Mahoning Avenue Viaduct

The Mahoning Avenue Viaduct carries Mahoning Avenue over the Shenango River and adjacent railroad lines in New Castle, Pennsylvania.

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The Mahoning Avenue Viaduct carries Mahoning Avenue over the Shenango River and adjacent railroad lines in New Castle, Pennsylvania. Constructed between 1923 and 1924, it replaced the earlier Gardner Avenue Bridge, built circa 1890 and destroyed during the catastrophic flood of 1913.

History

Gardner Avenue Bridge

The Gardner Avenue Bridge over the Shenango River was constructed in 1890 to connect New Castle with the city’s Seventh Ward (Mahoningtown) and Eighth Ward. ^{3 7} The crossing consisted of a three-span Pratt through truss measuring 380 feet in total length with a 20-foot-wide deck. ⁷ It carried a single track of the Mahoning & Shenango Street Railway and included six-foot sidewalks on both sides.

During the early 20th century, Mahoningtown experienced rapid growth, with its population increasing from approximately 5,000 to nearly 10,000 residents. ³ The ward also saw significant industrial development, aided by extensive flat land along the Shenango River.

As early as November 1901, city officials called for the construction of a modern bridge over the Shenango River and adjacent railroad tracks between Mahoningtown and Moravia Street. ⁷ The proposal received court approval in April 1902. By 1905, discussion shifted toward replacing the existing Gardner Avenue viaduct with a more direct, high-level route. ^{3 5} The existing alignment crossed nine railroad tracks that were frequently blocked by train movements. In addition, the Mahoning & Shenango Street Railway sought an alternative route to Mahoningtown, as its Mill Street line was heavily congested with commuters traveling from the Fifth Ward.

Two alternative alignments were proposed. ³ One followed Atlantic Avenue in the Sixth Ward, eliminating “The Narrows,” a hazardous railroad crossing near the Black Bridge that concerned the Pennsylvania Railroad. This route would also provide access to Oakland and Mahoningtown and was favored by the streetcar company. The second alignment followed Smithfield Street and was promoted as the lower-cost option.

Ultimately, planners selected a route centered on Mahoning Avenue, connecting to South Moravia Street at Terrace Avenue on the east side of the river. ⁵ The Pennsylvania Railroad, Buffalo, Rochester & Pittsburgh Railroad, Baltimore & Ohio Railroad, and Erie Railroad agreed to finance construction of the viaduct over their respective tracks, while the county committed to building the river spans and approaches.

Despite these agreements, the proposal stalled due to lack of public interest ⁵ and its estimated cost of $600,000. ⁷ The issue was revived in early March 1908, when the Gardner Avenue Bridge was declared unsafe and closed to traffic. ⁴ The Mahoning & Shenango Street Railway pressed for repairs to restore service.

On March 23, 1913, a series of severe rainstorms inundated western Pennsylvania. ² By March 25, Neshannock Creek and the Shenango River had overtopped their banks, forcing widespread industrial shutdowns. Bridges throughout the region were subjected to extreme stress from rising waters.

In the early hours of March 26, the Black Bridge broke free from its abutments and floated downstream intact, striking a Carnegie Steel Company water intake structure before colliding with the Franklin Railroad Bridge. ² The Franklin Bridge, burdened by eight coal-filled railcars, collapsed later that afternoon. The combined debris continued downstream and struck the Gardner Avenue Bridge, which collapsed at approximately 6:00 p.m. The wreckage eventually lodged against the Buffalo, Rochester & Pittsburgh Railroad Bridge.

Following the disaster, the Gardner Avenue crossing was replaced with a temporary footbridge. ² Estimates placed the cost of a permanent automobile and streetcar replacement at $60,000. ⁷ The footbridge was dismantled in 1925, ⁸ though the center pier remained until its removal on March 17, 1960. ¹¹

Mahoning Avenue Viaduct

Plans for the Mahoning Avenue Viaduct were revived in 1911, when the county requested designs for a shorter crossing. ⁷ The catastrophic flooding of 1913 shifted responsibility to the Commonwealth of Pennsylvania, which committed to reconstructing highway bridges destroyed on navigable streams.

The new bridge was proposed as a reinforced concrete arch structure with a 300-foot clear span over the Shenango River, a 30-foot roadway, and ten-foot sidewalks. ₇ The total estimated cost was $517,800, with the state expected to contribute $60,000. ⁸

On December 12, 1919, representatives of the Pittsburgh & Lake Erie Railroad requested that the eastern terminus be relocated to Jefferson Street on the south bank of Big Run, extending the crossing over Moravia, multiple railroad tracks, and the river. ⁶ The railroad estimated the change would increase construction costs by $200,000.

Funding was finally secured in March 1923, and construction commenced shortly thereafter. ⁸ Designed by John Farris and Thomas A. Gilkey, the 1,195-foot-long viaduct was built by the Independent Bridge Company of Pittsburgh. The structure consisted of three Pennsylvania through-truss spans measuring 307, 306, and 207 feet, along with eight deck plate girder approach spans. The Mahoning Avenue Viaduct was dedicated on December 18, 1924.

In 1940, the bridge deck over the Shenango River was replaced with a reinforced concrete slab. ¹⁰ On May 15, 1957, a portion of the deck on an approach span collapsed, prompting immediate repairs and the imposition of a ten-ton weight limit and a 25 mph speed restriction. A full rehabilitation was ordered, ⁹ estimated at $191,000, but disputes arose over cost sharing due to the bridge’s ownership structure. ¹⁰

Rehabilitation work began in late 1958 ⁸ and included the removal of much of the deck and the replacement of warped girders. ⁹ Investigations revealed that the bridge had suffered from long-term neglect, including inadequate painting. Although bridges were typically repainted every five years, the viaduct had been painted only twice, most recently in 1944. Funding disputes were resolved in the fall of 1960, and repairs by Conn Welding were completed in time for the bridge to reopen on October 7, 1961. ⁸ The viaduct underwent another renovation beginning in April 1986 and reopened on August 30.

A major rehabilitation project undertaken by the Pennsylvania Department of Transportation began on May 16, 2016. ¹² The two-year project included repainting the bridge, replacing bearings, repairing steel and substructure elements, installing LED lighting, and adding new pedestrian railings.

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Gallery

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Details

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Sources

1. “Road and Bridge Views.” New Castle Herald, 12 Mar. 1902, p. 1.
2. “Old Black Bridge – New Castle PA.” Lawrence County Memoirs, article.
3. “What Leading Citizens Think of Proposed Two Routes to Mahoningtown.” New Castle Herald, 21 Mar. 1907, p. 7.
4. “Can Repair Bridge.” New Castle Herald, 12 Mar. 1908, p. 1.
5. “Talk of Viaduct is Again Revived.” New Castle Herald, 27 Mar. 1908, p. 3.
6. “Wants Big Viaduct Changed.” New Castle Herald, 12 Dec. 1919, p. 1.
7. “Mahoning Avenue Viaduct.” The Bureau of Engineering of the Public Service Commission of the Commonwealth of Pennsylvania, Harrisburg, WM Stanley Ray, 1915, pp. 68-71.
8. “Mahoning Avenue Viaduct – Maoningtown (New Castle) PA.” Lawrence County Memoirs, article.
9. Daniels, Don. “Mahoning Viaduct, Tribute to Red Tape.” New Castle News, 27 May 1959, p. 1.
10. “PUC Hearing On Viaduct Is Continued.” New Castle News, 23 May 1958, pp. 1-2.
11. “City Hall Sidelights.” New Castle News, 18 Mar. 1960, p. 18.
12. Wachter, Debbie. “Viaduct heads PennDOT list of local road, bridge projects.” New Castle News, 10 Mar. 2016.