CAJES Consulting (Centre move curbs)

Anthony Scotto, Clare Creedon, Emma Katz, Stacey Bacheller, Jesse Morrow


Figure 1: Location of study area

Centre Street is currently a main artery road in West Roxbury, Massachusetts as highlighted in Figure 1. It operates as a 30 mile per hour, distributor road for shopping and commercial traffic. The street essentially runs parallel to both the VFW Parkway and West Roxbury Parkway. Centre Street also connects to the major thoroughfare Washington Street, which then intersects I-95. The portion of the road that our project will be addressing spans from Lagrange Street to Belgrade Avenue. The major stores and attractions located on our street segment include: Walgreens, CVS, YMCA, Starbucks, and various national/local banks. Members of this community are continuously put at risk by the existing street design, but Centre Street has the potential to be a major local shopping center where shoppers can have a pleasant and safe experience.

Both North and South of Centre Street contains some of the highest population densities in the area. The median household income in the areas directly adjacent to our segment hover around $106,000, with West Roxbury as a whole ranking second in the Boston Area. Centre Street seems to be the closest shopping area for these high net worth individuals. CAJES believes that making these streets more pedestrian-friendly will tap into more of the high end market and enhance the shopping experience.

There are a significant number of children (under 18) and 30 year-olds residing just south of Centre Street, and many older groups reside to the West. With children present, elements for safe biking and driving become much more significant. Because of the high proportion of young adults in the neighborhood, it is very likely that bikes could become a more popular mode of transportation if safe and enjoyable bike facilities were built.




Figure 2: Existing condition of Centre Street (with parking)

Figure 3: Existing condition at signalized crossing

Figure 4: A man trying to cross four lanes on Centre St., as is today

Figure 5: Typical unsignalized pedestrian crossing

Centre Street is currently set up with two lanes going in each direction at unsignalized intersections (Figure 2) and up to five lanes at signalized intersections (Figure 3) , which is very hazardous for pedestrians attempting to cross. At a speed of 30 mph, the chance that the first car will stop for shoppers or residents is very minimal. Also, even if one or two cars do stop, there are still two more lanes that may be blocked from the pedestrian’s view (and pedestrians blocked from a driver’s view). We don’t expect pedestrians to step out into the road and assert their priority with the current design (Figure 4 and Figure 5). In 2015, a 10 year-old girl was dragged by a car exiting one of the shops on Centre Street and in 2007, a man was killed near the Corey Street intersection after being run over by a car. Two car collisions occurred within 15 days from one another on Centre Street in 2011. Because of these incidents, the school right off of Centre Street in the study area drew particular attention from our team to ensure their safety. Buses also travel on Centre Street, and will be given space, deducted from parking, in order to pull over without blocking traffic.

Upon reviewing satellite imagery and a few first hand accounts, CAJES came to the conclusion that the on-street parking is underutilized. This is due to the fact that most stores offer their own private parking lots to customers. There are also some minor developments occurring on Centre Street, mostly stemming from office conversions into condominiums. It is not believed that any planned or future developments on our segment could have a profound impact on street planning.


Proposed Design

Figure 6: Drawing of general proposed design and focused intersections

Centre Street is a 2+2 thoroughfare located in a commercialized area of West Roxbury. To address delays on this heavily used road, we will eliminate most signalized intersections with the intent to reduce the amount of queues. Due to issues with speeding and car accidents in a popular area, CAJES Consulting will redesign the entire street from Lagrange Street to Belgrade Avenue to enforce the recently changed speed limit of 25mph. The goal of our planning is to shift the priority to pedestrians and cyclists in order to reinvigorate this shopping district, while maintaining the same traffic volume served on this road previously.

There are a couple reasons why reducing the travel lanes on Centre St by half will not cause the egregious congestion that many Boston residents might expect, chief among them being the inefficiency of unprotected left turns.  With protected left turn lanes at the existing signalized intersections vehicles intending to turn left often back up in the left lane of the two travel lanes which essentially reduces the throughput at the intersection to the same volume of traffic that a single lane would have without interference from oncoming traffic.  Our redesign of Centre St removes 5 of 7 signalized intersections in order to lessen the stopping and starting of vehicles moving through, and the signalized intersections that remain have protected left turns to guarantee greater throughput. We also ruled out the use of bike lanes on our road segment given the high traffic volume, as per NACTO recommendations, and will instead be proposing separated cycle tracks.

Typical Cross Section

Figure 7: Typical cross section of Centre St redesign

The typical cross section view of our Centre St redesign, Figure 7, radically changes how the 80 feet from storefront to storefront is utilized, giving much greater preference and visibility to cyclists and pedestrians.  We have reduced the street from 2+2 travel lanes to 1+1 travel lanes, and also reduced the width of the lanes from 11 feet to 10 feet to encourage slower speeds.  It is important to note, however, that this space is still available to the lanes in the form of a 2 foot cobblestone median which can be mounted by vehicles if the need for more space arises. The mountable median will enforce drivers to stay in their lane but also give drivers flexibility if emergency vehicles or delivery trucks need to get through.  

We have included a row of on-street parking on each side of Centre St in almost all places where it existed previously because this neighborhood has a lot of shops which we want to keep accessible to all patrons.  Additionally the parking and departing vehicles along the street will further slow thru traffic and increase awareness of drivers traveling through Centre Street.  Between the rows of parking and the new cycle tracks is a curbed buffer space of 5’ which will accommodate a row of trees and streetlights.  The cycle tracks are one-way on each side of the road and 6’ in width to allow for side by side cyclists at most times (with overhang space on either side of the cycle track).  The sidewalks between the cycle tracks and storefronts will remain 10’ which provides ample space for outdoor seating or displays to liven up the neighborhood.  We believe that this redesign will create a more accessible and appealing area, while also providing safer facilities to the cyclists and pedestrians that are naturally more vulnerable to vehicle traffic.  


Figure 8: Example of Dutch road used to influence our design

Our redesign of Centre St is designed to meet two seemingly contrary purposes: to make it safer for crossing pedestrians and cyclists, and to maintain the same volume of through traffic as before. We believe this is possible because the town of Delft has succeeded in such an experiment with the road diet applied to Ruys De Beerenbrouckstraat, as seen in Figure 8. This road carries a high volume of through traffic but lowers the maximum speed of vehicles while maintaining crossability with just one lane per direction. One neat feature on Ruys De Beerenbrouckstraat is the use of cobblestone paving (both for a 2’ center median and a 1’ drainage slope at the curb) in order to make each travel lanes width appear smaller.  This is the reason why our redesign of Centre St includes a 2’ cobblestone median as well, which is perfectly fine for vehicles to ride on when necessary, but mostly will be avoided because it is uncomfortable for the driver.


Bus Stops

Figure 9: Cross section of redesign at bus stop

An important consideration in our redesign of Centre St is how to accommodate the city buses that make approximately 15 stops on our section of Centre St at a frequency of 8-15 minutes.  Although the Dutch guidelines are moving in the direction of having buses stop in the travel lane rather than pulling into a bus bay out of the way of traffic, we have decided that the high number of stops along this route requires buses to pull out of the travel lane.  In order to have space for wide buses to pull in and out of a bus bay, we have reduced the lane widths of the thru travelling lanes to 9 feet each with only a 1 foot cobblestone median in between.  Another important change from our typical cross section is the expanded sidewalk and transit shelter built into the buffer space between the road and the cycle track.  We believe it is important to give bus riders loading and unloading room close to the bus bay that doesn’t force them to immediately step across the cycle track while bicycles cycle quickly by.


Pedestrian Crossings

Figure 10: Aerial view and current measurements of pedestrian crosswalk

Figure 11: Proposed pedestrian crossing between Quinn Way and Mt. Vernon St.

Figure 12: Street view of narrow lanes and wide median at pedestrian crossing

At unsignalized pedestrian crossings and intersections, our redesign includes important design features to guarantee the ease and safety with which pedestrians can get to the other side of the street.  Shown in Figure 10 is a critical crosswalk used by pedestrians traveling to Walgreens as well as children walking to the Patrick Lyndon Elementary School on Mt. Vernon Street.  The current situation forces children to cross four lanes at once.  This is incredibly dangerous because we are expecting cars to yield to pedestrians where the current design gives every indication that it is okay to drive fast.  We have found inspiration in Dutch roads that allow for medium to high speed thru traffic while still maintaining their “crossability” with only one lane of traffic to assess and cross at a time.  At pedestrian crossings, we have included a large curbed crossing median tapering up to 8 feet in the middle of our travel lanes, providing an island of refuge for pedestrians (Figure 11).  Even with faster travelling vehicles, a pedestrian is much safer when they only need to watch for a window in oncoming traffic in one lane rather than two or more.  As the travel lanes approach the pedestrian crossing, the width is reduced from 10’ to 9’ and the center median of 2’ expands to an 8’ curbed median.  Both of these measures are intended to slow thru vehicles by pinching the space they can use and preventing them from driving in a straight line.  The crosswalk area is also indicated by both painted lines and raised red brick to alert drivers they are entering a pedestrian crossing zone.  

We’ve proposed a curbed buffer space next to the cycle track that swells on both sides of the road to encompass the parking row, thereby reducing the actual distance and time that pedestrians must be stepping on the road (Figure 11).  We have dedicated the extra sidewalk space leading up to the pedestrian crossings to bicycle parking facilities, which are a necessary feature to include when hoping to revitalize cycling accessibility in a neighborhood.

Figure 13: Example of table crossing

As mentioned previously, the safety of the school children and shoppers alike is our top priority. We plan on embodying typical Dutch raised table crossings on our segment. Raised crossings like the one shown in Figure 13 work by keeping pedestrians at sidewalk level, even when in the road. This increases visibility, especially for children, and demonstrates their priority. The table crossing also works to reduce car speed by acting as a gradual speed hump and simply as an attention grabber. We understand that this road is a distributor, but keeping speeds at 25 MPH is the goal. The table crossing will be designed so that cars need not come to a full stop, but rather can proceed comfortably at 25 MPH.

Crossing tables will be inserted at Redlands Road, Willow Street, Maple Street, Hastings Street, and Richwood Street. These streets are unsignalized and have the necessary commercial traffic to justify having a raised crossing. The crossing tables will have red bricks that extend far enough into each intersecting street to warn drivers that they are entering a pedestrian zone. Both Quinn Way and Esther Road are unsignalized but do not have the commercial traffic to justify inserting a table crossing. For all signalized crossings, we believe that inserting raised crossings would not pose a substantial benefit, as cars have to stop for the light.


Private Driveways and Parking Lots

Figure 14: Aerial of Walgreens parking lot on Centre St.

Figure 15: Example of left-turn pocket in the Netherlands

Figure 16: Proposed street plan for Walgreens entrance

Figure 17: Street view of left turn lane appearing at parking lot entrance

Travelling North from the Lagrange Street intersection, the first point of interest for redesign is the area surrounding the Walgreens parking lot. Cars traveling along Centre Street are allowed to turn into the parking lot with both right and left turns, but this can slow down thru travelling traffic as vehicles wait to make the turn.  When reducing a road from 2+2 to 1+1, it is very important to ensure that thru traffic can flow continuously and there are no major bottlenecks. Since there are no passing lanes, people must be able to easily continue straight on Centre Street despite cars turning right or left at an unsignalized intersection or a private lot.  In the new design shown in Figure 16, Centre Street has been reduced to 1+1 travel lanes with a left lane turning pocket.  The left lane turning pocket inspired by the Dutch street in Figure 15 gives cars wanting to turn left into the parking lot an area to wait and decide when it is safe to cross oncoming traffic.  The waiting area is the solution for allowing thru traffic to continue traveling straight as they are not forced to slow down or move over to the right lane as they do in the existing conditions.  Another important design feature in the new plan is the waiting area for cars entering the parking lot.  Since the new design incorporates one-way cycle tracks, the cars should have an area to wait to decide if it is safe to cross the bicyclists and pedestrians zones.  In addition, the waiting area forces right-turning cars to make a 90 degree turn towards the cyclists making it easier for drivers to see potential conflicts.

On Ruys de Beerenbrouckstraat (see Figure 8), CAJES Consulting found inspiration for a wiggle in the cycle track at the raised table crossings and “forced” 90 degree turn. The pedestrian crossing in front of the Albert Heijn is slightly raised, which accomplishes the goal of raising pedestrians to eye level. The aspect of this crossing that makes it unique is the grade of the incline and decline of the hump. It is gradual enough so that cars have to slightly slow down, yet through traffic is not significantly impacted. One can also see the receding sidewalk and cycle track at the right hand turn. There is enough room so that by the time the car passes the cycle track and sidewalk, it is at a 90 degree angle. There is also a median that extends into a raised median at the crosswalk. This successfully both protects pedestrians while crossing and narrows the roads to reduce speeds.


Redlands Road at Centre Street

Figure 18: Aerial view of Redlands Rd. and Centre St Intersection

Redlands Road is a local, residential road. As shown in Figure 18, it connects to Centre Street at a 45 degree angle to create a tee. This stray from perpendicularity increases risks of accidents. A car driving west on Centre St and turning onto Redlands Rd is not likely to slow down due to an easy, slightly curved turn. If a bicyclist is coming from the right and goes to cross this intersection, the car turning will not be going slow enough to stop.

Figure 19: Ruys de Beerenbrouckstraat’s features will be used in Redlands Rd Redesign

As shown in figure 19, Ruys de Beerenbroucktraat exemplifies pinched roads and medians at crossing areas. Their crossings have red bricks to alert drivers to be cautious of crosswalkers. There is a waiting space in this photo that we will incorporate into our street design. The corner safety island will slow cars turning right from the side street.

Figure 20: Proposed plan for Redlands Rd.

Redlands Road is one-way residential road and doesn’t connect to any major streets, so it is assumed that it has low-traffic. Therefore, crossings will be easier at this intersection. Cyclists turning left onto Redlands Road will share the crosswalks with pedestrians. We have taken parking away from this intersection at 30 feet on each side of the crossings based on NACTO’s recommendation regarding one way cycle tracks at intersections.

In order to prevent cars turning at fast speeds onto Redlands Road and to improve their visibility of the existing crosswalk, we will change the Southern part of Redlands Rd to be completely perpendicular to Centre St, shown in Figure 20. We will also extend the sidewalk 10 feet to force cars to significantly slow their speeds to almost a halt before turning onto the local road. The extension of the sidewalk acts in a similar way that the corner safety island does in Figure 19 to slow turning cars.

We strongly believe in the 8 80 philosophy of making streets liveable and accessible for all ages. We think this is necessary to connect shops on both sides of Centre Street to assist elderly people living at the Redlands Road Nursing Home as well as other people trying to cross the street. The crosswalk section of the road will be pinched to narrow lanes and reduce speeds. A concrete median of 8 feet will also protect and assist pedestrians as they try to cross traffic. As for livability, we will increase vegetation along the 5 foot space we have between cycle tracks and the roads.


Typical Unsignalized Intersection

Figure 21: Aerial view of Corey St. intersection

Figure 22: Proposed plan for typical unsignalized intersection. (Corey St.)

Corey Street is a high volume, signalized road. Destinations at this intersection include churches, shops, and a bank. To alleviate frequent delays, we propose to remove traffic lights and use stop signs for drivers entering Centre St from Corey St as shown in Figure 22.  Our redesign of this intersection focuses on reducing vehicle speeds to ensure safety and ease for crossing pedestrians and turning cyclists. The new six foot medians between cycle tracks and traffic and pedestrian waiting areas will act as a barrier between pedestrians and traffic and allow a standing area if needed. The pedestrian waiting areas for crossing on the sidewalk will extend outward to pinch the roads with the median. With less lanes to cross at a time, levels of risk go down. We will extend the brick pavers further on Centre St to warn cars before entering the crosswalk that they are entering a zone where pedestrians are vulnerable.

Similar to Figure 15 where a left turn pocket allows for a more continuous flow of traffic, we have designed the typical unsignalized intersection like Corey St to have room for a left turning vehicle to wait in the middle where thru travelling vehicles can pass on the outside.  We believe that slower vehicle speeds does not need to come at the expense of high congestion and delays, in agreeance of the Dutch principle of “drive slower to get there sooner.”  For this reason our redesign of Centre St demotes five signalized intersections to unsignalized intersections where the flow of traffic and crossing pedestrians can be responsive to the vehicles and humans around them.  


Signalized Intersections

Figure 23: Plan view of Centre St. and Lagrange St. before redesign

Figure 24: Proposed plan for typical signalized intersection (Lagrange St.)


Figure 25: Street view of turning lanes at signalized intersection (Lagrange St.)

The intersection of Centre St and Lagrange St is one of the bookends for our street section redesign, and also happens to be our highest volume traffic intersection with many Northbound and Southbound turns onto Centre St.  Although our solution for accommodating cyclists and pedestrians in this shopping district is to give Centre St a road diet by shrinking 2+2 lanes down to 1+1, it is important to recognize where additional lanes are necessary to allow a steady flow of traffic and prevent congestion.  Therefore at the intersections along this stretch of Centre St that will remain signalized in our redesign (Lagrange St and Belgrade Ave) we have abided by the Dutch philosophy of “skinny roads and wide nodes.”

Whereas less travel lanes across a street encourage slower speeds for vehicles and make the street much more crossable for pedestrians, it is an important safety measure to include left turn lanes and right turn lanes at a signalized intersection both for the safety of cyclists and drivers.  When a vehicle is making a left turn, there are multiple hazards that command their close attention while they feel the pressure of cars backed up behind them: finding a window in oncoming traffic, inching their way into the middle of the intersection while paying attention traffic signal, and watching for pedestrians and cyclists in the crosswalk.  This situation is particularly dangerous for cyclists travelling straight through the intersection quickly on a cycle track, where the driver turning left across the cycle track may not see them until it is too late.  By providing a left turn lane with a separate signal phase as shown in Figures 24 and 25, as well as bicycle/pedestrian signals that prevent them from crossing at the same time, these hazards can be greatly reduced.  It is also important to include a right turn lane separate from the through travelling lane, so that vehicles are not pressured into a right turn across a bicycle/pedestrian crossing by the cars behind them but rather have time to slow down and wait for anyone that may be in the crosswalk.  

Along with the turning lanes for vehicles, our redesign of the Lagrange St intersection includes subtler elements that will further increase the safety of cyclists and pedestrians.  Chief among these are the curbed corner safety islands which jut out from the cycle track turning area, forcing cars to take a wider turn when turning right or left.  These corner islands also help provide cyclists with a waiting area on the cycle track before their crossing signal turns green- which is important because cyclists hoping to turn left will have to make a two stage left first moving straight across the intersection and then making a left turn and crossing the intersection again.  The curbed corner islands provide left turning cyclists room so that they do not block cyclists wanting to continue straight past the intersection.


Additional Suggestions

In order to make this design work its best, there’s additional work to the general road design that should be done. Some of these include a reevaluation of signal timings to account for less signalized intersections over the study area. Additionally, it may be helpful to evaluate the effectiveness of the direction of the driveways and roads that intersect Centre Street as there may be some roads and driveways that may be more efficient becoming one way or turned from one way to two way. With adding the table crossings to some of the intersections, drainage also needs to be considered. Because there will be a gradual incline leading up to the intersection and a gradual decline from the intersection, it’s likely that water could pool in the intersection or at the incline.  The table intersection should be designed in a manner to address this potential issue.


Cost Analysis

Bike policy can be controversial as most people drive cars and are uncomfortable with change.  For government officials, gaining popularity means avoiding difficult changes although it may be better long-term. Fortunately, bicycle infrastructure has a low operating cost compared to roadways.  A study by PeopleForBikes found 1 mile of protected bike lanes to be 100x cheaper than 1 mile of roadway.  Essentially, bicycles are lightweight and the construction required for bicycle facilities is lighter than road/highway construction.  


In conclusion, we implemented drastic changes to Centre Street in order to accomplish our goals. We shifted priority from cars to pedestrians by both removing a driving lane in each direction so that people only have to cross one lane at a time unless the intersection is signaled. CAJES consulting also added raised pedestrian crossings to demonstrate the shopper’s and resident’s priority. We increased driving safety by eliminating the option to pass, and narrowing the roads to reduce speeds. Ultimately, Centre Street still needs to be able to function as a distributor road for both residents and commercial traffic alike. Therefore, we implemented the narrow road and wide node practice, so that there is no turning congestion. We also eliminated five traffic lights, as to allow thru traffic to flow freely, especially in peak times.



Street Design Rendering:
Streetmix. N.p., n.d. Web. 16 July 2017.

Redesign Guidelines:
Ink, Social. “Home.” National Association of City Transportation Officials. N.p., n.d. Web. 16 July 2017.

Street Photos:
Google Maps. N.p., n.d. Web. 16 July 2017.

West Roxbury Demographics:
“Overview of West Roxbury, Boston, Massachusetts (Neighborhood).” Overview of West Roxbury, Boston, Massachusetts (Neighborhood) – Statistical Atlas. N.p., n.d. Web. 16 July 2017.

Centre Street Accidents:
Google Groups. Google, n.d. Web. 16 July 2017.