining drive capacity, scored medium in safety, and scored medium or high in multimodal access.
This alternative closes the bikeway and sidewalk gaps while alternating the potential sections of vehicle lane reduction and parking reduction on El Camino Real. Alternative 7 was advanced into the next project phase and renamed Concept #3 Wider Sidewalks and Partial Buffered/Protected Bike Lanes in the next project phase; Concept 3 further modified to provide one-way separated bikeways instead of a two-way bikeway, as shown in the conceptual design work described in the next section (Appendix A).
Table 2 Prellminary Concepts Screening
3 2 sW + 4 5 3Ỉn/2
6 1 SW+ Bus 1-way Sep 1-way Sep 2-way
No S/W+ Bike Only / Buffer Bike Sep Bike 2-way Sep
Goal Objective Bulld LS Lane Lane Bike Lane. (Ralsed) (Ralsed) Bike Quality of Addresses stakeholder None High High High Medium Medium Medium High Life concerns (on-street parking
and frontage access)
tractive environment f None Low Low Low High High High High tive transportatic
Maintains automobile travel None High High Medium Medium Medium Medium Medium time and speeds on ECR
Safety Reduces conflicts/modal None Low Low Low High High High High separation
Improves crossing None Low Low Low Medium High High Medium movements and roadside
visibility (e.g., lighting)
Addresses flooding impacts None Medium Low Medium Medium Medium Medium | Medium Multimodal Fills gap in biking, walking, None Low Medium Medium High High High High Options, and transit network
Equity &
Access
Creates more opportunities | None Low Low Low High High High High for multimodal travel
WSP 474-1585-069
Design Concepts Summary Memo 5 March 18, 2025
ParametriX Technical Memorandum
Improves access for None Low Low Medium High High High High disadvantaged
communities
Construction Cost & complexity None Medium Low Medium Medium High High High
2. Conceptual design of screened alternatives and evaluation The following section summarizes the refined conceptual designs and their performance against the project evaluation criteria (see Section 2.2 below).
2.1 Conceptual Design Description
The project team's surveyor, Unico, collected a topographic survey of the full project extents, inclusive of the existing curb lines, edge of pavement, trees with trunk size, lane and parking markings, above-ground utilities, and elevations. Parametrix used the topographic survey as a base map to develop concept designs for the three concepts across three typical sections of El Camino Real. The drawing extents total to approximately one-third of the 1.5-mile study extents and are included in the appendix (Appendix B).
• Segment 1, from Selby Lane to Fifth Avenue
• Segment 2, showcasing the Atherton Avenue/Fair Oaks Lane intersection • Segment 3, from Encinal Avenue to Valparaiso Avenue/Glenwood Avenue.
During the conceptual design stage, the Project team identified design elements that apply to all concepts
• Two alternatives for traffic control at Selby Lane: a new traffic signal or installation of a High Intensity Activated Crosswalk (HAWK) beacon with elimination of through left-turn movements for vehicles at each approach to El Camino Real. • New proposed raised median features to shield people walking in crosswalks ("refuges"). • Multiple proposals for bikeway infrastructure and pavement markings to facilitate bicycle movements along and across El Camino Real.
• Proposals for some bus stops to relocate to the far side of the intersection with required accessibility improvements.
• Proposals for new crosswalks with new corner curb ramps and island refuge areas. • Retention of the existing turn pockets and as many raised medians as possible along El Camino Real.
• New traffic signal at Watkins Avenue (mitigation for Caltrain Electrification Project). • New HAWK beacons at Tuscaloosa Avenue and Stockbridge Avenue to facilitate pedestrian mobility.
• Curb and gutter improvements with drain inlets along the project length to manage stormwater runoff.
WSP 474-1585-069
Design Concepts Summary Memo 6 March 18, 2025
Parametrix Technical Memorandum
• New lighting and signage improvements in Atherton to promote safety for active transportation.
The refined Concept #1 (Added Sidewalks and Striped Bike Lanes) proposes to retain the existing vehicular travel lanes in each direction of El Camino Real (Appendix B, Sheets P-1 and 2). • Northern end, in North Fair Oaks from north of Selby Lane to Wilburn Avenue, the proposal is a northbound Class II bike lane to the right of the number 3 lane, removal of existing curbside parking, and no change to the existing sidewalk, curb and gutter.2 • In the southbound direction from north of Selby Lane to Menlo College Drive/Encinal Avenue and in the northbound direction in Atherton between Watkins Avenue to Wilburn Avenue, the proposal is on-street bike lanes (Class II bikeways) to the right of the number 3 lane, narrow uniform sidewalks, and new curb and gutter.
• Southern end, in Menlo Park from Watkins Avenue to Glenwood Avenue/Valparaiso Avenue, the proposal is a northbound Class Il bike lane between the number 2 lane and on-street parking; no change to the existing sidewalk, curb and gutter; and retention of the existing vehicle through and right turn lanes, addition of sidewalk, and transition of the bike lane as it approaches Valparaiso Avenue.
The refined Concept #2 (Wider Sidewalks & Buffered/Protected Bike Lanes) proposes to reduce El Camino Real to two vehicle lanes in each direction (Appendix B, Sheets P-3 and 4). • In the southbound direction from north of Selby Lane to Encinal Avenue and in the northbound direction from Watkins Avenue to Wilburn Avenue, the proposal is buffered bike lanes (Class Il bikeways) or separated bikeways (Class IV bikeways) to the right of the number 2 lane, wide sidewalks, and removal of the third vehicle lane. • In the southbound direction from Encinal Avenue to Valparaiso Avenue, the proposal is buffered bike lanes (Class II bikeways) or separated bikeways (Class IV bikeways) to the right of the number 3 lane/right turn pocket at Valparaiso Avenue. • In the northbound direction in Menlo Park, from Glenwood Avenue/Valparaiso Avenue to Watkins Avenue, the proposal is buffered bike lanes (Class Il bikeways) or separated bikeways (Class IV bikeways) to the right of the number 2 lane, removal of existing curbside parking, and no change to the existing sidewalk, curb and gutter. • In the northbound direction in North Fair Oaks, from Wilburn Avenue to Selby Lane, the proposal is buffered bike lanes (Class II bikeways) between the number 2 lane and on-street parking, removal of the third vehicle lane, and no change to the existing sidewalk, curb and gutter.
• Separated bikeways at an elevated (sidewalk) grade are noted as potential design options for Concept 2 rather than as a separate concept due to its minor effect on the facility layout and roadway operations.
The refined Concept #3 (Wider Sidewalks and Partial Buffered/Protected Bike Lanes) proposes to alternate two and three vehicle lanes on El Camino Real in each direction with painted bike lanes 2 Lane numbering follows the Caltrans Highway Design Manual (Section 62.1(1)) convention, where "On a multilane roadway, the lanes available for through travel in the same direction are numbered from left to right when facing in the direction of travel."
WSP 474-1585-069
Design Concepts Summary Memo 7 March 18, 2025
Parametrix Technical Memorandum
next to the three-lane sections and separated bikeways next to the two-lane sections (Appendix B, Sheets P-5 and 6).
• Concept #3 changed considerably from the preliminary alternatives development stage, which proposed a two-way bikeway. This proposal had significant tradeoffs, including incompatibility with the one-way bikeways proposed on El Camino Real in adjacent jurisdictions, greater complexity in intersection traffic control, and requiring bicyclists passing through Atherton to cross the street.
• Concept #3 was amended to retain the asymmetrical vehicle lane arrangement on El Camino Real with one-way bikeways on each side of the street. The transition from two to three vehicle lanes on southbound El Camino Real was placed at Fair Oaks Lane. The transition from two to three vehicles lanes on northbound El Camino Real was placed at Atherton Avenue. This was intended to maximize roadway lanes where traffic conditions warranted more capacity.
2.2 Conceptual Design Evaluation
The Project team developed six metrics to evaluate the Conceptual Designs:
• Bicyclist safety, based on the type of proposed bikeway and degree of separation from vehicular traffic.
• Pedestrian safety, based on the proposed sidewalk width, potential conflicts with existing utilities and above-ground features, and degree of separation from vehicular traffic. • Ability to address flood (stormwater) issues, based on the opportunity to add landscaping and stormwater catchment and conveyance features.
• Ability to maintain existing vehicle travel speeds, based on vehicle demand and roadway capacity.
• Ability to minimize traffic diversion to and queuing on local streets, based on vehicle demand and roadway capacity.
• Ability to maintain on-street parking.
The three conceptual design drawings (Appendix B) were used to evaluate the proposals against the six metrics listed above. The traffic operations of the Concepts were analyzed and documented by WSP.3 The scores for each Concept are presented in Table 3. Among the findings:
For bicyclist and pedestrian safety, Concept #1 scored Low, Concept #3 scored Medium, and Concept #2 scored High, consistent with the proposed sidewalk widths, bikeway widths, whether there is the possibility of a horizontal and vertical buffer, and separation with vehicle traffic.
• All concepts scored Medium for flood impacts, as all concepts would include new curb and gutter and stormwater infrastructure in Atherton. However, there is a marginal difference in potential landscaping between concepts and its effect on stormwater runoff and management.
3 WSP (2025) Task 3.2.2 Memo Supplemental, - Travel Demand Forecasts WSP 474-1585-069
Design Concepts Summary Memo March 18, 2025
Parametrix Technical Memorandum
• For minimizing traffic diversion onto local streets, WSP developed a travel demand model to estimate the change in approach and departure volumes at each of the 12 project intersections.
• The No Project and Concept 1 volumes are the same, as the roadway configurations for those alternatives are the same.
• Concept 2 traffic volumes along El Camino Real reduce the most relative to the No Project/ Concept 1.
• Concept 3, traffic volumes are not reduced as significantly relative to the No Project/ Concept 1 baselines, but they still are less along El Camino Real.
Since El Camino Real is a major regional facility that carries both local and through traffic, the reduction in capacity would cause through vehicle trips to divert to parallel arterials and freeways if the travel time increase is significant enough on El Camino Real. As such, Concept #1 scored High, Concept #3 scored Medium-High, and Concept #2 scored Medium.
It should be noted that the Oakwood Drive/Oakwood Blvd and Atherton Avenue/Isabella Avenue/Alejandra Avenue locations have significant traffic calming infrastructure in place (speed bumps/speed tables), which the demand model would not consider in the route diversions, which implies that the demand model may be overestimating the impact of the local street traffic diversion and the traffic may actually stay on El Camino Real. Nonetheless, the results of the diversion analysis identifies areas that might need to be monitored to minimize diversion.
For maintaining vehicle speed, WSP developed a corridor model to forecast changes in travel time and average speed at commute peak hours based on forecast traffic volumes, changes in roadway configuration, and proposed signals and beacons. • Concept 1 forecast average travel speeds were commensurate with existing conditions, approximately 20 mph inclusive of stop delays at controlled intersections.
Concept 2 was forecast to decrease travel speeds in the peak direction by 30-40 percent (6-8 mph slower) and Concept 3 was forecast to decrease travel speeds by 5-30 percent (1-6 mph slower).
Concept 1 forecast travel times were commensurate with existing conditions.
Concept 2 was forecast to increase travel time in the peak direction by 30-50 percent (2-3 minutes longer) and Concept 3 was forecast to increase travel time by at most 30 percent (2 minutes longer).
As such, Concept #1 scored High, Concept #3 scored Medium-High, and Concept #2 scored Medium, consistent with the projected impacts on travel speeds and congestion level of service (LOS).
As for minimizing loss of on-street parking on El Camino Real, each concept had differing impacts. Currently, there is allowed parking only in the northbound direction within the North Fair Oaks neighborhood (Selby Lane to Wilburn Avenue, approximately 35 parking spaces) and in Menlo Park (Watkins Avenue to Glenwood Avenue/Valparaiso Avenue, approximately 35 spaces). There is no parking allowed in the Town of Atherton portion of El Camino Real. • Generally, Concept 1 requires less space to fit the bike lane and is therefore scored "Medium". However, in North Fair Oaks specifically, there is no wide shoulder so the parking lane must be replaced to accommodate the bike lane. As such, Concept #1 WSP 474-1585-069
Design Concepts Summary Memo March 18, 2025
ParametriX Technical Memorandum
is estimated to remove the on-street parking in the North Fair Oaks neighborhood (~35 spaces), while retaining on-street parking in Menlo Park.
Generally, Concept 2 requires more space to fit the wider and buffered bike lane and is therefore scored "Low." However, in North Fair Oaks the outside travel lane (instead of the parking lane) is replaced with the bike lane. As such, Concept #2 is estimated to retain on-street parking in the North Fair Oaks neighborhood while removing on-street parking in Menlo Park (~35 spaces).
Concept #3 is estimated to remove on-street parking in both the North Fair Oaks neighborhood (~35 spaces) and Menlo Park (~35 spaces). As such, concept #3 scored Low.
Table 3 Conceptual Design Evaluation Scores
Metric Concept #1 Concept #2 Concept #3
Bicyclist Safety Low High Medium
Medium in North Fair Oaks
Pedestrian Safety Low High Medium
Addresses Flood Impacts Medium Medium Medium
Retains Travel Speed High Medium Medium-High
Minimizes Traffic Diversion to High Medium Medium-High
Local Streets
Maintains Street Parking Medium Medium Low
Low in North Fair Oaks ligh in North Fair Oaks Low in North Fair Oaks High in Menlo Park _ow in Menlo Par Low in Menlo Park
2.3 Planning-Level Cost Estimate
This section presents the methodology for generating a project feasibility cost estimate in accordance with the Caltrans Project Development Procedures Manual (PDPM).4 The primary approach for generating the cost estimate is canvassing the cost data of comparable projects and generating a cost per linear foot of road basis. There are three comparable projects near the Project area of similar size and scope, summarized in Table 4 and described below.
Comparable Projects
The El Camino Real Roadway Renewal Project spans 3.6 miles in San Mateo County along El Camino Real/State Route 82. Caltrans is the implementing agency for the project, whose scope "proposes to rehabilitate the roadway and sidewalks, improve safety and visibility, remedy drainage issues, and upgrade curb ramps." The project includes removing 300-350 trees; the scope does not include utility undergrounding. The estimated cost according to City of Burlingame City Council Update (Oct 2024) is between $130 and $140 million (2024), or approximately $40 million per mile. 4 https://dot.ca.gov/-/media/dot-media/programs/design/documents/pdpm-chapter20-a11y-old.pdf WSP 474-1585-069
Design Concepts Summary Memo 10 March 18, 2025
Parametrix Technical Memorandum
The Middlefield Road Improvement Project in the North Fair Oaks neighborhood of unincorporated San Mateo County spans 0.4 miles between Pacific Street and 5th Street. San Mateo County is the implementing agency. The project converts the four-lane roadway to three lanes with bike lanes in a commercial corridor; it includes utility undergrounding, upgraded streets, sidewalks, curb ramps, landscaping, and street furnishings. The estimated cost is between $21 and $25 million (2022), or approximately $50-60 million per mile. Escalated to 2025, the per mile cost is between $60 and $70 million.
The Middlefield Road Streetscape Project in the City of Redwood City spans 0.4 miles from Maple Street to Woodside Road and was completed in 2024. The project scope included utility undergrounding; upgraded streets, sidewalks, curb ramps, protected bike lanes and landscaping; the construction cost was approximately $8 million (2018), which is equivalent to approximately $20 million per mile. Escalated to 2025, the per mile cost is approximately $30 million.
The El Camino Real Roadway Renewal Project is the most analogous to the proposed project in its jurisdiction and project scope.
Construction Cost Estimate, Escalation, and Contingencies Using the El Camino Real Roadway Renewal Project's estimated cost of $40 million per mile and applying it to the Project extents (1.5 miles) yields a ROM cost of $60 million (2025 dollars).
Consistent between the two El Camino Real projects, the major cost items are expected to be roadway rehabilitation, new sidewalks, new curb and gutter, safety improvements (e.g., traffic control devices), stormwater infrastructure, and new curb ramps. With the additional potential cost of $5 million for stormwater infrastructure, the estimated project cost is elevated to be $60-65 million. The cost difference between the three Concepts for the bikeway options and varying sidewalk widths is expected to be minor. Consistent with State guidelines, the initial probable continency as a percentage of construction cost is estimated at 10-15%. The resulting construction cost range with contingency is $70-80 million.
Potential high-cost items that could increase the project cost include:
• Mitigating hazardous waste.
• Mitigating environmental impacts associated with existing mature trees and natural waterways.
• Utility relocation to mitigate conflicts with above-ground utility poles. • Noise barriers and retaining walls.
• Major stormwater infrastructure (e.g., pump stations, water mains) in Atherton.
Transportation management plan and traffic handling during construction.
WSP 474-1585-069
Design Concepts Summary Memo 11 March 18, 2025
Parametrix Technical Memorandum
Table 4 Comparable Project Summary
Jurisdiction Caltrans
Project Name El Camino Real Roadway Renewal Project
Project Extents and Length El Camino Real/State Route 82 in San Mateo County Post mile (PM) 12.3, East Santa Inez Avenue, in the City of San Mateo, to PM 15.9,
3.6 miles
Project Scope Varies: Up to 130-foott right of way (4-6-lane arterial highway) ehabilitate the roadway and sidewalks, improve safety and visibility, remedy drainag sues, and upgrade curb ramps. Remove 300-350 tree
Project Cost (Construction) $137.2M (2024)
Project Cost per Mile $38.1M (2024)
Reference https://dot.ca.gov/-/media/dot-media/district-4/documents/d4-environmental- docs/82-el-camino-real-roadway-renewal-project/sm-82-final-eir-eis-508-pf3-a11y.pdf Jurisdiction County of San Mateo
Project Name Middlefield Road Improvement Project
Project Extents and Length Middlefield Road, from Pacific Street to 5th Street,
0.4 miles
Project Scope 86-foott right of way
Conversion from 4-lane to 3-lane roadway. Utility undergrounding; upgraded streets, sidewalks, curb ramps, landscaping, and street furnishings.
Project Cost (Construction) $21-25M (2022)
Project Cost per Mile $50-60M (2022)
Reference https://www.smcgov.org/publicworks/middlefield-road-project-description Jurisdiction City of Redwood City
Project Name Middlefield Road Streetscape Project
Project Extents and Length Middlefield Road, from Maple Street to Woodside Road
0.4 miles
Project Scope 76-foott right of way (3-lane roadway)
Utility undergrounding; upgraded streets, sidewalks, curb ramps, protected bike lanes and landscaping.
Project Cost (Construction) $8M (2018)
Project Cost per Mile $20M (2018)
Reference https://www.redwoodcity.org/city-hall/current-projects/infrastructure-projects?id=127 WSP 474-1585-069
Design Concepts Summary Memo 12 March 18, 2025
Parametrix Technical Memorandum
3. Next Steps: Selection of a preferred design
The planned outcome at the conclusion of the Study is the selection of one or more preferred Concepts that will advance into the Caltrans Project Initiation Document (PID) stage, during which the project scope will be further developed, technical studies undertaken, and the cost estimate developed with greater detail.
WSP 474-1585-069
Design Concepts Summary Memo 13 March 18. 2025
Parametrix Technical Memorandum
Appendix
Appendix A: Conceptual Cross Sections
Appendix B: Conceptual Design Plan Drawings
WSP 474-1585-069
Design Concepts Summary Memo 14 March 18. 2025