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All the United States Pennsylvania Pittsburgh Nine Mile Run

Nine Mile Run

This picturesque stream was up until recently the site of a ten story mountain of slag and sewage.

Pittsburgh, Pennsylvania

Added By
Thomas Harper
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Nine Mile Run   thomasharper / Atlas Obscura User
Nine Mile Run   thomasharper / Atlas Obscura User
Ducks in Nine Mile Run   thomasharper / Atlas Obscura User
Dumping slag into the valley of the stream.   nmr.collinsandgoto.com
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Nine Mile Run trailhead   blimpcaptain / Atlas Obscura User
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1/17/22   jemoyer1 / Atlas Obscura User
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About

A stream that runs through Pittsburgh city limits, Nine Mile Run is surrounded by trees and wetlands, and fish and ducks make their home in and by the water. But just a few years ago, most of the run was a large slag dump and was choked with sewer runoff.

Pittsburgh's steel industry was the result of nearby geology. Nearby iron and coal seams along with river transport made the area a natural center for steelmaking, starting in the 1850s. For the Allied World War II effort, the mills supplied 95 million tons of steel. In the process of smelting iron ore for all this steel, the waste product left over is called slag, a glassy mixture of metallic oxides and impurities.

Various landfills received slag all over the area, but in 1922 the Duquesne Slag Company bought acreage along Nine Mile Run, built railroad track on the ridge above it, and dumped slag into the valley for 50 years. An estimated 200 million tons were dumped alongside the banks ten stories deep. Pittsburgh's old sewers would also back up and send runoff into the water on rainy days.

Starting in 2006, with the help of the US Army Corps of Engineers and the Nine Mile Run Watershed Association, now known as Upstream Pittsburgh, the restoration of Nine Mile Run began and continues to this day. It is the largest restoration of its kind in an urban area in the country. Fish and ducks can be seen in the water. Wetlands naturally store and filter runoff. Trees in the meadow show vibrant fall foliage. One can walk the Nine Mile Run Trail all the way to where the run, once sodden with waste, meets the Monongahela River.

Related Tags

Environmental Disasters Nature Industrial

Know Before You Go

For the Nine Mile Run Trail, from South Braddock Avenue in the Regent Square neighborhood of Pittsburgh, turn west on Hutchinson Street, then north on Lancaster Avenue and follow the road to the parking lot. Park, then walk past the soccer field to the trail.

Community Contributors

Added By

thomasharper

Edited By

tnmuehlbauer, taylor 970cab79, EricGrundhauser, blimpcaptain...

  • tnmuehlbauer
  • taylor 970cab79
  • EricGrundhauser
  • blimpcaptain
  • jemoyer1

Published

September 29, 2014

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Sources
  • http://ninemilerun.org/about/faqs/
  • http://www.pittsburghparks.org/park-features
  • http://explorepahistory.com/hmarker.php?markerId=1-A-23B
  • http://www.pittsburghquarterly.com/index.php/Region/a-very-brief-history-of-pittsburgh.html
  • http://rob412.blogspot.com/2013/08/crater-trail-in-frick-park.html
  • ninemilerun.org
Nine Mile Run
Nine Mile Run Trail
Pittsburgh, Pennsylvania, 15217
United States
40.426862, -79.90313
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Nearby Places

Bacchus House

Pittsburgh, Pennsylvania

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Pittsburgh, Pennsylvania

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Explore the Destination Guide

Photo of Pittsburgh

Pittsburgh

Pennsylvania

Places 61
Stories 5

Nearby Places

Bacchus House

Pittsburgh, Pennsylvania

miles away

Frick Park Clay Courts

Pittsburgh, Pennsylvania

miles away

Homewood Cemetery

Pittsburgh, Pennsylvania

miles away

Explore the Destination Guide

Photo of Pittsburgh

Pittsburgh

Pennsylvania

Places 61
Stories 5

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