Saw Mill Run is a
tributary
A tributary, or an ''affluent'', is a stream or river that flows into a larger stream (''main stem'' or ''"parent"''), river, or a lake. A tributary does not flow directly into a sea or ocean. Tributaries, and the main stem river into which they ...
of the
Ohio River
The Ohio River () is a river in the United States. It is located at the boundary of the Midwestern and Southern United States, flowing in a southwesterly direction from Pittsburgh, Pennsylvania, to its river mouth, mouth on the Mississippi Riv ...
in
Pennsylvania
Pennsylvania, officially the Commonwealth of Pennsylvania, is a U.S. state, state spanning the Mid-Atlantic (United States), Mid-Atlantic, Northeastern United States, Northeastern, Appalachian, and Great Lakes region, Great Lakes regions o ...
. It is an
urban stream, and lies entirely within
Allegheny County, Pennsylvania
Allegheny County ( ) is a County (United States), county in Pennsylvania, United States. As of the 2020 census, the population was 1,250,578, making it the List of counties in Pennsylvania, state's second-most populous county, after Philadelp ...
. The stream enters the Ohio just downstream from the
Forks of the Ohio in
Pittsburgh
Pittsburgh ( ) is a city in Allegheny County, Pennsylvania, United States, and its county seat. It is the List of municipalities in Pennsylvania#Municipalities, second-most populous city in Pennsylvania (after Philadelphia) and the List of Un ...
, at a place that was founded as the town of
Temperanceville in the 1830s. It provides an entry through the elevated plateau south of Pittsburgh known as the South Hills, and land transportation has paralleled the stream since the nineteenth century.
The stream is named for an actual saw mill that operated near the mouth of the stream where it empties into the
Ohio River
The Ohio River () is a river in the United States. It is located at the boundary of the Midwestern and Southern United States, flowing in a southwesterly direction from Pittsburgh, Pennsylvania, to its river mouth, mouth on the Mississippi Riv ...
. The first reference to the mill is in relation to the construction of
Fort Pitt (1759–1761). The mill provided much of the lumber used in the construction of the new Fort, after the British claimed the area from the French and destroyed
Fort Duquesne.
Railroads
The
Coal Hill Coal Railroad crossed the stream on a trestle, and extended upstream in 1861. This railroad was purchased by the
Pittsburgh and Castle Shannon Railroad, who extended the line to follow the main stream of Saw Mill Run from the
Pittsburgh and Castle Shannon Tunnel to
Castle Shannon, Pennsylvania. The
Little Saw Mill Run Railroad followed the west branch of the stream towards
Mt. Lebanon, Pennsylvania.
The
Wheeling and Lake Erie Railway (W&LE) operated a short rail line on the western end of the stream, known as the West End Branch. It had been used by the
Pittsburgh and West Virginia Railway as a connection with the
Pittsburgh and Lake Erie Railroad near West Carson Street. The W&LE operated it until late 2008, and most of the line has been torn up, with the crossing signal cantilevers on Steuben Street being removed in 2012.
Trolley and light rail
The right of way of the Pittsburgh and Castle Shannon, excluding the Pittsburgh and Castle Shannon Tunnel through a coal mine, was leased by
Pittsburgh Railways
Pittsburgh Railways was one of the predecessors of Pittsburgh Regional Transit. It had 666 PCC streetcar, PCC cars, the third largest fleet in North America (after Toronto Transit Commission, Toronto (745) and Chicago Surface Lines, Chicago (683) ...
in 1905, and later purchased in 1950. The railroad ran with a dual gauge system, with coal trains continuing to run on the narrow gauge, and at night, and trolleys on a wider gauge. The right of way is part of the
Pittsburgh Light Rail transportation system today, which follows the stream from near the
South Hills Junction (PAT station) to Castle Shannon, Pennsylvania.
Highways
Part of
Pennsylvania Route 51 runs parallel to the stream, and this section is known as Saw Mill Run Boulevard.
Watershed
The watershed of Saw Mill Run covers , or about . The main stream is long, and drains parts of Bethel Park, Castle Shannon, Mount Oliver, and the city of Pittsburgh.
[ ]
See also
*
List of rivers of Pennsylvania
This is a list of streams and rivers in the U.S. state of Pennsylvania.
By drainage basin
This list is arranged by drainage basin, with respective tributaries indented under each larger stream's name.
Delaware Bay
Chesapeake Bay
*''E ...
References
{{authority control
Pittsburgh metropolitan area
Rivers of Pennsylvania
Tributaries of the Ohio River
Rivers of Allegheny County, Pennsylvania