After 93 years of dedicated service, Milwaukee’s Sixth Street viaduct has retired. The 0.7-mi. (1.1 km) viaduct, which served as the primary connector of the city’s north and south sides since 1908, was demolished to make room for two unique, state-of-the-art cable-stayed structures, two bascule bridges and two approaches.
“The old bridge has served us well and is a civic and cultural landmark, but it is time to go,” said Leslie J. Fafard, Wisconsin Department of Transportation (WisDOT) southeast director.
Built in 1908 at the mere cost of $440,000, the viaduct encouraged economic growth and development of the city. Workers traveled its span on their way to meatpacking plants and tanneries. It also served as a platform for trolley cars and for the old North Shore rail line to Chicago. The rail tracks can still be seen on the driving surface of the viaduct, although the North Shore Line ended operations in the early 1960s. Trolley service was halted in the 1950s, but has been recently reintroduced by the Milwaukee County Transit System.
Dubbed an avenue of economic growth and a bridge between cultures, the viaduct provided a crossing that enabled a mixing of the different ethnic groups who settled the opposing regions of the city. Spanning the Menomonee Valley, it also bridged social divides in the old city, bringing downtown into contact with its ethnic heritage on the south side. In the Milwaukee Journal Sentinel, former Mayor Frank Zeidler described the viaduct as a gulf separating the city’s north and south sides and a “severe cultural dividing line.”
That Nearly Wasn’t
In spite of its significant contributions to the city’s economic and social welfare, the viaduct was unable to keep up with the times. Wear and tear from continued heavy usage wore out the aging structure. Traffic had been restricted to two of four lanes since 1998, and a weight limit was imposed years ago. The 15,000 vehicles served daily became part of a traffic bottleneck when lane closures clogged the flow of commuters. The viaduct’s concrete deck, steel members and supporting piers were in advanced stages of deterioration, warranting replacement.
But even as the old structure faced reduced capacity, the need for local traffic access continued to increase. The Menomonee River Valley has been slated as a key area for future urban development, and the near south side is home to a growing Hispanic residential and business community. With work on the massive Marquette Interchange into downtown Milwaukee scheduled to begin in 2004, the need for a detour route during that and other reconstruction projects played a key role in the timing of the project to replace the viaduct.
The need for a replacement of the viaduct has been plainly obvious for years. As far back as 1998, city engineers advised that the viaduct’s smaller support beams beneath the outer lanes were rusting, cracking, swelling, buckling and corroding.
According to a report in the Milwaukee Business Journal, a 1996 evaluation for structural soundness ranked the structure dangerously low. On a scale of zero to 100 — 100 being a rating for a new bridge and zero indicating a closed bridge — the Sixth Street bridge weighed in at 4.
Yet the obvious need to replace the failing structure nearly wasn’t enough to overcome the politics within the city, and served to hold up progress for years.
Mayor John Norquist and Gov. Tommy Thompson agreed that the viaduct was a critical path for the city, linking the Marquette interchange with the post office, Canal Street and Walker’s Point. They even agreed that it could act as a major thoroughfare to a redeveloped Menomonee River Valley, a feeder road around Miller Park baseball stadium, and a major route for Milwaukee County Transit Systems buses. Even the state budget recognized the need for replacing the structure, including funds in its biennial budget since 1989. But funds were not dispersed because the governor didn’t approve of the city’s proposed design, according to the Business Journal.
In 1991, the city and state signed an agreement affirming the city of Milwaukee as the lead agency. The city is responsible for the design and construction of the city-owned and maintained viaduct. The agreement further stipulated the funding split: 75 percent state funds, 12.5 percent county funds, and 12.5 city funds, all of which apply to the design, real estate and construction. The city also is responsible for maintaining the new structure.
The state DOT intended to let contracts to bid in November 1999, with construction scheduled to begin in 2000. The state had to move to Plan B when the scheduled letting was delayed because the city had not completed critical steps required by state and federal law before bridge replacement could commence.
An environmental assessment was not completed. The city is required to evaluate alternatives before the DOT can respond to a recommendation for replacement.
The city was slow to glean public opinion. An orderly process must be followed to ensure public involvement by holding meetings where citizens can voice opinions and ask questions.
Finally, although an agreement had been reached between city and state regarding funding, the Journal Sentinel reported that the state legislature was slow to approve it, further delaying the project.
At last, on October 27, 2000, Norquist, County Executive Tom Ament and Gov. Thompson joined to officially break ground on the new Sixth Street Viaduct. Funding was in place (including money from the federal Interstate Cost Estimate, or ICE), and the project had been turned over to Milwaukee Gateway Partners, a joint venture of Zenith Tech Inc., HNTB Corporation and Lunda Construction — all
Wisconsin-based companies. Representatives from WisDOT and the city of Milwaukee, Milwaukee County and the Federal Highway Administration formed a selection panel to review bids, awarding the contract to the joint venture, who submitted a bid of $49.7 million.
“I’m pleased this project has been put on a fast track and will come in under our projected costs,” said James C. Kaminski, Milwaukee’s commissioner of Public Works. “This structure will be an architectural landmark for the city, and become a main artery for the very vital Menomonee Valley.”
“The state is pleased to team with the city and county to ensure that the new bridge will be ready well before reconstruction of the Marquette Interchange begins in 2004, thus minimizing disruption to travelers,” added Fafard. “We are eager to see this important project get under way.”
The mayor expressed his delight, saying, “This bridge is going to be a hit with the people of Milwaukee. It will make reaching the Menomonee Valley much easier and it will become a striking symbol of the new economic spirit that’s alive and kicking in the Valley and on the near south side.”
What Goes Up …
The partners have two major project goals, said WisDOT Project Manager Aziz Aleiow: to open the viaduct to through-traffic as soon as possible, and to maintain the flow of traffic from the central post office from the west, while minimizing closure of the west entrance during reconstruction of the access ramps. While the entire project is scheduled to last about two years, traffic closures will be condensed into 15 months. The area closed to traffic on May 1. Demolition of the old bridge from South Canal to the south end of the viaduct was completed by June 8, Aleiow said.
“The Wisconsin Department of Transportation has worked closely with our partners to ensure the tightest possible schedule so that the new bridge will be in place in 2002,” said Gov. Thompson. Not only is the short-term inconvenience to Milwaukee residents minimized, but the new viaduct should enhance long-term value as well. It is the state’s first viaduct designed for a 75-year life span.
This project also is the first in the state to use a design and build process, which allows certain phases of design and construction to proceed simultaneously.
The team concept is a proven way to save costs; according to Aleiow, under a design/build concept, the team of individual contractors is led by an architect, all working together as one. The state legislature authorized the use of the design/build process as part of the 1999-2001 biennia budget bill.
Another first for the project is the introduction of cable-stayed bridges to the state. Cable-stayed bridges are supported by cables that fan from vertical piers, providing a sleek, sweeping appearance. The project will build two 80-ft. (24 m) wide, four-lane cable stayed structures, each with a double-leafed bascule bridge. Bascule bridges contain sections that can be tilted upward and away with a system of counterweights. Typically used on rivers where barges travel the waterways, they were used on the original viaduct.
Plans include a bicycle lane and sidewalks. The new viaduct will run south approximately 0.7 mi. (1.1 km) from Clybourn Street to Virginia Street, sloping down 900 ft. (274 m) on the north end, and sloping back up at the south end. An at-grade intersection with West Canal Street will replace the on- and off-ramps at mid-viaduct.
“The new structure will combine breathtaking aesthetic appeal with a direct connection to Canal Street,” said Mariano Schifalacqua, city commissioner of Public Works. City officials speculate that the innovative design shaved several million dollars off the project cost.
Twelve-story, 140-ft. (43 m) concrete pylons will support cables that stretch up to 205 ft. (62 m). The smallest cables are 0.6 in. (1.5 cm) in diameter, made up of steel strands, and weigh 11.5 lbs./ft. (5.2 kg/ft. carrying up to 250,000 lbs. (113,398 kg) of tension. The largest cables are 35 in. (89 cm) in diameter, weigh 34 lbs./ft. (15 kgs/ft.) and carry up to 870,000 lbs. (394,625 kg) of tension.
Project Manager Scott Piefer estimates that the project is 25 percent complete in the field, and 80 percent complete in the design, well on target to hit its scheduled completion date. Luckily, weather has not played a significant role so far this construction season. “Most of our rain has come at night,” noted Piefer.
“Rain doesn’t really hamper bridge work anyway. It’s not a factor.”
Portions of the project have two shifts working through Labor Day. The rest of the work isn’t “on a critical path with the schedule,” according to Piefer.
Currently in progress is foundation work for and construction of the north bridges. Demolition of the old structure and construction of the new bridges on the south side has yet to begin. Site preparation and relocation of utilities site-wide is ongoing.
Piefer said manpower on the job site hovers between 80 and 88, with 10 crawler cranes ranging from 50- to 150-ton (45 to 135 t), three backhoes and a barge fleet working off the water making up the machinery cavalcade.
He added that there have been few surprises. “It was a straightforward demo,” he confirmed. “We’ve run into some utility issues — relocation. But the biggest challenge has been real estate.”
Piefer explained that the partners took on the role of agent for the project, helping facilitate the purchase of the land by the federal highways commission, who will then turn it over to the city. “It’s a long, involved process,” he added, “with a lot of paperwork. This is an arena we aren’t used to working in, but we’re learning a lot.”
When completed, the viaduct will provide a new profile for the city, with its dramatic cable-stayed structures. “We’re hoping for beauty,” Piefer chuckled. “But these will be relatively small compared to many cable-stayed bridges. We think of them as our two little babies.”