Interstate 355
Interstate 355 (I-355), designated as the Veterans Memorial Tollway, is a 32.5-mile north–south controlled-access toll highway in northeastern Illinois that connects Interstate 80 in New Lenox to Interstate 290 near Itasca, traversing the southwestern and western suburbs of Chicago.[1][2] The highway, maintained by the Illinois State Toll Highway Authority, features six lanes for its entire length and employs open road tolling to facilitate uninterrupted traffic flow, a system it pioneered with I-PASS express lanes in 1999.[3][1] Originally opened as the North–South Tollway on December 24, 1989, between Interstates 55 and 290—a 20-mile segment designed to alleviate congestion on Illinois Route 53—the route underwent a significant southern extension of 12.5 miles to Interstate 80, completed on November 11, 2007, enhancing regional connectivity for commuters and freight movement.[2][1] This infrastructure investment has supported economic development in the corridor while integrating advanced toll collection technologies that reduce delays compared to traditional plaza-based systems.[3]History
Early planning and initial construction
Planning for a north-south tollway in the western Chicago suburbs originated amid rapid residential and industrial expansion during the 1960s and 1970s, which strained existing radial routes like I-55 and local arterials such as Illinois Route 53, a two-lane highway ill-equipped for surging suburb-to-suburb commuting.[4] Traffic volumes in northwest Cook and DuPage counties grew dramatically between 1972 and 1984, driven by population influx without sufficient north-south linkages, funneling vehicles onto overburdened east-west expressways and exacerbating bottlenecks at interchanges.[5] The Illinois State Toll Highway Authority identified the corridor—linking I-55 near Bolingbrook to I-290 near Itasca—as essential to provide direct connectivity, reducing reliance on congested parallels like IL 53.[6] In 1984, the Illinois legislature authorized construction of the North-South Tollway, enabling the Tollway Authority to proceed with funding sourced exclusively from toll revenues rather than state taxes, aligning with the agency's self-sustaining model established since its 1953 creation.[3] Groundbreaking followed shortly thereafter, with engineering focused on a 20-mile initial segment through DuPage and Will counties, incorporating four lanes total (two per direction) based on projections for moderate initial volumes amid ongoing suburban development.[3] This design prioritized efficient movement of commuters and freight, addressing causal gaps in regional infrastructure where east-west dominance had left north-south travel fragmented and delay-prone.[7] The project emphasized practical engineering groundwork, including alignments to minimize environmental impacts while maximizing capacity for projected daily traffic exceeding local road thresholds, though delays arose from land acquisition and opposition in the mid-1980s. By late 1988, substantial completion allowed testing, culminating in the tollway's operational readiness without federal interstate funding dependency, reflecting the Authority's autonomy in tollway expansions.[8]Opening of the northern segment
The original segment of Interstate 355, designated as the North-South Tollway, opened on December 24, 1989, spanning approximately 30 miles from its northern terminus at Interstate 290 near Itasca to its southern end at Interstate 55 near Bolingbrook.[2][9] This tolled facility marked the first limited-access north-south highway in the western Chicago suburbs, enabling direct suburb-to-suburb connectivity and diverting traffic from the overburdened two-lane Illinois Route 53.[7][10] Construction emphasized efficient capacity for forecasted commuter flows, with the Tollway Authority relying on extensive traffic surveys and counts from DuPage County intersections to justify the route's alignment and interchange placements.[10] The highway's opening immediately reduced reliance on local east-west arterials for cross-suburban travel, as drivers shifted to the controlled-access corridor, which featured six lanes and grade-separated junctions to minimize delays. Tolling began the next day at $1.00 per passenger vehicle, funding operations without initial state subsidies.[2] Early operational data indicated the segment handled projected volumes effectively, with the Tollway reporting subsequent improvements in travel times along relieved parallel routes like IL 53, where pre-opening congestion had routinely exceeded capacity during peak hours.[11] Accident reductions on those arterials followed, attributable to lower exposure on undivided roadways, though specific northern segment volumes remained below later extensions' peaks due to constrained terminal access.[11]Southern extension planning and buildout
The planning for the 12.5-mile southern extension of Interstate 355 from Interstate 55 to Interstate 80 spanned over a decade, originating in the mid-1990s amid growing regional traffic demands in Chicago's southwestern suburbs.[12] Initial proposals faced significant delays due to legal challenges concerning environmental impacts, including wetland preservation and the conversion of farmland for new roadway alignments.[12] These hurdles necessitated extensive environmental impact studies under the National Environmental Policy Act, documenting species like Blanding's turtles in the Des Plaines River Valley while evaluating mitigation strategies.[13] Construction approval aligned with the Illinois State Toll Highway Authority's adoption of a $5.3 billion long-range plan in September 2004, enabling groundbreaking and site preparation later that year, with full buildout commencing in December 2004.[14][12] The $730 million project featured innovative engineering, including the Des Plaines River Valley Bridge and alignments traversing primarily undeveloped farmland to minimize urban disruption.[15][16] Funding included a $380 million allocation in 2007 to finalize interchanges at I-55 and I-80, addressing prior funding shortfalls that had protracted the timeline.[17] The extension opened to traffic on November 11, 2007, providing a direct north-south corridor that diverted heavy truck volumes from congested local arterials such as U.S. Route 52.[18] This completion resolved earlier litigation through demonstrated regional benefits, including reduced overall congestion via empirical traffic modeling that prioritized net mobility gains over site-specific ecological trade-offs.[2] The buildout incorporated three lanes per direction, with provisions for future widening, marking the culmination of efforts to link I-355 seamlessly into the broader interstate network.[19]Renaming and subsequent modifications
In 2007, concurrent with the southern extension's completion, the Illinois Tollway renamed the entirety of Interstate 355 the Veterans Memorial Tollway to commemorate American military veterans, with the dedication occurring on Veterans Day, November 11. This rebranding entailed the installation of updated tollway signage bearing the new designation and the incorporation of veteran-honoring memorials, such as plaques at key points, while preserving the existing route configuration, lane counts, and interchanges.[3][20] Post-renaming, the Tollway pursued incremental rehabilitation efforts through the 2010s to address wear from growing usage, including a 17.5-mile road and bridge program featuring concrete pavement patching, median barrier height extensions for improved crash protection, and enhanced roadway lighting to boost nighttime visibility and energy efficiency. These upgrades responded to elevated truck and commuter volumes drawn by the extended corridor's connectivity to Interstates 55 and 80, which facilitated freight bypassing of congested urban arterials.[21] Additional minor enhancements targeted interchanges and ramps, such as repairs at Roosevelt Road to mitigate deterioration and improve flow amid induced commercial development in adjacent areas, though these did not involve capacity expansions beyond maintenance scopes. Traffic data from the period indicated steady volume increases, with the Tollway allocating $38.2 million in its 2008 capital budget specifically for the Veterans Memorial corridor to sustain operational reliability.[22][23]Engineering and design
Physical and operational specifications
Interstate 355 extends 32.5 miles from its southern terminus at Interstate 80 in New Lenox to its northern terminus at Interstate 290 near Itasca, comprising the entirety of the Veterans Memorial Tollway.[3] The highway maintains full access control throughout, with grade-separated interchanges and no at-grade intersections, adhering to Interstate standards for safety and efficiency.[24] The roadway configuration includes three lanes in each direction for a total of six lanes along most of its length, expanding to four lanes per direction (eight total) in higher-volume segments such as between 75th Street and U.S. Route 34.[3] [2] Posted speed limits reach 70 miles per hour for passenger vehicles from Interstate 55 southward to Interstate 80, with similar limits applying northward where conditions permit, reflecting engineering assessments of alignment and traffic flow.[25] [26] Pavement is primarily Portland cement concrete, constructed to thicknesses of 12 inches over an 8-inch subbase for durability under heavy loads, with maintenance protocols emphasizing periodic rehabilitation to sustain structural integrity.[2] Operational features incorporate intelligent transportation systems, including cameras, queue detection, and fiber optic networks for real-time monitoring of traffic volumes and incidents, enabling dynamic response to congestion.[27] Average daily traffic volumes, as tracked by the Illinois Tollway, typically range from 100,000 to over 150,000 vehicles in core segments, influencing design elements like shoulder widths and barrier warrants to handle truck traffic and peak demands.[28] These specifications support the highway's role in regional freight and commuter movement, with concrete surfacing selected for its resistance to rutting and longevity compared to asphalt alternatives in high-traffic toll environments.[22]Key infrastructure elements
The Des Plaines River Valley Bridge represents a primary engineering highlight of Interstate 355, consisting of two parallel post-tensioned concrete girder structures spanning the Des Plaines River valley near Lemont, Illinois.[29] Each structure measures approximately 6,600 feet in length, supported by 34 piers across 35 spans with maximum individual spans reaching 270 feet, enabling the bridge to traverse three rivers, two railroads, and three roadways while carrying six lanes of traffic.[30] The spliced-girder design facilitated these extended spans, reducing the number of piers and minimizing environmental and operational disruptions in the floodplain below, thereby enhancing flood resilience by elevating the roadway above potential inundation zones.[31] Interchanges at major junctions, such as those with I-80 to the south, I-55 centrally, and I-290 to the north, incorporate complex configurations including multiple flyover ramps to manage high-volume traffic flows efficiently.[16] At the I-55 interchange, for instance, the design features eight ramp movements supported by three flyover bridges, alongside mainline structures exceeding 350 feet, which integrate seamlessly with the existing expressway to reduce weaving and surface-level conflicts.[32] These elevated viaducts and overpasses, constructed to American Association of State Highway and Transportation Officials (AASHTO) Load and Resistance Factor Design (LRFD) specifications, provide resistance to wind loads prevalent in the region and accommodate seismic considerations through ductile detailing in substructures, ensuring structural integrity over the highway's operational lifespan.[33] Additional viaduct segments along the route employ similar elevated designs to cross rail lines, waterways, and urban developments without interrupting ground-level activities, as exemplified in the bridge's approach structures that blend into the broader corridor's geometry for smooth transitions.[30] These elements collectively enable Interstate 355 to function as a high-capacity north-south artery through densely developed suburbs, prioritizing minimal footprint in ecologically sensitive areas like river valleys.[31]Toll collection and revenue mechanisms
The Veterans Memorial Tollway (I-355) utilizes an all-electronic open-road tolling (ORT) system, featuring overhead gantries with transponder readers and license plate recognition cameras to collect tolls without requiring vehicles to stop.[34] This cashless approach, implemented across the Illinois Tollway system as part of reconstruction efforts starting in 2005, allows travel at highway speeds while capturing payments via I-PASS transponders or Pay By Plate for non-transponder users.[35] I-PASS accounts provide discounted rates, with passenger vehicle tolls for the full 32.5-mile corridor totaling $4.80, equivalent to approximately $0.15 per mile, while Pay By Plate incurs roughly double that amount at $9.60.[3] Rates vary by time of day—lower overnight from 10 p.m. to 6 a.m.—and by vehicle type, with trucks charged per axle and higher overall fees.[36] The tolling mechanism supports a self-financing model for the Illinois Tollway, where revenues exclusively from user fees fund construction, maintenance, operations, and debt service without state subsidies or taxes.[37] For I-355, this generates substantial income contributing to the system's annual toll revenues exceeding $1.3 billion as of 2022, with projections reaching $1.72 billion in 2025 amid rising traffic volumes.[38] [39] The 2007 southern extension significantly boosted revenue through increased usage, including truck traffic diversion from parallel freeways, as documented in Tollway traffic analyses.[9] Financial transparency is maintained through annual reports and independent audits, detailing revenue allocation and performance metrics for public oversight.[6]Route description
Northern and central segments
The northern terminus of Interstate 355, designated as the Veterans Memorial Tollway, is located at a partial cloverleaf interchange with Interstate 290 in Itasca, DuPage County, marking the beginning of this tolled north-south corridor through Chicago's western suburbs.[3] From this point, the highway proceeds southward, generally paralleling Illinois Route 53 to the east while providing a controlled-access alternative for regional travel.[3] The route serves as a primary artery connecting suburban office parks, residential communities, and commercial hubs in areas such as Schaumburg and Addison initially, before transitioning through more developed zones near Glen Ellyn and Downers Grove.[3] As it advances south through central DuPage County, I-355 intersects key east-west radials including U.S. Route 20 (Lake Street) and provides access to I-88 near Lisle, facilitating transfers to further western destinations.[3] The segment caters to high commuter volumes, with daily traffic exceeding 100,000 vehicles in peak areas during weekdays, driven by demand from nearby employment centers like those in Naperville's northern fringes.[3] Interchanges with local arterials, such as Roosevelt Road, enable connectivity to retail and institutional sites, while the six-lane configuration supports sustained speeds up to 65 mph.[3] Entering northern Will County, the central portion approaches the I-55 interchange near Bolingbrook, traversing a mix of suburban development and preserved open spaces amid flat glacial till plains that characterize the regional topography.[3][40] These low-relief landscapes, shaped by Pleistocene glaciations, feature minimal grades—typically under 2%—allowing efficient freight and passenger movement with limited vertical constraints.[41] The alignment avoids significant urban cores, instead interfacing with edge-city nodes that include logistics facilities and housing subdivisions, thereby supporting radial flows from O'Hare International Airport southward.[3]Southern extension
The southern extension of Interstate 355 comprises a 12.5-mile segment constructed between Interstate 55 near Bolingbrook and Interstate 80 near New Lenox in Will County, Illinois.[16] This addition, completed at a cost of $730 million, opened to traffic on November 11, 2007, providing a direct north-south link that bypasses congested local routes and enhances regional connectivity to industrial and commercial areas around Joliet.[15][42] Engineered as greenfield construction through largely undeveloped farmland and natural preserves, the extension avoids dense urban infrastructure by depressing the roadway beneath several overpasses for local arterials.[16] It features three lanes per direction, with a prominent 1.3-mile bridge spanning the Des Plaines River valley to maintain minimal environmental disruption in the rural-to-suburban corridor.[16] This design supports efficient freight and commuter flows, diverting volume from parallel county roads and thereby alleviating wear on secondary infrastructure in the pre-extension network.[43] The route's southern terminus at I-80 integrates I-355 into broader interstate travel patterns, facilitating access to east-west corridors serving Chicago's southwestern suburbs and beyond.[2] Post-opening analyses indicated up to a 20% reduction in regional travel times for affected trips, underscoring the extension's role in transitioning agricultural lands toward managed suburban growth without immediate overdevelopment pressures.[44]Exit list
The exits of Interstate 355 are enumerated below from north to south, with notations for partial or directional ramps based on official tollway documentation for the tolled segments.[45]| Exit | Destinations |
|---|---|
| — | I-290 east / IL 53 north – Chicago[46] |
| 31 | US 20 (Lake Street) – Itasca[47] |
| 29 | Army Trail Road – Addison (northbound off, southbound on) |
| 27 | IL 64 (North Avenue) – Lombard (northbound off, southbound on) |
| 24 | IL 38 (Roosevelt Road) – Lombard (northbound off, southbound on) |
| 22 | IL 56 (Butterfield Road) – Downers Grove (northbound off, southbound on) |
| 20 | I-88 (Ronald Reagan Memorial Tollway) – Aurora (northbound on, southbound off) |
| 20B | US 34 (Ogden Avenue) north – Naperville (northbound on, southbound off) |
| 19 | US 34 (Ogden Avenue) south – Lisle (northbound off, southbound on) |
| 18 | Maple Avenue – Downers Grove (northbound on, southbound off) |
| 17 | 63rd Street – Westmont (northbound on, southbound off) |
| 15 | 75th Street – Darien (northbound off, southbound on) |
| 13 | Boughton Road – Bolingbrook (northbound off, southbound on) |
| 12 | I-55 / Joliet Road – Chicago (northbound on, southbound off) |
| 8 | 127th Street – Lockport (northbound off, southbound on) |
| 7 | IL 171 (Archer Avenue) / 143rd Street – Lockport (northbound on, southbound off) |
| 4 | IL 7 (159th Street) – Orland Park (northbound off, southbound on) |
| 1 | US 6 (Southwest Highway) – New Lenox (northbound off, southbound on) |
| — | I-80 – Chicago, Iowa (southern terminus) |
Economic and regional impacts
Spurred development and job growth
The completion of Interstate 355's southern extension on November 11, 2007, connecting the existing northern segment to Interstate 80 over 12.5 miles through Will County, directly facilitated industrial and commercial expansion in previously underserved southwestern Chicago suburbs by providing efficient north-south freight access to intermodal hubs and O'Hare International Airport without traversing urban bottlenecks.[48] This infrastructure upgrade shifted development patterns toward lower-cost land in Will and adjacent counties, where ample parcels suited large-scale facilities, correlating with a surge in logistics-oriented projects as firms capitalized on reduced shipping times to Chicago markets.[49] Post-extension, the corridor attracted significant warehouse and distribution center construction, exemplified by the 1,400-acre I-355 Freight Cluster spanning Lockport and Homer Glen, which hosts multiple logistics operations leveraging direct Tollway ramps for truck access.[50] Developments such as the 355 Logistics Center and Heritage Crossing business park in Lockport emerged along the route, drawing tenants in warehousing and light manufacturing due to the extension's role in linking rural-industrial zones to regional supply chains.[51][52] Even prior to full opening, anticipation drove over 160 commercial buildings totaling 14.1 million square feet within a half-mile corridor, a trend that accelerated afterward as the highway enabled scalable operations on expansive sites unavailable closer to the urban core.[48] This access-driven growth empirically boosted local tax revenues and employment, with Will County's industrial base expanding to support logistics roles tied to e-commerce and distribution demands; the county's economic development authority notes the extension as a catalyst for sustained business influx, contributing to regional job gains in transportation-adjacent sectors.[53] By enabling outward migration of operations to affordable land, I-355 increased municipal tax bases through new property assessments on developed acreage, fostering fiscal stability for infrastructure-dependent suburbs without relying on congested alternate routes.[54]Traffic flow improvements and data
The southern extension of Interstate 355, completed on November 11, 2007, established a direct linkage between I-55 and I-80, offering freight haulers an alternative to the heavily congested Stevenson Expressway (I-55). This connectivity diverted substantial truck traffic from I-55, where pre-extension volumes often exceeded capacity during peaks, thereby alleviating bottlenecks in the southwest Chicago suburbs. Illinois Tollway transaction data from 2019 reflect 14,881 thousand commercial vehicle trips on I-355 annually, underscoring its role in freight redistribution.[9] Annual average daily traffic (AADT) on I-355 has grown significantly since its 1989 opening as the North-South Tollway, with systemwide totals rising from 116,106 vehicles in 1989 to 269,560 by 2024—a more than doubling despite regional induced demand pressures. Central segments, such as between Boughton Road and Maple Avenue, now handle 65,000–75,000 vehicles per direction daily, reflecting up to 250% growth in select high-volume areas from 1980s baselines while operating below the capacity of three-to-four lane configurations (typically 70,000–100,000 vehicles per direction at level-of-service C or better). This expansion has not saturated the corridor, as evidenced by Tollway performance metrics showing average peak-hour speeds of 55–70 mph across sections.[55][28] Empirical data from Tollway monitoring counter critiques of induced demand by demonstrating net congestion relief: the southern extension maintains near-free-flow conditions (0.0–0.2% congested travel, delays under 100 vehicle-hours per 1,000 vehicle-miles traveled), while central and northern segments experience only 1–4% congested travel during AM/PM peaks. Freight reliability has improved, with minimal bottlenecks supporting just-in-time logistics; for instance, peak-hour volumes at the I-55 interchange reach 5,600 vehicles but do not trigger widespread breakdowns. Tolls, dynamically priced via open-road systems, further optimize flow by discouraging non-essential trips during surges, unlike untolled parallels prone to overuse.[55][28]| Segment Example (2024 AADT per Direction) | Northbound | Southbound | Notes on Flow |
|---|---|---|---|
| I-55 to Boughton Road | 60,800 | 65,690 | Peak delays low; 1.9% congested travel |
| 75th Street to 63rd Street | 67,510 | 69,660 | Average PM speed 55 mph; freight corridor |
| Maple Avenue to Ogden Avenue | 76,880 | 76,880 | Highest volumes; tolls mitigate peaks |