How does the most heavily traveled interstate in Indiana get a face-lift and serve the needs of thousands of motorists at the same time? It takes years of planning, commitments to an aggressive construction schedule from everyone involved and a lineup of partners who understand the needs of the local community.
I-70 bisects Indiana on its cross-country trek and passes through the heart of downtown Indianapolis. The 6-mile stretch of I-70 from I-465 on the east side of the city to downtown is 30 years old. It is eight—sometimes 10—lanes across and carries 180,000 vehicles per day, making it the heaviest-traveled highway in Indiana.
The pavement has outlived its useful life. The Indiana Department of Transportation (INDOT) simply does not want to keep spending time and money patching the interstate any longer. Everything, from the concrete pavement to the bridge decks, is deteriorating faster than it can be fixed. I-70 was first constructed in the early 1970s and has been largely untouched since. A lane was added many years ago, but in most cases vehicles are driving on the same concrete and around the same narrow curves today as they were 30 years ago.
So, in a single construction season (March through November 2007) and at a cost of $175 million, Walsh Construction of LaPorte, Ind., will tear it all out and start over. Every inch of the old concrete between downtown Indianapolis and I-465 will go, with new, 16-in.-thick concrete replacing it from the ground up. It will be a brand new highway, and when this project is complete it will feature:
- 75 lane-miles of new pavement;
- 28 new bridge decks;
- 14-ft-wide inside shoulders;
- Improved drainage, signs and lighting;
- New traffic monitoring systems; and
- A filled-in underpass replaced by a towering overpass carrying I-70 over a city street and a railroad track.
Safe to say
Throughout the 6-mile stretch of interstate, there are three interchanges with on- and off-ramps in each direction. Because this stretch of urban interstate has become, over time, a commuter corridor, these ramps are extremely busy during morning and afternoon rush hours and contribute significantly to the volume of 180,000 vehicles per day.
To complete the bulk of the work in a single construction season, and to maximize safety for both workers and motorists, INDOT decided to close most of the ramps during both phases of construction. Indianapolis has an outer belt, I-465, that has enough available capacity to be used as an alternate route during construction. Indianapolis also is blessed with a network of city streets that serve as alternate routes for traffic normally using these ramps to get into or out of town on a regular basis.
But closing the ramps was not enough. Again, for safety reasons and to reduce the number of vehicles traveling through the construction zone, trucks heavier than 13 tons and all vehicles pulling trailers are detoured onto I-465 on each side of town. Indiana State Police troopers patrol the work zone continuously and issue costly citations to truck drivers who decide to take a chance on making it through despite the posted restrictions.
The final measure taken to ensure the safest environment for workers and traffic was the implementation of a reduced 45-mph speed limit. Prior to construction, posted speed limits on this stretch of I-70 were 55 mph, so traffic is not being forced to travel much slower than normal. Many motorists who continue to use I-70 have commented on how much smoother the traffic flow is, even if it moves a bit slower than before construction began.
To successfully complete the project in this short time frame, INDOT is working on one side of the interstate at a time. During the first phase of construction, scheduled through late June or early July, traffic is using the existing eastbound lanes while crews are rebuilding the westbound lanes.
Before construction, traffic used three or four lanes inbound and outbound. During construction, there are just three inbound lanes during the morning rush hour and two outbound. In the evening rush, the flow is reversed, with three outbound lanes and two inbound. To accomplish this, INDOT is using a moveable barrier wall.
A big part of the project’s success to date is because of that moveable center barrier wall from Barrier Systems Inc. INDOT used it to manage inbound and outbound traffic on a previous interstate project in Indianapolis, and opted to use it again on this massive project. The wall is moved 12 ft at a time from one lane to the other, providing an added lane in the peak travel direction.
Because of the 40% reduction in the number of available lanes, engineers estimated that at least 30% of the existing traffic (54,000 vehicles) would need to find alternate routes in order to minimize backups and delays within the construction zone. But where would they go? Traffic on I-465 around the south side of Indianapolis has increased nearly 20,000 vehicles per day since construction started. Those choosing not to travel through the construction zone or around the south side are using city streets as alternatives.
To help the city handle the extra load on its streets, INDOT funded more than $1 million worth of capacity improvements to roads and intersections on Indianapolis’ local street network, including street resurfacing, traffic-signal modernizations and improved traffic-signal timings. Other INDOT projects on interstates 70, 74 and 465 have added an additional $6 million worth of improvements to eastside streets over the last decade.
The maintenance of traffic scheme, reduced speed limits, truck restrictions and ramp closings have combined to help keep the construction zone as safe as possible. In fact, there are fewer accidents along this stretch of interstate now than when there were no restrictions in place. INDOT planners and the team from Walsh Construction are certainly pleased about the successes to date.
From March 1 to March 15 last year there were 16 property-damage and three personal-injury crashes. During this year’s construction, there were just five property-damage crashes and no personal-injury crashes during the same period.
Additionally, Indiana State Police troopers wrote more than 3,000 citations in the construction zone during the first several weeks of construction, and the truck restrictions have kept all but a few hundred of the usual 15,000 per day away from I-70.
Nearly in the middle of this 6-mile stretch is an underpass, sometimes called “the Cattle Chute” because of the feeling drivers experience as they dive down under Sherman Drive and a railroad line that goes over the highway. The underpass often is the victim of standing water, poor visibility and traffic slowdowns because of the dip and curve.
Because there is little property available on either side of the underpass to widen the interstate and improve visibility and drainage, INDOT decided to reconstruct I-70 over the city street and railroad to resolve the issues.
The surface of I-70 will be 50 ft higher than it is now, with traffic experiencing a slight reduction in elevation on either side of the approach to this section of interstate. While it is not an engineering marvel to turn an underpass into an overpass, it will be a significant change for drivers in Indianapolis, none of whom will miss the claustrophobic pinch of the Cattle Chute.
Something to discuss
Spreading the word about a project of this size requires a lot of advance planning and thought. This is the second major INDOT project where entrance and exit ramps have been closed through a lengthy construction zone. INDOT understands the project’s impacts on local traffic and businesses and is sensitive to both. Staff from the agency has worked for many months with the city of Indianapolis, public safety and emergency response personnel, businesses and neighborhood associations to explain the project, discuss the need and answer questions.
These meetings often led to the discussion of improvements to the existing maintenance of traffic plans necessary to rebuild the highway in this time frame and to maintain a safe corridor. Those ideas included providing more signage for hospitals, keeping an additional exit ramp open during construction when possible and offering technical assistance when requested, such as creating business-specific alternate route maps to those requesting them.
Informing trucking companies about vehicle restrictions, informing neighborhoods about ramp closings and helping businesses route delivery vehicles to their worksites were critical steps to ensuring success and safety.
INDOT placed signage several miles in each direction outside the city so inbound or through traffic would have ample warning about changes to traffic patterns and restrictions. INDOT even designed placemats for delivery to truck stops and restaurants around the state so drivers could learn about the project and plan alternate routes well in advance of their arrival in Indianapolis.
Following on the heels of the successful complete closure of I-65/I-70 through the center of Indianapolis back in 2003 (an effort called “Hyperfix” because of the innovative approach to rebuilding an urban interstate), INDOT knew it needed a catchy and recognizable name and identity associated with the project.
Because of the aggressive nature of the construction schedule, the substantial overall cost and impact and the fact this is the busiest section of interstate in Indiana, it was dubbed Super 70. The wings on the logo symbolize speed—something seen through the project thus far. The logo is used on all construction signage, outreach materials and the project’s website. It is something people would pay attention to and begin to associate with this project.
All of the materials INDOT has created for this project so far, including maps, signs, photos, alternate routes, project fact sheet, project scope and temporary parking and turn restrictions, are available now on the Super 70 website (www.super70.in.gov) and will remain there through the duration of the project.
Time for turkey?
Walsh Construction must be finished with the work on I-70 by Thanksgiving of this year. An early completion will earn the contractor a significant bonus, up to $1.8 million. If Walsh misses the deadline, it will be assessed damages of $120,000 per day.
Off-peak work will be necessary in 2008 to complete the overall project, but the huge impact to traffic will end this year.