The Infamous "Exit 17"

If you travel on the Mass Pike inside 128 you know it. Exit 17 is the exit for Newton Corner, as well as Watertown Square coming EASTBOUND from Metro West. Not only is the off ramp for this exit a disastrous design, backing up traffic trying to weave onto the roads of Newton, the backup around rush hour creates queues of cars along the eastbound side of the Mass Turnpike sometimes backing up traffic for more than a mile. And this is not a morning commute problem. In fact this off ramp tends to back up more often in the afternoon, than in the morning creating frustration among drivers who have just passed the Weston toll area. And the backup is not just for exiting traffic but for all traffic going east of the Mass Turnpike.

The problem is one that many Massachusetts roads are plagued by: A hard merge into an existing roadway without a good plan. The solution to this one is not as easy, because cars coming around Washington Street try to get far into the right lane to turn right onto Center Street. Some light may exist at the Church Street overpass where a left turn signal might actually make for an easier alternative than circling around the rotary and conflicting with off ramp traffic.

Boston University: BU Bridge/Commonwealth Ave

2018 NEWS: A light has been added at the end of University Road and Commonwealth Ave has been widened and better marked with lane indications. While this intersection is still challenging, these improvements have somewhat improved traffic and, most importantly, has reduced a bit of the risk at the University Ave crossing.

The reconstruction of the BU bridge was supposed to ease traffic, but it didn't. In fact, one of the poorest designs for an urban intersection is now one of the most dangerous and, in my opinion, is an accident waiting to happen and, unfortunately is most likely to be a case of a car hitting a pedestrian.

The primary problem occurs at point A on the map. Traffic coming off Carlton Street either must go straight onto University Road to enter Storrow Drive, or turn left onto Commonwealth Ave but to then get into the far right lane to cross the BU Bridge to Cambridge. Simultaneously, the right of way is afforded to the very heavy pedestrian traffic crossing University Road at point A. Cars simply end up backing up in the intersection as they wait for pedestrians. Meanwhile, cars trying to exit Storrow Drive, back up at Point A, waiting for a break in the pedestrian traffic. As a result, the short opening of time when they could safely turn onto Commonwealth Ave (which is just as the Commonwealth Ave light turns red, and just before the traffic from Carlton Street enters the roadway) is only occasionally free of pedestrians. As a result, cars and pedestrians jockey for an opening.

In fact, this very problematic intersection, which during BU Football games and Red Sox games can virtually reach a standstill, could be improved with two fairly inexpensive changes which would not force a redesign of the intersection:

1) The best solution would be a pedestrian tunnel underneath or bridge above University Ave. This would have the following advantages:

a) Protect the safety of pedestrians, including the thousands of students who live and attend school in the area.

b) Alleviate the timing problem created when the one open opportunity for traffic exiting Storrow Drive via University avenue, coincides with pedestrians wanting to cross. Thus more traffic could exit at the right time when Commonwealth Avenue is relatively clear.

c) Eliminate the jockeying that occurs when pedestrians and traffic fight for the right moment to cross.

2) The second best solution would be a pedestrian light across University Ave.

Either of these would improve safety, allow traffic to enter Commonwealth Ave from University at intervals which allow the greatest number of cars to flow, reducing backups that sometimes even backup Storrow Drive. In the absence of action, we are going to see cars running into each other on Commonwealth Ave in the right or second to right lane as well as pedestrians getting hit.

And MASS DOT solution to the whole problem? Yellow pedestrian signs!!

Leverett Connector

In spite of having won the July 2001 National Steel Bridge Alliance (NSBA) "prize bridge" Award, the Leverett connector has already earned its notoriety among commuters. Sometimes known as the "baby bridge" to the prominent Zakim Bridge, the Leverett connector connects Storrow Drive and Leverett Circle with the northern section of interstate 93 (and the Tobin Bridge as well).

Exiting Storrow Drive or Leverett Circle onto the connector is generally a good experience as the bridge quickly moves traffic out to the major northbound thoroughfares from the city.

However, coming southbound on I93 or off the Tobin Bridge, onto the Leverett Connector has become one of the worst traffic traps in the area. The connector, which is really just a huge two mile off ramp, does not allow southbound traffic to view its whole span when exiting I93 south. Additionally, GPS traffic does not cover traffic on the connector (we aren't sure why, exactly). Thus traffic entering this long ramp have no way to know if they will zip right through or if they will stand in a backup which could last up to the full 2+ miles and from which there is no alternative exit. And while this is disconcerting, the true flaw lies in the reasons for the often horrendous backups.

Why The Leverett Connector Downramp Backs Up

The connector moving southbound is set up for failure thanks to short sighted thinking about the design of the exit ramps. The right hand fork brings traffic to a light which does not adequately funnel traffic into the roadways. The light basically prepares one to cross an intersection, after which time they must wait in another light to either turn right towards Memorial Drive in Cambridge or go straight onto a narrow and tight merging Storrow Drive entrance. And because the right turn towards Cambridge then pits traffic against difficult turning signals and museum traffic, the off ramp fork just doesn't get you very far.

But the much bigger design flaw occurs at the left hand fork of the Leverett Connector off ramp where one lane only can get onto Storrow Drive and the majority of traffic using the Connector are using it to get onto Storrow. Now if this lane flowed freely then the connector might work, but the one lane of funneled traffic goes under a bridge and then must perform a hard merge with traffic on the right (ironically, coming off that right hand fork of the connector off ramp!). As a result, traffic cannot move quickly through the bridge and thus the connector left hand ramp crawls too slowly - backing up traffic at sometimes along the entire length of the connector.

Finally, to make matters even worse, traffic coming off the Southeast Expressway must make a hard merge right into this single lane that is being shared by two connector off ramps in order to stay on Storrow Drive west. Therefore, most of the day enjoys a bottleneck of merging, weaving and utter confusion - right across from Mass General Hospital.

So, what can be done other than redesigning the whole ramp system? One solution might be to limit traffic coming onto Storrow Drive from the Museum of Science (officially it's Nashua Street and McGrath Highway) and to not allow it to cross merge into the left hand lanes of Storrow. This would allow traffic flowing off the Leverett Connector to move into the right hand lane without a busy merge. Secondly, there needs to be clear signage at the end of the bridge, indicating which lane should be for which purpose. Massachusetts solution at best will be to throw a couple of HEAVY MERGE signs up and to let people fend for themselves, and as usual it will do nothing other than allow them to claim that they addressed the problem.

Woburn Massachusetts: I93/I95 Interchange

Anyone who lives or works north off the city, probably already knows the disaster awaiting them in Woburn where interstate 95 (aka Route 128) intersects with I93. The design problem here is a notorious one, where a tightly weaved cloverleaf creates a weaving pattern with traffic coming onto the roadway, and traffic trying to get into the far right lane to exit. Cars entering and exiting are forced to merge with each other into a single lane. Then cars which are entering the roadway, which have completed their merge, must now shift to the next left lane, virtually from a standstill to full highway speed.

This requires that there be no approaching cars, something that works fine during light traffic hours but which is nearly impossible during peak hours. Additionally, cars trying to exit, are held up moving to the ramp by these cars which are trying to shift left. Cloverleafs are so widely used because they are inexpensive, take up little space and require no stops or lights. A much more expensive and expansive solution, put into use in more recent decades is the flyover ramp as diagrammed to the right. Massachusetts installed a flyover ramp in Peabody, at the I95 (128) / Route One interchange but the lack of funding or space has hampered any further installations. States such as California and parts of Florida outside of the coastal areas, also have installed flyover ramps and Connecticut installed one right in East Hartford, adjacent to the city. The Woburn cloverleaf is responsible for a high number of I95/Rt128 backups going both directions at virtually any hour. While it does not typically back up I93, it does create danger and delays for those exiting or entering.

Mt. Auburn Street and Aberdeen Avenue in Cambridge

Perhaps best known for the location of the original Star Market, this intersection is also notorious for its dangerous and confusing configuration. This intersection literally requires one to have local knowledge in order to avoid an accident as neither logic nor sufficient signage are in use.

At the center of the matter is a bizarre U turn protocol taken by MBTA buses who are exiting Aberdeen Avenue at Mt. Auburn Street. Because of the location of the power lines above which the bus uses line a train rail for electric power, the bus must get into the far right lane and taken a U-turn straight in front of the other cars to get back onto Aberdeen going the other direction. And because the bus needs the full circle of the intersection to do it, it can only do it when Aberdeen has a green light (though it sometimes does it on red lights when the intersection has little traffic. This means that cars exiting Aberdeen Ave to turn left, and thus in the left hand lane, upon receiving a green light, might have a bus turning straight across their path. Generally the bus U-turn takes a full light cycle, leaving drivers on Aberdeen Ave confused unless they travel the route regularly.

Secondly, there is a problem with the timing of the lights, creating an even more dangerous high speed risk: Cars traveling Mount Auburn Street towards Memorial Drive must be in the far right lane to go straight. Bottlenecks arise in the left turn lane so drivers often shift over to the right or try to rush the light going straight. By the time this light turns red, a few cars are USUALLY in the intersection, and the Aberdeen light has already turned green. There is a high potential for cars wanting to gun the green light to turn left onto Aberdeen to be hit by a car rushing the Mt. Auburn Street light. This danger is exacerbated by the fact that they may have missed a green (because of the bus) or that the bus may be blocking their view.

There is actually a potential solution to this problem, which is surprisingly low cost:

1) Adjust the timing of the light (free)

2) Build a U-turn for the bus across the median of Aberdeen Road, a safe distance before the Mount Auburn Street intersection. And while this would require the hanging of some additional power lines, the relative cost to other road safety projects is fairly low, compared with the potential to improve the safety and flow of the intersection.

Action By the State DOT

Why then is there not action by the State DOT? Generally the problem is lack of funding for infrastructure projects and secondarily there are often problems with zoning and available space. This is why you will see similarly poor design in states like New York, near the city.

But beyond this, you also have traditionally low standards for roadways in the Commonwealth of Massachusetts, a kind of understood acceptance that we have bad/slow roadways.

Some I-95 Interchanges With Good Design

There are two exceptions worth noting among the thousands of poorly designed highways in Massachusetts, both coincidentally occurring at places where I-95 breaks from being part of the 128 beltway to continuing its worth as a north-south connector.

North of the city, the flyover ramp built from 128/95 northbound to direct continuing I-95 traffic north towards Newburyport is fairly well designed in this direction. Although the construction created massive delays as the roadway was temporarily detoured onto Route 1, the end result allows traffic to merge to the right early on and then funnels two lanes off and over 128 which goes on towards Peabody and Gloucester. Unfortunately, the same can't be said of the ramp which funnels traffic back onto 128 from I-95 coming from the north because that ramp dumps traffic into a weaving pattern with 128 southbound traffic trying to get onto Route 1.

On the south side of the city, you have two well designed ramps, one a flyover, which brings 128 traffic onto I-95 heading towards Providence.

What is sad is that traffic could actually improve with simple signage, both on the road side and painted into the lanes, which creates early warning reminders of which lane to be in for thru traffic and exiting traffic. Many of Boston's greatest highway bottlenecks come from exits which are full of weaving drivers. Still, signage is no replacement for proper design and although we do have a few ok ones here, the majority remains poor.

New design at the Burlington Mall offramp coming from I-95 southbound (that is, from Woburn to Burlington) allows traffic going up to Route 3 northbound towards Nashua to stay left and not wait in the same line as traffic exiting onto the Middlesex Turnpike. Perfect this is not, but it is a better plan than what originally was there.

Why Is the Southeast Expressway So Bad

Anyone who uses the southeast expressway between Boston and Braintree knows that this is one of the most insufficient arteries of any city in the US. The simple problem is that there are no major arteries moving traffic south of the city other than this highway and the southeast expressway must manage traffic:

- commuting from the southern suburbs

- going to and from Providence

- going to and from the Cape and the Islands

- going to the south shore

The expressway is simply too narrow to handle the traffic and as a result, fills up in both directions virtually throughout the day. And being a raised roadway, the Southeast Expressway has little chance of being widened a testament to some of the poorest advanced planning that I can recall as I review transportation systems.

The state has done what it can, adding HOV lanes and more rail service - but the reality is that Boston needs a highway linking the city with the 95/93 interchange in Westwood and unless we happen to come across an unused billion dollars, this is just not likely to happen.

Greater Boston Suburbs