A look at Pittsburgh's Saw Mill Run Boulevard

Saw Mill Run Boulevard - Pennsylvania State Route 51 - runs through the narrow Saw Mill Run Valley.  It begins at the intersection of Clairton Road and Provost Road at the City of Pittsburgh Line with Brentwood.  It ends at the West End Circle at the entrance to the West End Bridge.  A four-lane highway for its entire length, Saw Mill Run Boulevard consists of interchanges at the South Portal of the Liberty Tubes and with the Parkway West.  It is an expressway from the Parkway to the West End Circle (West End Bypass).  One of the most well-known traffic tie-ups in the Pittsburgh area occurs between Maytide Street and PA 88 (Library Road) which is simply known as 'Maytide and 88.'

History:
Saw Mill Run Boulevard was part of the 1928 Allegheny County 'City Beautiful' bond issue.  The bonds resulted in the creation of Saw Mill Run, Ohio River, Allegheny River, and Mosside Boulevards. (1)   After the completion of the Liberty Tunnels in 1924, Downtown Pittsburgh was officially accessible from the South Hills.   As a result of the new tunnels linking downtown to the South Hills, communities like Dormont, Mt. Lebanon, Brookline, and Overbrook grew.  Because of this growth, county and city planners looked for a roadway that would "...tie together...eight important throughway and improved roads, (Library Road, Nobles Lane, West Liberty Blvd. or Old Washington Road [now W. Liberty Ave.], Banksville Road, Washington Pike, Noblestown Road, Steubenville Road and Carson Street.)" (2)   The new highway was also considered as a way to bring the cities of McKeesport, Clairton, and Duquesne closer to Pittsburgh.  Construction began quickly and half of the roadway, from Library Road (PA 88) to near Knoxville, opened on December 1, 1929. (3)  The roadway from Banksville Road to Knoxville opened in 1930.  Shortly after the boulevard was open completely, local officials wanted to rename it 'Liberty Boulevard.' (4)  This of course did not come to be.

As a result of the new four-lane highway's opening, Pittsburgh's South Hills continued to grow. Sleepy Pittsburgh neighborhoods, such as Overbrook, were quickly filled with businesses and traffic along the highway.  Saw Mill Run Boulevard and as Route 51 continued further south was the gateway into Pittsburgh for the South Hills and many Mon Valley industrial towns.  One of Pittsburgh's most beloved restaurants first opened along Saw Mill Run Boulevard.  Eat 'n Park's first location opened at 2209 Saw Mill Run Boulevard in 1949.
 

Banksville Circle and West-End Bypass Under Construction.
(Clyde Hare)

As Pittsburgh's traffic grew, pressure on the Liberty Tunnels continued to mount.  An extension of Saw Mill Run Boulevard to the Ohio River and the West End Bridge was built.  Originally proposed by the famed planner, Robert Moses, construction on the Saw Mill Run Extension - better known as the West End Bypass - began in 1949.  The 1.1-mile expressway began at Banksville Circle and ran to the West End Bridge. (5)  The extension opened in 1951.  The bypass would see an additional northbound lane built in the mid-1990s to accommodate expected increases in traffic during the Ft Pitt Tunnels & Bridge rehabilitation.
 
The Banksville Traffic Circle was eliminated during the construction of the Parkway West in the late 1950s.  The circle was replaced with an interchange between Saw Mill Run Boulevard and the new highway.  Later improvements in the 1990s and 2000s to Saw Mill Run Boulevard included: median barriers from Whited Street to the Parkway; a complete redesign of the Northern terminus of the Boulevard at the West End was completed in 2010; a jughandle turning lane southbound at Woodruff Street and the opening of the Wabash HOV Tunnel in 2004; and a complete rehabilitation of the Library Road (PA 88) intersection that opened in 2016. 

The reconfigured PA 51 and PA 88 intersection. (PENNDOT)

Liberty Tunnel South Portal Interchange and Saw Mill Run Expressway Plans:
Even during the original construction of Saw Mill Run Boulevard, planners designed a complex interchange with the Boulevard, West Liberty Avenue, and the South Portal of the Liberty Tunnels.  Nothing was done and again in the 1950s, the state offered up plans for an interchange and a Saw Mill Run Bypass of the bottleneck at the tubes.  The interchange was also to be part of a Saw Mill Run Expressway that would widen the highway to six lanes, have controlled or limited access to side streets, and include various interchanges and connections to other proposed freeways.  By this time, Saw Mill Run Boulevard was known more for its traffic headaches than its accessibility to the South Hills.  From the mid-1950s through the mid-1970s, plans were introduced, changed, opposition and support were voiced, and in the end, nothing was done. 

1957 Liberty Tunnel South Portal Interchange Plans.
(Brookline Connection)

It wasn't until the mid-1990s, and the "impending doom" of the closed Fort Pitt Bridge and Tunnels, that talk of an interchange at the South Portal resurfaced.  This time work for a South Portal interchange actually began and was completed.  In 1999, an interchange, a modified single-point diamond, opened to traffic.  Through traffic on Saw Mill Run Boulevard now rode over the intersection that once backed up traffic, sometimes for over a mile.  The new interchange has been received warmly by commuters who no longer have to sit at the ancient traffic lights.
 
Other Proposals:
In the 1930s, Allegheny County attempted to purchase the Wabash Bridge and Tunnel as a way to alleviate traffic with the Liberty Bridge and Tubes.  The move, attempted three times in the decade and spearheaded at times by Downtown Pittsburgh businessmen, failed on each attempt.  One proposal, made in 1936, included an elevated traffic circle interchange that would involve: Saw Mill Run Boulevard, the Wabash Tunnel Highway, and Woodruff Street.  After a 1970s transit proposal known as Skybus went for naught, City of Pittsburgh planners in 1986 considered converting the tunnel to a reversible one-way highway that would connect Saw Mill Run Blvd. to a parking facility at Station Square. (6)  It wasn't again until the 1990s with the fast-approaching Fort Pitt Bridge and Tunnel rehabilitation looming that plans began to materialize to covert the tunnel to a legitimate link from Saw Mill Run into town.  However, it wasn't until December 27, 2004, that the tunnel opened to traffic.  The tunnel sits less than 1000' above the intersection of Saw Mill Run Blvd. and Woodruff Street.
 
Commentary:
After being overlooked for decades, improvements are being made along the Saw Mill Run Corridor.  New interchanges at the Liberty Tubes and West End Bridge, a center median reducing crossover crashes, and improved intersections at Library Road and Woodruff Street are some of the current or completed projects in the area.  Although not the expressway dreamed of in the 60s, transit options such as a total rebuild of the century-old Overbrook Trolley Line, which reopened in 2004, and the 40-year-old South Busway have eased some traffic woes.
 
However, Saw Mill Run Boulevard is still a very tight, traffic-heavy, and dangerous road.  A completed Saw Mill Run Expressway would have greatly improved traffic in the corridor.  In Charlotte, North Carolina, the Independence (Boulevard) Freeway is a great look at what the Saw Mill Run Expressway could have been.  Part limited access and allowing some business and local road access, the Independence Freeway is a great improvement to residents east of the city.  The six and sometimes eight-lane highway, includes an independent bus lane, interchanges with major roads, and a center median.  The freeway is now being extended another mile and a half and will include a major interchange at Albemarle Road, a similar traffic situation to Maytide and 88.

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Sources & Links:

(1) Bruce Cridlebaugh

(2) Stevenson, William H. "Saw Mill Run Valley Improvements." unknown. May XX, 192x.

(3) M'Swigan, Marie. "Mountain of Earth Removed in Course of West End Project." The Pittsburgh Press. October 11, 1929.

(4) "Saw Mill Run Meant Something to Washington." Editorial. Pittsburgh Sun-Telegraph. August 15, 1930.

(5) "Dirt Flying, Trucks Rolling for Saw Mill Run Extension." The Pittsburgh Press. November 27, 1949.

(6) Fisher, Ken.  "Old Wabash Tunnel may be unsealed." Pittsburgh Post-Gazette. May 31, 1986.

Saw Mill Run Boulevard - State Route 51 ---Brookline Connection

PA 51 @ PAHighways.com ---Jeff Kitsko

Saw Mill Run Expressway @ Pittsburgh Highways ---Jeff Kitsko

South Hills Expressway @ Pittsburgh Highways ---Jeff Kitsko