Saw Mill Run Boulevard - State Route 51
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Saw Mill Run Boulevard runs along the Saw Mill Run Corridor, following the path of Saw Mill Run Creek. It begins at the intersection of Clairton Road and Stewart Avenue on the City of Pittsburgh boundary with Brentwood.
The roadway runs north through Overbrook and forms the eastern border of Brookline. It passes the Liberty Tunnel/West Liberty Avenue and the Fort Pitt Tunnel/Parkway West interchanges. It ends at the West End Circle near the entrance to the West End Bridge.
A four-lane road its entire length, the northernmost section, known as the West End Bypass, is designated an expressway. The Bypass runs from the Parkway West interchange to the West End Circle. The entire roadway is part of State Route 51 and US Route 19.
Saw Mill Run At The Turn-Of-The-Century
In the early 1900s Saw Mill Run was no more than a dirt path leading south along Saw Mill Run Creek from the intersection of West Liberty Avenue and Warrington Avenue. The township road, called the Warrington Avenue extension or Kaiser Avenue, ran to a point near Edgebrook Avenue. When World War I began, the name Kaiser Avenue was replaced with Saw Mill Run Road
At Edgebrook Avenue began a patchwork of residential streets in the old town of Reflectorville. After passing through the village to Nobles Lane, the Library Road Extension carried travelers through to the town of Fairhaven and the Library Road intersection.
Rapid Development Of The South Hills
As development of Pittsburgh's southern neighborhoods and nearby suburbs began in earnest, the need for a better roadway became a necessity. With the construction of the Liberty Tunnels underway in 1920, the transformation of the Saw Mill Run Valley began.
The project would take another twelve years to complete, but by 1932 there would be a four-lane highway stretching from the Stewart Avenue in Overbrook all the way to the Banksville Traffic Circle. Further road construction in the 1950s took the boulevard from the Traffic Circle to the West End and West Carson Street. The purpose of this photo narrative is to describe that process in detail.
Preparations For A Modern Roadway Begin In 1925
In anticipation of the construction of a major roadway through the Saw Mill Run Valley, and the urgencies created by the rapid residential and commercial development of the nearby area, construction of a forty-two inch sewer line from the West Liberty Avenue extension to Bausman Street and along the Saw Mill Run Valley to Warrington Avenue began in June 1925. The modern sewer line and other infrastructure improvements laid the groundwork for future construction.
"City Beautiful" Bond Issue - 1928
Saw Mill Run Boulevard was created as 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. After the completion of the Liberty Tunnels in 1924, the city of Pittsburgh became easily accessible to the South Hills area.
As the southern communities grew, county and city planners looked for a roadway that would connect eight important throughway and improved roads (Library Road, Nobles Lane, West Liberty Avenue, Banksville Road, Washington Pike, Noblestown Road, Steubenville Pike and Carson Street.) It was also viewed as a way to bring the cities of McKeesport, Clairton and Duquesne closer to Pittsburgh.
Construction - The Library Road Extension - 1929/1930
Construction began quickly. The first phase of construction would be the section that ran from the Library Road Extension to Reflectorville, then on towards through Warrington Avenue extension that ran past the Liberty Tunnels to Warrington Avenue proper in Beltzhoover. Many engineering challenges laid along the chosen path.
One major engineering design challenge was the intersection at Library Road (Route 88). This heavily traveled interchange lay in the heart of Overbrook Borough, seven individual roads all converged on one location. In addition to the roads, there was the confluence of the Clairton Run Creek and the Saw Mill Run Creek, through both of which flowed a substantion amount of water.
Library Road, Ivyglen Street, Hillview Avenue, Stewart Avenue, and Glenbury Street all had to be merged with Saw Mill Run Boulevard. The resulting interchange consisted of a concealed system of five bridges with tunnels to channel the water.
Another engineering difficult was overcoming the multiple road network near the Whited Street (Oak Street) intersection. This would require a complete reconfiguration and reconstruction, as there was no single intersection or actual through road at this point, just a merging of several different streets.
Engineers designed the layout of the boulevard to follow the existing Library Road Extension from Route 88 to Whited Street, then follow Second Avenue through Reflectorville (Overbrook) to near Edgebrook Avenue. The roadway would then veer towards Ensign Avenue and proceed for a short distance. From there a path was cut until the boulevard merged with the existing Warrington Avenue extension.
After nearly a year of hard work, the first phase in the construction of Saw Mill Run Boulevard was completed on December 1, 1929. To the delight of many residents of Overbrook, Carrick, Whitehall and Brookline, the new highway was a significant improvement for motorists and helped spur further development in their districts, both residential and commercial.
Prior to the grand opening, City Planners considered changing the name of the roadway from Saw Mill Run Boulevard to Liberty Boulevard, but this proposal never gained momentum. So, in the Spring of 1930 a special dedication and parade was held signaling the official opening of Saw Mill Run Boulevard.
Construction - Warrington To Woodruff - 1930
During the next phase of construction, the boulevard was extended from Warrington Avenue to Woodruff Street. Some of the necessary infrastructure work had been going on for months during the First Phase of construction and, in the case of the sewer line, since 1925. This enabled the Second Phase of construction to be completed in the late-Summer of 1930.
With the exception of a dirt pathway from Warrington Avenue to Crane Avenue, this was all new roadway. The major challenges were creating a cut through the rocky hillside between Crane Avenue and Woodruff Street, and the construction of a new portal bridge over which ran the freight trains of the Wabash Terminal Railway from it's hub in downtown Pittsburgh. This second stretch of roadway opened on September 9, 1930.
From its' terminus at Woodruff Street, inbound motorists either turned right and headed up narrow Woodruff and over Mount Washington to McArdle Roadway, or they turned right and followed the paved Pittsburgh Railways streetcar line to Woodville Avenue and on towards the West End and West Carson Street. With the pending improvements to Banksville Road and other transportation initiatives looming in the near future, these were a short-lived alternatives.
* Thanks to Tim Killmeyer for many of the Phase One and Phase Two images *
The Banksville Traffic Circle - 1932
With the rapid development of the South Hills area, it was apparent from the start of the Saw Mill Run project that it was necessary for the boulevard to connect with Banksville Road and Woodville Avenue. This would facilitate traffic to the West End and fit in with some long range plans that had been sitting idle for several years.
This led to the creation of the Banksville Traffic Circle, a large looping turn-around at the end of Banksville Road that connected with Saw Mill Run Boulevard and Woodville Avenue. Construction of the circle was completed in 1932 and it provided some relief with the traffic flow on the southern side of Mount Washington.
Another improvement that followed was the Woodruff and Merrimac Street Improvement project in 1934. Both Woodruff and Merrimac were widened to four lanes to help provide another reliable route for the ever-increasing amount of vehicular traffic from the South Hills to downtown Pittsburgh.
Improvement Plans - What Might Have Been - 1934
The next step in the improvement of the South Hills transportation network was something that had been in the minds of planners since the 1910s, when planning for the Liberty Tunnels was underway. These plans included the improvement of Banksville Road to a four-lane boulevard and the construction of another South Hills tunnel and bridge to downtown.
The Fort Duquesne Tunnels and Bridge was under serious consideration in 1934. The $8,000,000 project would start at the Banksville Traffic Circle and include Twin Tubes, 3,750 feet in length, and a bridge over the Monongahela River that connected to Water Street, Liberty Avenue and the existing Point and Manchester Bridges.
Funding for these two projects, along with the Woodruff Street improvement, were to come from a mixture of federal Works Project Administration dollars and imposing tolls on motorists passing through both the Liberty Tunnels and, when complete, the Fort Duquesne Tunnels. After much debate, these plans were eventually scrapped. Woodruff Street and Banksville Road were improved with federal funding, but the tunnel and bridge project were shelved.
Construction - The West End Bypass - 1949/1951
The reconstruction of Banksville Road in 1938 was the last in the long series of South Hills traffic improvements for ten years. During this time, the City of Pittsburgh hired famed planner Robert Moses to design a far reaching transportation initiative that would solve Pittsburgh's traffic nightmares for years to come.
In 1939, he submitted the extensive "Moses Plan", which, if implemented in it's entirety, would finally bring Pittsburgh into sync with the ever-expanding age of the automobile. In the South Hills area. this plan included construction of the Saw Mill Run Extension, better known as the West End Bypass, the Parkway West and the Fort Pitt Tunnels and Bridge.
Construction of the West End Bypass began in October 1949. The modern four-lane expressway, a little over a mile in length, would extend along the Mount Washington hillside from the Banksville Traffic Circle to West Carson Street. The biggest engineering challenge was the extensive excavation of the hillside to accomodate the roadway.
It took over a year of blasting to remove the one million cubic yards of rubble needed to accomplish the task. Trucks carried away the mountains of soil, 5000 cubic yards a day, in convoys to locations along Greentree Road and near Langley High School to make land for athletic fields.
Another challenge for the contractor, Harrison Construction Company, was the creation of a long ramp from Steuben Street to link outbound motorists with the new expressway. When the project was completed in the Spring of 1951, South Hills motorists could now zoom from the Traffic Circle to Carson Street without having to pass through the West End Business District. What once took up to one half hour or more now was a matter of a few minutes or less.
Construction - The Fort Pitt Tunnel Interchange - 1952/1957
The final piece of the Saw Mill Run Boulevard construction project occured between 1952 and 1957. This entailed the removal of the Banksville Traffic Circle and replacing it with a modern interchange that would connect Saw Mill Run Boulevard, the West End Bypass, Banksville Road and Woodville Avenue with the soon-to-be-constructed Fort Pitt Tunnels, Fort Pitt Bridge and Parkway West (I279).
Aside from the challenge of building the multi-ramp interchange, engineers faced with another extensive hillside excavation in order to make the necessary room for the tunnel entrance and the interchange. The West End Bypass began a three-month closure in May 1952 and the task of removing the mountain of rock began.
Aside from the excavation of 710,000 cubic yards of earth and rock from the 259-foot hillside, the $4.5 million project required relocation of two railroad bridge and the replacing of sewage facilities. Then, of course the construction of the highway, tunnels and accompanying bridge over the Monongahela River, which was following the same general path of the Fort Duquesne plan from 1934.
The fill from the hillside went to fill the valley for the section of the Parkway West known as Greentree Hill. The Traffic Circle was removed and a temporary restricted roadway was built to link Saw Mill Run with the West End Bypass. The remainder of the interchange project took five more years to complete. By 1957 Saw Mill Run Boulevard was complete.
It was a further three years before the Parkway West, Fort Pitt Tunnels and Fort Pitt Bridge were all linked together with Saw Mill Run Boulevard. Never-the-less, the twenty-eight year Saw Mill Run Boulevard and West End Expressway projects were instrumental components in modernizing the road network of the South Hills to meet the transportation needs of the future. Their completion meant that, transportation-wise, Pittsburgh had truly entered the twentieth century.
Liberty Tunnels South Interchange - 1998/1999
After sixty years of service, Saw Mill Run Boulevard began to see improvements made during the 1990s and 2000s. In the early 1990s median barriers were installed from Whited Street north to the Parkway West interchange. In 1998 work began on a new traffic design where Saw Mill Run meets West Liberty Avenue and the Liberty Tunnels.
The heavily-traveled interchange, which handles over 100,000 vehicles per day, had been a bottleneck for years. Plans were in place in 1957 for a design change, but they were never put into action. Finally, in 1999, the new interchange was completed and has been hailed as a major improvement by almost everyone who lives in the South Hills.
The West End Circle Interchange - 2005/2010
Construction of a new traffic design pattern at the equally-crowded Northern Terminus of Saw Mill Run Boulevard, approaching Carson Street and the West End Bridge, began in the mid-2000s. An additional lane was added to the highway and the hillside was stabilized.
The intersection at the West End Circle was redesigned, with the construction of a third tunnel to allow a more coordinated traffic flow. The project was completed in 2010. The new interchange was welcomed by motorists as another major improvement.
The Route51/Route 88 Interchange - 2013/2015
The next improvement was made at the southern edge of the Boulevard, where a complete rehabilitation of the overcrowded Library Road (State Route 88) intersection took place from 2013 through the fall of 2015. The heavily traveled interchange had become a serious chokepoint for traffic and a dangerous safety concern.
In the works since the late 1990s, initial improvement plans favored a design similar to the interchange at the Liberty Tunnels. However, after over a decade of deliberation and delays, new plans were introduced in October of 2010, approving a jughandle design.
Construction of the new interchange began in late-2013. Over the next several months, severan decaying bridges along the construction path were rebuilt. Utilities and traffic signals were improved. The roadway was completely rebuilt. At a cost of over $20 million, the construction project was completed in November 2015. South Hills motorists cheered the new interchange, which dramatically improved the flow of traffic at this major intersection.
Further Improvements - 2017/present
Finally, in 2017, PennDot contracted Gulisek Construction to perform a $4.32 million improvement project on the Liberty Tunnels South Interchange. The project ran from March to July, and included concrete patching, an asphalt overlay, bridge preservation, drainage improvements, ADA curb cut ramp installation, signage and signal upgrades, ramp reconstruction, and other miscellaneous construction activities.
Photos of Locations Along Saw Mill Run Boulevard
For More Pictures Of
Saw Mill Run Boulevard
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