Longfellow Bridge Notes 5/16/13- taken by Craig Kelley, Cambridge City Council. Please excuse any errors. You can get more official, if less elegantly written, information at the project’s website.
This project will start in July with the closure of the bridge to all outbound traffic (into Cambridge), the dropping of lanes two one inbound lane (into Boston) and bike, pedestrian and train access both ways. With the exception of 25 weekends during which the entire bridge will be closed (and T passengers bussed from Park to Kendall/Central), this will be the configuration of the bridge for the next 3.5 years- through September, 2016(after which it’ll be much the same as it is now, but with one lane coming into Cambridge, clearer bike lanes and wider sidewalks). Traffic from Boston to Cambridge will be detoured primarily over the Craigie Bridge and down Land Blvd or over the Mass Ave Bridge. There will also, at some point, be one week during which the pedestrian overpass to the river is unavailable as a new overpass is finalized.
MASSDOT is using design/build process, found a joint venture team to do the project that had its first meeting in April. They are looking forward to doing workshops with various stakeholders at a greater level of detail such as particular intersections, how police details will be used, cameras deployed, etc. They want to start moving in July, which is when the bridge will be shut (I am not sure if 1 July or later in the month).
Construction team is J.F. White, Skanska USA Civil Northeast and Consigli Construction in a joint venture. They are one of two entities that bid on this job. It is a design/build team that takes what DOT put together over the years and finishes it. The design team has a bunch of folks on it (employed by the Joint Venture) such as STV (lead designer), Tetra Tech (traffic management), Fortress (Emergency Preparedness) and a variety of other companies addressing public outreach, landscaping, historical concerns and so forth. They will have a variety of project managers, such as the folks in charge of the track work (entire Red Line stuff will be removed and replaced).
There is a youtube video demonstrating how the project will go forward.
This work is going to be massive. The bridge is going to be hugely demolished, with the road and steel and tracks and towers and sidewalks and railings and all that REMOVED and then either rebuilt new or rebuilt assembled. They will do the outbound work first, and then inbound with the train always running and always separated from rest of project. The trains’ running has an impact when other work might be done, as some work can only be done when train is not running. They’ll use temporary tracks for the trains as needed to allow work and traffic to proceed elsewhere. It’s worth watching the video to get an idea of how this is going to proceed.
They’ll put all sorts of info on the website, do lots of outreach efforts via email and social media, public meetings, etc. to keep people informed about the project. There will be a hotline set up in a month or so, along with a project email, prior to start of construction to accept complaints and suggestions.
This job needs to happen because the bridge’s structural integrity is dubious- arch ribs, spandrel columns, roadway deck, substructure and seismic restraints are all in need of work. All that steel needs to be fixed in this 100+ year old, oft-repaired bridge. It’s time for a major overhaul. Some will be repaired in place, some stuff will be removed but something like 90% of it will be impacted. Because of the bridge’s historic nature, such as the salt and pepper towers, special historic work and relevant review must be done. The towers will be removed, cleaned, brought back and reassembled on a new, improved foundation. Same with railings and so forth- repaired or replaced with replicas as appropriate.
On the Boston side there will be a new pedestrian bridge that goes over Storrow Drive to the Community Boating part of the River (it was on this bridge that I first saw my wife almost 23 years ago!). They’ll need to maintain navigable channel (recreational and commercial boats), ADA, compliance, biking and pedestrians’ access, etc. It is very complicated.
Needs to be done by 30 September, 2016 so they want to start soon.
Four phases, going left (upstream) to right (downstream, closest to MOS). Inbound is always to Boston. The four major phases have a total of 6 separate construction phases.
They are working with Boston and Cambridge to figure out traffic detours.
By Oct, 2015 the Red Line will be done, but there will be weekend work on 25 weekends (the bid allowed about 82) taking Red Line and vehicular traffic (with MBTA two way bussing) from Park Street to Central (not quite clear on this, perhaps just to Central). And they may also be stopping at State (Blue Line) which is actually handy. The T has protocols for this stuff, both planned and for emergencies, as far as where bus stops will be, etc. And if there is a T emergency that required the trains to stop, they’d quickly go to the two way busses and implement the detour the traffic as on the planned weekend shutdowns. They will be stopping in both the Kendall and Charles Street areas. During those weekends, the Bridge will be closed from Midnight on Friday to 5 AM on Monday and they’ll make sure they pick relatively uncomplicated weekends to do this closure work. Need extra space for trains to turn around, which is why Kendall and Charles are closed during these weekends as well. This allows for both track work and work that is too close to the track to be done without trains running and will take longer than 4 hour nightly shutdown. 5 closures in 2013, 7 in 2014, 12 in 2015 and 1 in 2016.
The traffic detour route will be signed and move folks through Leverett Circle across the Craigie Bridge and down Land Blvd, preceded by signage and special boards and what not to warn people ahead of time and highway message boards to avoid intersections and so forth. They’re obligated to sign specific routes for trucks and so forth. They have models that try to predict how people will switch their trips- what bridges and exits and so forth they’ll take, though the data is between 3 and 5 years old and don’t reflect other construction projects that have popped up since then. The Mass Ave and Craigie Bridges will take about 80-90% of the diverter traffic, with Craigie having the most. They think these studies are accurate and are based on the proposed construction limitations on the Longfellow Bridge. They have all sorts of info on river origins and destinations for Mass Ave Bridge, Longfellow Bridge and Craigie Bridge. Among other things, this shows that the Craigie Bridge carries a lot of folks coming off Route 93. They’ve taken the modeling down to an intersection level in the Lower Basin area. They can see where diverter traffic is going to take intersections to unacceptable levels and they use this info to shift focus onto Mass Ave and Craigie Street, not so much onto Broadway or Binney. Which in turn allows them to plan physical alterations to handle traffic flow, such as at Land Blvd, Charles Circle, Leverett Circle, Charles River Dam way and so forth for either physical alterations or traffic light changes. Other places will be viewed carefully to see if signal timing adjustments are needed, based on pre-project baseline info. They’ll use PTZ (Pan Tilt Zoom) cameras at a bunch of places for traffic monitoring. Boston already has a lot of cameras in their traffic operation center, with people monitoring them and making Real Time adjustments. Cambridge does not have cameras for traffic monitoring or the infrastructure required to use cameras for traffic monitoring, while Boston has dedicated fiber optics for that. They won’t have radar or ground traffic data collection systems. In Leverett Circle they’re going to have to manage traffic a bit differently to handle the extra flow, may change timing, etc. Putting in new set of lights, and an extra left turn lane at the end of Craigie Bridge at Land Boulevard. On the Cambridge side of things, they’ll be reworking some traffic flow to provide crossovers which will impact the median, etc.
Folks wanting real time traffic info will want to use Google Traffic.
There are a LOT of non-motorized trips across the Longfellow Bridge, so there is a real need to accommodate those users during this project.
There will be one week, at some point, when the pedestrian bridge to the river will be shut and various partial shutoffs around the way. But the replacement bridge will be built without more impact on the existing pedestrian bridge.
When the EZ-Ride busses run late, it can be a HUGE problem with scheduled 8 minute rides taking 30 minutes. And that’s BEFORE this bridge project starts. And other project are in the works that will impact the T. The project designers know this will be a fluid environment, but they don’t anticipate big, big, big problems. Even though a Binney Street construction project is going to start 15 June.
When the detour is implemented, they’ll look and drive the routes to see what the real impacts are and adjust as needed.
Stage 1, July 2013-August 2014, is for the inbound side of bridge along with some associated ramp and parking in Boston and on Cambridge side some island space for staging. So the weekday traffic then is a bike lane in each direction, one vehicle lane inbound only, pedestrian way and two way tracks. There will be closures to ramps on the Cambridge side to keep folks from getting on the bridge in the wrong direction. They’ll allow cars to get to Memorial Drive but not onto bridge. There will be a bike crosswalk as well.
On weekends when the bridge is closed, there will be bike share lanes with two directional buses. On those weekends, both outbound and inbound traffic must be detoured (inbound detour is still being worked on).
State 2- construction of temporary tracks, moving bikes and cars to the other side.
Stage 3- activate temporary tracks, rebuild MBTA inbound.
Stage 4- move tracks again, rebuild outbound tracks and general outbound roads, etc.
Stage 5- remove temp tracks
Stage 6- trains in final alignment, outbound.
Pinch points and dedicated bike lanes and so forth keep them from being able to have a lane of traffic all the time in each direction. Problem is that the Charles Street T station cuts into the roadway on the Boston side, it really hinders how cars and trucks can utilize the road here, knocks it down to 10.5 foot lanes. Doing that with busses, with professional drivers, might work for 26 weekends, but not for regular drivers on a daily basis. Putting bikes through the 3.5 mile detour to allow two way vehicular traffic would likely put them on the sidewalk across the bridge instead, with possible ped/bike conflicts as a result.
Inbound traffic proposed to be closed just during the 25 closure weekends. They’re still working with MBTA to figure out what those weekends will be, given other MBTA actions, but for this year, the weekends are the ones with the following Saturdays:
10 & 25 Aug
Last weekend Oct, 1st weekend Sept.
Subsequent years not worked out yet, waiting to see what happens with their 2013 requests.
BU bridge overpass work is hoped to be done by Sept 2013, but may going through rest of fall.
Every Monday, Cambridge DPW requires representatives from ALL ongoing construction projects to go to a coordination meeting, but the email and hotline should help fill in coordination/problem gaps that do arise.
They’ll use smart phone apps and other data gathering tools to figure out how long various routes take, to include a baseline measurement. That will help them figure out timing of signals and so forth. They won’t be providing this info in real time to drivers, just use the info to address issues. They’ll do the MassDOT.org thing to provide alternative routes and anticipated delays, but it’s not clear how precise they’ll be in telling folks how much time they’ll need to get to the airport, etc. So if that’s what worries you, or your customers, plan ahead and plan conservatively.
Three different police departments responsible for this work. Their traffic management work will include training with local law enforcement for incidents (through Fortress). They’ll run a live table-top exercise with various scenarios with consultants, contractors and law enforcement to clarify jurisdictional issues, communications protocols and so forth. Some concern that the Police on these details need to be paying attention to their work and be the ones who went through the relevant training (i.e. – not coming in from Lowell simply to fill a detail without some greater understanding of the detail’s relationship to overall traffic flow and safety).
Question: Three huge projects going on now- is July 2013 really a reasonable start date and what impact will that have on ‘customers.’ Reid Overpass, the bridge that carries Memorial Drive over the rotary at BU Bridge in Cambridge was an emergency job, Land Blvd/steam job was supposed to be done by June, but now it’s due to be finished in October. This was not planned for in Longfellow Bridge work but the contract has not been changed, so it starts in July.
The traffic impacts many intersections away are worrisome- will folks go through Somerville, jump through the West End? The project managers can’t really tell folks what to do. Modeling in 2008 and 2010 gave them origin and destination info, but they realize the busy streets are busy and they’re just trying to make best suggestions. Drivers will go where they go.
It seems unlikely that the T can add more trains should more folks decide to take the train (90,000 red line users per day already) to avoid detours and traffic. They’re trying to minimize amount of disruption, such as limited weekend closures. These impacts for 3.5 years are going to be tough and they could make the impacts less, but then the project would be much longer.