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Introduction
Kathy Knauer, Environmental Scientist
This water quality study is a strategic program
developed by the STUDIO for Creative Inquiry, in partnership with
3 Rivers Wet Weather Inc. (3RWW), ALCOSAN, and the Allegheny County
Health Department (ACHD). It is intended to reveal patterns and
relationships between water quality, public use and the functioning
ecosystems of our urban river systems. The project provides a
relatively short-term, low-budget, strategic survey of water quality
over a broad geographic area. The project began in 2000 in the
Pittsburgh Pool. In 2001, Year 2, the project focused on the upper
Monongahela River from Locks and Dam #2 at Mile Point 11.3 near
Braddock, PA to the Allegheny County line at Mile Point 35
Dry Weather: Our sampling indicates that dry
weather water quality conditions are quite good. They meet our
target water quality standard for recreational use most of the
time. In the 2001 recreational season (May 15 - September 30),
70 of 138 days when it was considered safe for direct contact
with river water by Allegheny County Health Department River Water
Advisories. According to the advisories, it was considered safe
to use our rivers for direct body contact 51% of the time from
May to September 30, 2000.
Wet Weather: Our data suggest that in Pool
3, Mile Point 35 to 27.8, little lasting impact on fecal coliform
concentrations is seen with storms less than 0.70 inches. Higher
fecal coliform concentrations were seen for a wet weather event
with 1.2" of rain. Pool 2 data from Mile Point 16.7 and 14.3 indicated
a larger impact on fecal coliform concentrations for the 3 wet
weather events sampled compared to Pool 3. Pittsburgh Pool data
shows higher concentrations and apparent duration during the same
sampling events than the upper pools.
Tributary Streams: Our study shows that during
dry weather, fecal coliform vary among the tributary streams studied.
While several streams had fecal coliform concentrations under
200 CFU/100ml, three streams had samples greater than 105 CFU/100ml.
Chemical and field tests indicate most parameters within an expected
range for this region and within state water quality standards.
However, many of these tributary streams flow through municipal
parks or neighborhoods.
While the problem of fecal contamination problem
is present in many the tributary streams, the ecological potential
of these streams cannot be overlooked.
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