Office of Operations
21st Century Operations Using 21st Century Technologies

I-15 Reconstruction - Salt Lake City, UT

Types of TDM: Mode Choice, Route Choice, Time Choice, Trip Substitution Choice
Keywords: ATMS, design-build, special events, Olympics, 511, light rail, capacity enhancement, TOC
Area Demographics: Salt Lake City metropolitan area. Recent 7-year design-build reconstruction project of I-15 including significant investment in ATMS technology. The project was complete prior to the 2002 Winter Olympic Games.
Program: CommuterLink (TOC, control and field equipment), marketing and outreach during reconstruction, coordinated special events planning for the 2002 Winter Olympic Games.
Results: Commuter Link is expected to save Utah more than $100 million annually.
Cost of Programs: Reconstruction = $1.52 billion, Initial ATMS investment = $70 million.
Contact: Lawrence Jesse Glazer, FHWA,


Area Characteristics
The Utah Department of Transportation (UDOT) completed the 17 mile reconstruction of I-15 in July 2001. The project was completed in four and a half years at a cost of about $1.52 billion. Instead of rehabilitating segments of the highway, UDOT decided to rebuild the entire corridor. To meet an aggressive schedule and, in particular, aiming to finish construction before the 2002 Olympic Games, UDOT completed the project using a design/build approach.

The original I-15 infrastructure, built in the 1960’s, was designed to support half the traffic capacity it served in 1997. This capacity-enhancing project included adding two general purpose lanes, two high occupancy vehicle (HOV) lanes and auxiliary lanes between interchanges. Project components also improved access to downtown Salt Lake City, provided railroad grade-separations, replaced deficient bridges and utilized single-point interchange design. The project mitigated conflicting merging traffic movements and significant traffic congestion.

Program Description
UDOT recognized that the project would have significant consequences to traffic circulation and operations during all project stages. The contractor was required to maintain two lanes of traffic in each direction during peak commute periods as well as preserve critical freeway-to-freeway movements and access to downtown at all times. When interchanges and cross streets were closed, no two adjacent interchanges were inaccessible at the same time. Incident Management programs were expanded and supplemented by contractor-required courtesy patrols. As part of the reconstruction, emergency pullout locations were constructed along the corridor since limited shoulders were provided for disabled vehicles.

UDOT used a combination of demand-side strategies to maintain traffic during reconstruction. The ITS system (CommuterLink) was installed in three major pieces: 1) the Traffic Operations Center (TOC) including the physical building and internal networking equipment, 2) the control software, and 3) field equipment including VMS signs, cameras, and signal controllers. The comprehensive system includes a 511 Traveler Information Line, coordinated signals, ramp meters as well as speed, volume, weather and pavement sensors. UDOT installed the bulk of the $70 million worth of ATMS equipment using a design-build procurement method. CommuterLink was funded mostly by state funds ($52 million) with local ($1 million) and federal ($17 million) contributions.

ATMS technology enabled jurisdictions to monitor construction impacts, respond to traffic accidents faster, and communicate with the motoring public. The UDOT TOC is directly linked to both the Salt Lake City and Salt Lake County Traffic Control Centers and the Utah Transit Authority (UTA) Radio Center to provide seamless communication between jurisdictions.

UDOT also undertook a marketing campaign recognizing that one of the best ways to minimize traffic conflicts and delays on the interstate during reconstruction was to reduce the number of vehicles on the road. Employers and employees were encouraged to participate in ridesharing opportunities provided by UTA and commuter transit services, the Telecommuting Directive, and the Corridor Business Program. Informational services included the use of the internet, highway advisory radio, media outlets, signing, seminars and open houses. The importance of ridesharing and trip reduction was reiterated and promoted by such programs as Skip-a-Trip.

Evaluation of the 2002 Winter Olympic Games
The ATMS was put to the test for the 2002 Winter Olympic Games which was the largest Winter Games held to date. In total, the Games utilized twelve venues across the region. With 1.5 million tickets purchased, the travel needs were unprecedented. After the conclusion of the Games, an assessment was made on program components.

A number of goals and programs were established specifically for the Games TDM Plan depending on the venue and transportation user group. The two primary user groups considered were spectators and residents. For example, a specific TDM Plan goal was established to reduce background traffic by at least 20%. The strategies implemented to achieve this goal included transit, carpools, shifting work hours and travel routes and times. A follow-up survey with residents concluded that approximately one-fifth of residents changed travel patterns during the Games. Most residents offered that the change was related to an adjustment in daily work hours as opposed to a change in mode or route. In addition, a reduction in day-time truck traffic reduction between 30 -45% indicated by limited date from UDOT’s Automated Traffic Recorder (ATR) system also contributed to reducing background traffic. The Olympic Spectator Transportation System (OSTS) was developed to address the transportation needs of the spectator population and included 19 park and ride lots served by shuttle buses, the TRAX light rail system with overflow parking lots and publicly - subsidized shuttle services to mountain venues.

Athlete and media transportation needs were also identified and addressed. A shuttle service was created exclusively for 11,000 members of the media, which operated on fixed routes 24 hours a day. The Athlete Transportation System served 3,300 athletes and officials housed in Olympic Village. The System included over 500 passenger vans, 50 cargo vans, 44 coach buses which operated 24 hours a day. Both media and athlete services were encouraged to use alternate routes.

Measures of Effectiveness
CommuterLink has already demonstrated its effectiveness. During its first years of operation, CommuterLink has been attributed with the following successes:

• Increased peak hour freeway speeds by 20%,
• Decreased freeway delay by 36%,
• Decreased traffic signal stops by 15%, and
• Decreased Intersection delay by 27%.

Considering the efficiency measures above, CommuterLink is projected to save Utah more than $100 million annually.

An evaluation of the ATMS and TDM Plan components specifically for the Winter Games provide the following results:

• 80,000 unique visitors visited the CommuterLink web site during the Games,
• 511 Traveler Information line daily usage peaked near 4000 calls. By comparison, 511 usage on a typical day in 2002 was around 300 calls.
• Over 2.5 million passenger-trips were recorded on public transit during the Games.
• Park and ride shuttle buses carried one-third of the transit passenger trips.


Office of Operations