Technical Memorandum

DATE:   August 17, 2023

TO:         Meghan Jop, Town of Wellesley

FROM:   Casey Cooper, Boston Region MPO

RE:         Wellesley Intersection Improvement Study

This memorandum summarizes the analyses and improvement strategies for the intersection of Linden Street and Weston Road in Wellesley.

This memorandum contains the following sections:

• Study Background
• Existing Conditions
• Issues and Concerns
• Bicycle and Pedestrian Travel
• Crash Data Analysis
• Intersection Analysis
• Improvement Recommendations
• Conclusions and Next Steps

The memorandum also includes technical appendices that contain data and methods applied in the study.

Study Background

The purpose of this study is to improve safety and operations at intersections within the Boston Metropolitan Planning Organization (MPO) region with a focus on cost- and time-effective strategies. The intent of the work is to identify simple solutions that can be used to enhance intersection conditions in the short term. These changes have the potential to serve as a first step before municipalities secure funding for larger scale projects to improve conditions at the intersection in the future.

In 2014, the Boston Region MPO participated in an intersection improvement program with the Massachusetts Department of Transportation (MassDOT) Highway Division to provide low-cost, small scale, and quickly implementable improvements, including signal retiming, signing, and pavement markings. The program was funded in the Transportation Improvement Program with Congestion Mitigation and Air Quality dollars.

The primary goal of the program was to identify low-cost improvements that would help alleviate congestion at problem intersections. These types of small-scale improvements enjoy a high benefit-to-cost ratio. Through the 2014 iteration of the Intersection Improvement Program, MPO staff selected candidate intersections and contacted the relevant municipalities using the Congestion Management Process. Howard Stein Hudson, a consulting firm, visited 35 intersections around the region, implemented signal timing improvements, and proposed other low-cost improvement recommendations that municipalities could implement.

The Intersection Improvement Program was reintroduced through the federal fiscal year 2021 Unified Planning Work Program with modifications to the original work. This project is on a smaller scale than the 2014 effort, carried out solely by MPO staff, and focused on providing recommendations that municipalities can implement themselves to improve the selected intersections.

This work gives the communities in which the intersections are located the opportunity to look at the needs of the studied intersections, with a focus on changes that the municipalities themselves can implement quickly and within their current operating budgets to improve safety and operations. This project also highlights significant intersection needs before the municipality commits funds for design and engineering. Eventually, if the project qualifies for federal funds, this study’s documentation is useful to MassDOT. This study supports the MPO’s visions and goals, which include increasing transportation safety, maintaining the transportation system, and advancing mobility.

This iteration of the Intersection Improvement Program began with the selection of municipality-owned intersections. MPO staff solicited recommendations from the community and compared the proposed locations based on crash averages, equity data, and consideration of which intersections’ needs would be best addressed through this project. MPO staff consulted with municipal staff to validate the poor operations and safety issues at each intersection under consideration before finalizing the location selections. The following locations were selected for study:

• Route 117 and Route 62 in Stow
• Linden Street and Weston Road in Wellesley

This memorandum documents MPO staff’s analysis of the selected intersection of Linden Street and Weston Road in Wellesley. The recommendations for low-cost improvements outlined in this document can be used by Wellesley to develop a safety and traffic operation implementation plan for the location that the municipality would be responsible for funding.

Existing Conditions

Regional Transportation Context

Wellesley is a town located west of Boston with a 2020 population of 29,550. It has a land area of 10.5 square miles, giving it an average population density of 2,814 persons per square mile. The Metropolitan Area Planning Council characterizes Wellesley as a maturing suburb.

Wellesley is located just southwest of the interchange of Interstate 90 (I-90) and I-95. I-90 is a critical east-west limited-access corridor, but direct access to businesses and residences west of Boston is provided by several east-west arterial roadways, such as Route 9 and the parallel Route 135 to its south.

Route 135 and Route 16 function together as a single, extended east-west corridor from Newton to Framingham. Route 16 traffic joins with Route 135 in Wellesley Square and then continues west to Natick and Framingham on Route 135. This section of Route 135 in Wellesley is called Central Street.

Just west of Wellesley Square, there is a signalized intersection where Route 135 meets Weston Road. Weston is a north-south arterial that connects the Wellesley and Weston town centers. It also connects with the partially limited-access Route 9 at a Depression-era mini-cloverleaf. The intersection of Weston Road and Route 135 is about 13 miles west of downtown Boston (Figure 1).

Figure 1
Wellesley within the Boston MPO Region

In the communities of Wellesley, Natick, Framingham, and Ashland, Route 135 is near or immediately adjacent to the Worcester commuter rail line on its south side. Almost all the roadways crossing the rail line are grade separated, including Weston Road, which includes a bridge to move traffic over the line.

Only 300 feet north of the Route 135 intersection, Weston Road has another signalized intersection with Linden Street, the primary intersection considered in this study (Figure 2). Linden Street parallels the rail corridor on its north side through most of Wellesley’s downtown area. Due to the proximity of these two intersections, recommendations proposed for the Linden Street intersection have the potential to affect traffic operations at the Route 135 intersection. Figure 3 documents how traffic from Weston Road’s intersection with Central Street can stretch to the study area at Linden Street and Weston Road. For the purposes of this study, therefore, traffic operations at both intersections will be considered. Figure 4 illustrates the proximity of these two intersections and their location within Wellesley.

Figure 2
Intersection Study Area: Linden Street and Weston Road

Figure 3
Study Location View Looking South along Weston Road toward Central Street

Figure 4
Study Area Proximity to Intersection of Central Street (Route 136)
and Weston Road

The Study Intersection

The intersection of Linden Street and Weston Road is within walking distance of several destinations. The eastern terminus of the Crosstown Trail is less than 200 feet from the study location. The Crosstown Trail travels through North 40, a 46-acre undeveloped parcel of land owned by Wellesley that features walking trails, a vernal pool, and the Weston Road Community Gardens.1 The Wellesley Square Commercial District and Wellesley College both begin at the intersection of Weston Road and Central Street about 300 feet south of the study location. Finally, Wellesley Square Station, which serves the Framingham/Worcester commuter rail line, is located 0.3 miles east of the study intersection.

The intersection of Linden Street and Weston Road is a T intersection, with the western terminus of Linden Street meeting Weston Road (Figures 5 and 6). The intersection is signalized but operates with flashing yellow lights for Weston Road and a flashing red light for Linden Street until pedestrian actuation calls for a pedestrian crossing phase. The pedestrian phase stops all vehicular traffic and allows for an exclusive pedestrian crossing phase of both Linden Street and Weston Road across the north leg of the intersection. Signage informs motorists at Weston Road’s northbound approach that there is “No Turn on Red.” The same signage marks the Linden Street approach, accompanied by an “Except When Flashing” sign because the Linden Street signal flashes red by default (Figure 7).

Figure 5
View of Weston Road from the South Side of Linden Street at the T Intersection

Figure 6
View of Linden Street T Intersection, Looking North along Weston Road

Figure 7
No Turn on Red Signage at Study Intersection

Both Weston Road approaches include one lane that accommodates both through and turning traffic. The Linden Street approach features two lanes, one for right turns and the other for left turns. All three legs of the intersection are striped with one departure lane.

The Town of Wellesley zoning map shows that the entire intersection area is zoned “General Residence.” The west side of Weston Road at the intersection is also a “Residential Incentive Overlay District.” The lot directly west of the intersection at 112 Weston Road is a multifamily home, with vegetation to the north and Weston Road’s bridge over the Worcester commuter rail tracks to the south. The north corner of the intersection, north of Linden Street and east of Weston Road, features multifamily housing in The Wellesley Townhouses. South of Linden Street and east of Weston Road on the southeastern corner of the intersection is another multifamily housing development (Figure 8).

Figure 8
Southeast Corner of Study Intersection

Issues and Concerns

The intersection of Linden Street and Weston Road is heavily used by people walking and bicycling to many destinations. In addition to the nearby attractions listed above, the location is within one mile of the town’s Sprague Elementary, Hardy Elementary, and Wellesley Middle schools.

One of the biggest concerns at the intersection occurs when pedestrian activation stops all vehicular traffic. Motorists will turn despite the red light or impede the crosswalk while stopped at the light when traffic is backed up along Weston Road, creating dangerous conditions for people using the intersection’s crosswalks.

Wellesley has approved a 26-unit residential development north of the Linden Street and Weston Road intersection. In addition, the multifamily development on the southeast corner of the intersection will be growing with additional residences. The increasing number of people living near the study location means that more people will be traveling through the intersection. Ensuring safe travel through the location is imperative, but by making the location as comfortable for bicycle and pedestrian travel as possible, the Town of Wellesley could also reduce vehicle demand at the intersection by encouraging residents to walk or bike to their destinations instead.

The intersection of Linden Street and Weston Road is on Wellesley’s Complete Streets prioritization list, meaning that the Town wants to make the location safe and accessible for everyone of all ages and abilities: people walking; people bicycling; people using mobility devices: people using transit; and people in personal, commercial, and emergency vehicles. To improve conditions for all road users, Wellesley will be updating Weston Road’s Linden Street and Central Street intersections with adaptive controls in the future. This will allow signal timings at both intersections to adapt to current conditions, optimizing the flow of traffic.

The most significant impact to traffic flow through the intersection is made by people on Linden Street making southbound turns on Weston Road, toward the Central Street intersection. This movement causes the largest traffic backups at the location.

The proximity of the Linden Street intersection to Central Street’s intersection with Weston Road approximately 300 feet south is an important characteristic of the location, especially when considering the limited sightlines introduced by the Weston Road bridge over the Worcester commuter rail tracks. The inability to observe traffic conditions on the side of the roadway over the bridge reinforces the need to travel safely along Weston Road between the two intersections.

On July 7, 2023, the study intersection was included in a Road Safety Audit (RSA) conducted in Wellesley. The RSA considered Weston Road from Linden Street to Central Street (Route 135) and Central Street (Route 135) from Weston Road to Cross Street. Additional documentation of current conditions and safety concerns can be found in the RSA (Appendix H).

Finally, in 2012, a bicyclist was hit and killed traveling north on Weston Road at the study intersection. Wellesley wants to prevent any such tragedy from recurring in the future.

Bicycle and Pedestrian Travel

Bicycle and Pedestrian Overview

On November 18, 2021, the AM Peak hour at the Linden Street and Weston Road intersection was 8:00 AM to 9:00 AM and the PM Peak hour was 3:00 PM to 4:00 PM. The overall peak hour of data collection for all modes occurred during this PM Peak period. During the AM Peak, 17 pedestrians were counted, while 26 were counted during the PM Peak. The AM Peak featured four bicyclists in the road and two on the sidewalk, while the PM Peak didn’t include any bicyclists in the road and three people bicycling on the sidewalk.

Bicycle facilities are not present at the intersection to facilitate bicycle travel.

Linden Street’s connection to Weston Road features pedestrian actuated signals with countdown displays for two of the three intersection legs. Painted crosswalks accompany both crossings. Three curb ramps assist travel into the roadway, accompanied by detectable warning strips that alert users to the transition from sidewalk to roadway. On the northern corner of the intersection, a curb ramp and detectable warning strip pair serves each of the two crosswalks (Figure 9).

Figure 9
View of North Corner Curb Ramp and Detectable Warning Strip Pairs

The curb ramps and detectable warning strips are surrounded by concrete sidewalk, but only the sidewalk traveling south on the east side of Weston Road maintains the concrete material. Both sides of Weston Road north and Linden Street east of the intersection quickly transition from concrete to asphalt sidewalks. The west side of Weston Road south of the intersection does not feature sidewalks at all.

Figure 10
Sidewalk on East Side of Weston Road Looking North to Study Intersection

MPO staff graded the intersection of Linden Street and Weston Road in Wellesley using the Boston Region MPO’s Pedestrian Report Card Assessment (PRCA)2 and Bicycle Report Card3 tools to assess the safety and comfort of the location for people walking and bicycling. The grading categories reflect the MPO’s Long-Range Transportation Plan (LRTP) goals and assess the quality of four different aspects of the environment: Capacity Management and Mobility, Economic Vitality, Safety, and System Preservation. The report cards also prioritize locations based on Transportation Equity factors, incorporating another Boston region LRTP goal.

Pedestrian Report Card Assessment (PRCA)

Figure 11
Signalized Intersection PRCA for Linden Street and Weston Road

The intersection received a “Good” score for Capacity Management and Mobility on its PRCA, which was largely influenced by the minimal delay experienced by pedestrians trying to cross the intersection. Within seconds of actuating the pedestrian signal button, vehicle traffic receives a solid yellow signal, followed by a solid red light, after which the pedestrian crossing phase begins. The location lacks a sidewalk on the west side of Weston Road south of the intersection, there is not a curb ramp on the southwest corner, and the southern leg of the intersection does not feature a crosswalk, but people walking do not have to wait long for vehicular traffic to stop when they actuate the pedestrian signals at Linden Street and Weston Road. This, coupled with the decent sidewalk, curb ramp, and crosswalk conditions throughout the remainder of the intersection, earned the location a high score in the first grading category.

For Economic Vitality, the intersection received a “Fair” score, given that between five and 60 people an hour were observed walking through the location.

The intersection was deemed fair for all four performance metrics in the Safety category, earning the intersection a “Fair” score. Best practice recommends providing sufficient time for people walking to cross an intersection leg at a pace of 3.5 feet per second if they have left the curb at the end of the WALK phase.4 In areas known to have pedestrians who walk more slowly or areas with considerable numbers of people using mobility devices, slower speeds should be considered. Given the width of the Linden Street crossing, the combined Flashing Don’t Walk and Red Clearance phases should add up to a duration of at least 17.5 seconds. MPO staff identified a Flashing Don’t Walk duration of 10 seconds and measured a four second Red Clearance phase, leaving the pedestrian crossing duration 3.5 seconds short. The current timing requires pedestrians to cross at a speed of 4.4 feet per second.

Similar to the Sufficient Crossing Time Index performance metric, the final three factors in the Safety category received moderate scores. There was one pedestrian crash at the intersection from 2015 through 2019, preventing the location from reaching the status of Highway Safety Improvement Program Pedestrian Crash Cluster, but the most effective intersections have zero crashes. The pedestrian signal phase at Linden Street’s intersection with Weston Road is exclusive. This allows pedestrians to cross safely without vehicular traffic obstructions but can require people walking to wait long periods of time to cross an intersection. It is important to note, however, that the unique nature of this location’s signalization and the speed with which the pedestrian phase begins after actuation work together to minimize the negative impacts of exclusive pedestrian phases at this intersection. Finally, the posted vehicle travel speed is 30 miles per hour, higher than the preferred 25 miles per hour, but not an excessive amount faster.

The Linden Street and Weston Road intersection received a “Good” score for System Preservation because the sidewalks at the location were all in decent condition and featured widths that meet or exceed the minimum five-foot requirement. Overall, the intersection was considered a Low Priority area for pedestrian transportation equity because only the proportion of one population at the location (elderly) exceeds the regional average, and the intersection is not located within one-quarter mile of a lower level school.

Bicycle Report Card

Figure 12
Bicycle Report Card for Linden Street and Weston Road

The intersection received a failing score for the Capacity Management and Mobility category of the Bicycle Report Card. This is entirely due to the fact that there are no bicycle facilities at the study location, which accounts for half of the overall category score. The intersection of Linden Street and Weston Road is a good candidate for bicycle facilities because it is located within one-quarter mile of other bicycle facilities on the Wellesley College campus and less than one-half mile from the Wellesley Square commuter rail station.

The intersection received another failing score in the Economic Vitality category, in this case because the location does not include bike racks. Yet again, this performance metric accounts for half of the overall category score, so the lack of safe places to secure bicycles negated the location’s positive score for land use. The residential buildings surrounding the study area indicate that there is potential for economic vitality near the intersection.

Linden Street’s intersection with Weston Road earned another failing score for the Safety category. The absence of bicycle facilities left the location with zero points for the associated performance metric. The intersection received 70 points for the Absence of Bicycle Crashes performance metric after a deduction of 30 points for the fatal bicycle crash at the location in 2012 noted in the Issues and Concerns portion of this study. Without bicycle facilities at the intersection, the location is not eligible to receive points for the Bicyclist Operating Space performance metric because people riding bicycles are required to share space with people driving, leaving them without dedicated operating space. Finally, the intersection received a score of 90 points for the Number of Travel Lanes performance metric. Weston Road only has one lane of travel in each direction and Linden Street only has one lane exiting the intersection. Ten points were deducted for Linden Street’s two lanes at its approach to the intersection. Unfortunately, this high score was not able to outweigh the intersection’s other considerable safety deficiencies for bicycle travel.

The intersection of Linden Street and Weston Road also failed the System Preservation category. This, once again, is a result of the lack of bicycle facilities at the study location. It is impossible to award points for bicycle facility continuity or condition without the presence of bicycle accommodations. Overall, the intersection was considered a Low Priority area for bicycle transportation equity because only the proportion of one population at the location (youth) exceeds the regional average, and the intersection is not located within one-quarter mile of a lower level school.

crash analysis

Crash Location Summaries

Crash Types and Times

Table 1 summarizes the 28 crashes from 2015–19 at the intersection of Linden Street and Weston Road. Rear-end crashes were the most frequent crash type at the study location, followed by angle crashes. Almost 68 percent of the crashes at Linden Street occurred during the AM and PM peak periods. Appendix A provides information about all 28 intersection crashes.

Crash Severity

There were no fatalities at the study location during the five-year period, although there were two injury crashes. Of these two crashes, one included injury to vehicle occupants while the other potentially injured a pedestrian. A total of one non-motorist, the pedestrian from the second injury crash, was involved in crashes from 2015–19 at the study location.

Table 1
2015–19 Crash Summary

Source: Central Transportation Planning Staff

Travel Direction and Improper Driving

Table 2 shows the total number of vehicles that were involved in the various crashes at the Linden Street and Weston Road intersection, characterizes each vehicle by the direction it was traveling, and identifies whether the police report indicated any improper driving. The police reports only noted a specific type of improper driving (including inattention) for 17 of the 35 involved vehicles at the study intersection. Crash data for the location indicate that 30 vehicles were traveling north or south on Weston Road compared with 22 traveling on Linden Street. Most of the involved vehicles on Linden Street were traveling west.

Table 2
2015–19 Crash Summary by Travel and Driver Errors:
28 Crashes; 52 Vehicles

Source: Central Transportation Planning Staff

Intersection Analysis

Travel Patterns

Massachusetts Department of Transportation (MassDOT) Highway Division’s Traffic Data Collection section collected traffic data for the study. Automatic traffic recorder (ATR) counts were collected during a seven-day period from Tuesday, November 16, 2021, to Monday, November 22, 2021. The ATR counts included daily traffic volumes and traffic mix (light and heavy vehicles). MassDOT also collected turning-movement counts (TMC) in the study area on Thursday, November 18, 2021, and Saturday, November 20, 2021. The TMC counts were performed during the weekday AM peak travel period (7:00 AM to 11:00 AM), weekday PM peak travel period (2:00 PM to 6:00 PM), and weekend midday period (10:00 AM to 2:00 PM). In all cases, passenger cars, heavy vehicles, pedestrians, and bicycles were recorded separately. The traffic data are included in Appendix B.

Turning movement counts for the weekday AM and PM peak travel periods are illustrated in Figure 13. The total average number of vehicles that passed through the Linden Street and Weston Road intersection on both weekdays and weekend days is documented in Figure 14.

Figure 13
Weekday Turning Movement Counts: Linden Street and Weston Road

Figure 14
Average Total Weekday and Weekend Vehicles: Linden Street
and Weston Road

The greatest share of traffic at the Linden Street and Weston Road intersection travels southbound along Weston Road, comprising 32.2 percent of the total volume. The remaining traffic from Weston Road’s southbound approach, comprising 10.7 percent of the total intersection volume, turns left onto Linden Street.

The smallest amount of traffic at the intersection comes from the Linden Street approach. Between the two options for travel at the eastern intersection leg, the greater amount of traffic turns right and travels northbound along Weston Road, making up 16.8 percent of total traffic. The smallest directional volume of the entire intersection, comprising 4.8 percent of all traffic at the location, turns left from Linden Street and travels southbound along Weston Road.

The remaining intersection traffic comes from the northbound Weston Road approach. Most vehicles continue straight along Weston Road northbound, comprising 28.2 percent of the total intersection traffic. The turning movement count data indicate that only 7.3 percent of all traffic at the Linden Street and Weston Road intersection turns right from Weston Road northbound to Linden Street eastbound.

Warrant Analysis

MPO staff conducted a signal warrant analysis for the intersection of Linden Street and Weston Road. Conditions at the study location satisfy the Manual of Uniform Traffic Control Devices (MUTCD) signal warrant analysis, meaning that the installation of a traffic control signal is justified at the location. The Highway Capacity Software Warrants Report is included in Appendix C. The intersection satisfies three of the MUTCD’s nine traffic signal warrants:

• Warrant 1, Eight-Hour Vehicular Volume
• Warrant 2, Four-Hour Vehicular Volume
• Warrant 3, Peak Hour

Intersection Levels of Service (LOS)

MPO staff conducted traffic operations analyses consistent with the Highway Capacity Manual (HCM) methodologies.5 HCM methodology is used to assess traffic conditions at signalized and unsignalized intersections and to rate the LOS from A to F. LOS A represents the best operating conditions (little to no delay), while LOS F represents the worst operating conditions (long delay). LOS E represents operating conditions at capacity (the limit of acceptable delay). Table 3 presents the control delays (standards for comparison) associated with each LOS for signalized and unsignalized intersections.

Table 3
Intersection Level of Service Criteria

Source: Highway Capacity Manual 2010.

Using Synchro traffic analysis software, MPO staff assessed the capacity and levels of service of Weston Road’s intersections with Central Street and Linden Street. Appendix D presents the existing conditions LOS analysis worksheets. Based on the traffic operations analyses, the intersection of Weston Road and Central Street has a LOS of F during the AM peak and a LOS of C during the PM peak. The Linden Street and Weston Road intersection is currently operating at a LOS of F during both the AM and PM peaks, operating under congested conditions with long queues during peak travel hours.

Signal Clearance Timing

To support the potential signalization of the study intersection, MPO staff calculated the amount of time traffic signals at Linden Street and Weston Road would need to allow for the yellow phase, red clearance, and pedestrian intervals. These calculations are included in Appendix E.

Improvement Recommendations

Short-Term Recommendations

One low-cost and quickly implementable change that would improve safety at the study intersection is painting narrower lane widths. By narrowing lane widths in the study area to 11 feet, people driving will travel at slower speeds, which reduces the severity of crashes.

This reduction in space allocated for vehicle travel lanes would allow Wellesley to additionally paint larger pedestrian zones on the east side of the Linden Street and Weston Road intersection. By designating more space for people walking, the distance which pedestrians need to cross when traveling through the intersection will be reduced. Extending the space for people walking will also increase drivers’ ability to see pedestrians as they prepare to cross the roadway. These conditions decrease the chances for pedestrian-vehicle collisions. Wellesley could increase the safety of these painted zones by installing large planters, flexible bollards, traffic cones, or moveable curbs to separate vehicles from people walking.

MPO staff analysis of travel patterns at the study location found it would be possible to reduce the curb radius with a larger pedestrian zone on the southeastern corner of the intersection. This is a result of the small number of heavy vehicles that turn onto Linden Street from the Weston Road northbound approach, which are the types of vehicles for which wider curb radii are designed. Of the 7.3 percent of the total intersection traffic that turns onto Linden Street from Weston Road northbound, 1.3 percent is made up of heavy vehicles like single-unit trucks, articulated trucks, and buses. This direction of travel has the smallest percentage of heavy vehicle traffic of the entire intersection. The majority of traffic (98.1 percent) turning right onto Linden Street from Weston Road is light vehicle traffic and the remaining 0.6 percent is made up of people bicycling.

Another short-term recommendation for the study intersection is to fully signalize the location. This would typically be considered a long-term improvement because traffic signals would need to be installed, but the intersection already features signal equipment. The signals themselves may need modification to feature all three light colors (red, yellow, and green), but this is relatively quickly achieved when compared to equipment installation. One key element that Wellesley would need to add to the current signals are yellow retroreflective borders to the signal backplates to increase visibility.

Using Synchro traffic analysis software, MPO staff determined optimal signal timings for Weston Road’s intersections with Linden Street and Central Street. Appendix F presents the LOS analysis worksheets for this low-cost recommendation. If the Linden Street intersection is pretimed and the Central Street intersection remains actuated and uncoordinated with other signals, traffic operations analyses indicate that the intersection of Weston Road and Central Street would improve during the AM peak period from LOS F to LOS C and during the PM peak period from LOS C to LOS B. The LOS at the Linden Street and Weston Road intersection under the same conditions would increase from an F to a D during both the AM and PM peak travel periods.

Finally, there are steps Wellesley could take to facilitate bicycle access to North 40 from the Wellesley Square Commercial District and Wellesley College. The stretch of the roadway along Weston Road between Linden Street and Central Street varies in width from approximately 30 to 33 feet. Narrowing Weston Road’s lanes to 10-foot widths leaves at least ten feet of space unaccounted for within the roadway between the two intersections. The National Association of City Transportation Officials recommends lane widths of 10 feet, explaining that they have a positive impact on street safety without negatively impacting traffic operations.6

To test the functionality and safety of allocating the extra space to non-vehicular uses, Wellesley could paint the excess roadway and add vertical separation similar to that used for the painted pedestrian zones proposed for the Linden Street intersection. Large planters, flexible bollards, traffic cones, or moveable curbs could be placed along the painted pavement area to separate the painted roadway from motorists. Studying the impact of this roadway design on vehicular travel patterns would allow Wellesley to determine the effect of allocating the extra space to people walking and bicycling.  

If Wellesley feels comfortable redistributing space from people driving to people bicycling and walking after observing driver travel behavior along Weston Road’s narrowed travel lanes, MPO staff recommend painting bicycle facilities along the roadway. Wellesley expressed a preference for shared-use paths instead of on-street bike lanes, but shared-use paths require funding and time to construct. To quickly test bicycle accommodations along the roadway segment, Wellesley could paint an interim shared-use path along the roadway. This would serve as a low-cost improvement until Wellesley is able to secure funding for shared-use path infrastructure.

The interim shared-use path would measure eight feet wide and should be accompanied by a buffer with a minimum two-foot width between the vehicle travel lanes and the interim shared-use path. In this scenario it would also be ideal to install vertical separation in the form of large planters, flexible bollards, traffic cones, or moveable curbs to provide additional protection for people bicycling. MPO staff also recommend including a bike box across Weston Road’s northbound approach to increase bicyclist visibility at the intersection and facilitate cyclists’ left turns toward Crosstown Trail and North 40.

Due to the reduced width of Weston Road north of the study intersection, MPO staff recommend adding signage to inform bicyclists and pedestrians they have reached the terminus of the shared-use path at Linden Street. Signage would also be needed to facilitate bicycle travel to Crosstown Trail and North 40 and support pedestrian wayfinding.

Figure 15 illustrates the proposed low-cost, short-term improvements to Linden Street’s intersection with Weston Road.

• Slow vehicle speeds by restriping the roadway and narrowing travel lanes to 11- and 10-feet wide.
• Using paint and temporary vertical separation, extend the sidewalks on the northeast and southeast corners of the intersection to create pedestrian zones that narrow crossing distances for and increase visibility of people walking.
• Fully signalize the intersection of Linden Street and Weston Road, adding yellow retroreflective borders to the existing signals’ backplates to increase their visibility.
• Using paint and temporary vertical separation, create an interim shared-use path on the east side of Weston Road between Linden Street and Central Street.
• Add signage at Linden Street that informs users that they have reached the shared-use path’s terminus and directs bicyclists and pedestrians to Crosstown Trail and North 40.

Figure 15
Low-Cost Intersection Improvements
Linden Street and Weston Road

Long-Term Recommendations

While the relatively low-cost and quickly implementable recommendations addressed above will improve safety and operations at the intersection of Linden Street and Weston Road, there are several additional improvements that Wellesley could consider. These additional recommendations are anticipated to require larger investments of time and money to implement.

Wellesley could invest in actuating the signals at the Linden Street and Weston Road intersection. Given the fact that Weston Road’s intersection with Central Street is already actuated, the town could optimize signal timing at both locations and increase LOS by coordinating the signals at the two intersections. Traffic operations analyses indicate that actuating and coordinating both locations would improve current conditions at the Weston Road and Central Street intersection from LOS F to LOS C during the AM peak and from LOS C to LOS B during the PM peak. The LOS at the Linden Street and Weston Road intersection would increase from an F under current AM and PM conditions to a B during both the AM and PM travel periods. The LOS analysis worksheets for these proposed conditions are presented in Appendix G.

If Wellesley finds conditions to be favorable after implementing the low-cost, short-term pedestrian zone and shared-use path recommendations, Wellesley could install concrete sidewalks with curbing and a vertically-separated, paved shared-use path to formalize the painted quick-build pedestrian and bicycle facilities implemented as short-term recommendations on the east side of the study intersection. This would provide permanent, vertical separation between motorists and people walking and bicycling between North 40 and the Wellesley Square Commercial District and Wellesley College. Wellesley’s future plans for the roadway and development in the intersection area should consider how best to ensure safe access to the shared-use path for bicyclists from Linden Street and Weston Road north of the intersection.

Finally, Wellesley could consider introducing additional roadway treatments to the intersection to reduce vehicular travel speeds. The Town has received complaints related to the noise created by vehicles driving over raised crosswalks, so vertical countermeasures may not be appropriate in Wellesley, but they are an effective treatment for speed reduction that could accompany the curb extensions recommended in this memo as horizontal countermeasures. Additional treatments to slow speeds that Wellesley could explore include chicanes and lateral shifts along Weston Road’s intersection approaches, although much of the existing roadway width is allocated to other uses through this memo’s recommendations.

Conclusions and Next Steps

Conclusions

There are several quick fixes that can be made at the intersection of Linden Street and Weston Road that have the potential to improve conditions for all road users. These rapidly implementable improvements can be accomplished using relatively affordable materials, which should keep the overall cost of the short-term updates low. If Wellesley finds that these intersection modifications yield positive results, the Town could consider allocating funds to construct more permanent versions of the projects to create lasting safety and comfort benefits for all who travel through the intersection.

Next Steps

The Town of Wellesley could begin its intersection improvements by implementing the signal timing recommendations documented in this memorandum. This should be accompanied by the roadway paint and striping recommendations to provide more space for and better visibility of people walking and bicycling through the intersection. Wellesley would need to determine which type of temporary vertical separation feels most appropriate for the study location and the Town as a whole.

Wellesley staff expressed interest in adding another lane to Weston Road’s southbound approach. This would create one southbound lane, one queue lane for left turns onto Linden Street, and one northbound lane. The impacts of this change on vehicular, bicycle, and pedestrian travel should be studied prior to adding a lane to the northern intersection leg, but it should be noted that the current roadway width of approximately 26 feet does not allow for three travel lanes. If Wellesley is able to expand the width of the roadway to accommodate an additional vehicular travel lane, the Town should look into whether additional space can be carved out to continue the recommended shared-use path northward along Weston Road. Bicycle accommodations should be prioritized corridor-wide, not just at the study intersection, and connectivity should be improved throughout Wellesley to improve safety, comfort, and utility for bicyclists.

Looking ahead at implementing the long-term study recommendations, the travel volume by mode and turning movement count data provided through this work may be used by Wellesley to complete applications for regional, state, and federal funding to support infrastructure improvements. If Wellesley is interested in constructing bicycle facilities within the study area, the town may consider applying for Community Connections Program funding through the Boston Region MPO.