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Roman G. Kyshakevych, Ph.D.
Henry S. Prellwitz, Ph.D.
The intent of the 3r2n Green Infrastructure
study is to describe and document conditions of riverbank geology,
accessibility, preservation, and restoration potential along the
Monongahela and Youghiogheny Rivers in Pools 2 and 3, Allegheny
County, Pennsylvania. Data collected during the 2001 field season
includes bank and berm slopes, heights, material types and grain
sizes, material conditions, accessibility potential, and floodplain
identification. Data was collected along 1/10th mile sections
of each bank, which were identified in the field with a Global
Positioning Receiver (GPS). This data was entered into a database
for later GIS and ARCINFO analysis. Riverbank access was graded
into three categories, and mapped with ARCVUE computer software.
Preservation data was also graded into three categories, and mapped.
The data from the access and preservation maps was filtered through
a Boolean truth chart, and riverbank sections worthy of restoration
were identified, graded, and mapped. Riverbank grain sizes and
material distribution were plotted for each pool, and the resulting
trends discussed.
- Three different cases of riverbank access
were generated-no access, moderate access, and easy access-by
looking at the slope and composition of both of the bank and
the berm.
- Three different grades of riverbank preservation
were created,-best preservation, moderate preservation, poor
preservation.
- The restoration potential is contingent
on bank height (and potential floodplain affect) as well as
soil composition.
Overview of Riverbank materials both natural
an manmade:
- Man-made bank materials in the four major
rivers are predominated by rubble/fill, which was used for railroad
right-of-way construction.
- The average ratio for the riverbanks of
the Monongahela, Allegheny, and Ohio Rivers is about 27% natural
material, and 73% man-made.
- The Monongahela River has a much higher
percentage of slag in the riverbanks, compared to the other
three rivers due to the steelmaking that was the major industry
in the Monongahela Valley.
- Natural material concentrations for the
Monongahela River banks increase upstream, due to less impact
from past heavy industrial activity
- The Youghiogheny has a very high percentage
of rubble/fill,from railroad construction.
- The Youghiogheny has 65% natural material,
and 35% man-made bank material; this trend is due to the relatively
light industrialization and poor navigability compared to the
three major rivers.
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