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West Creek is a small tributary within the
Schuylkill River watershed. This
ephemeral stream passes over abandoned
subsurface coal mines. During periods
of low rainfall, the stream is known to lose
all its flow to the subsurface mine pool. This
location was first surveyed with geophysical
methods in 2012 in the
West West Branch
Hydrogeology and Geophysics project.
Resistivity profiles were used to pinpoint
locations of potential streamflow loss along
this reach of stream channel.
Follow-up investigations were performed in
2013 through streambed temperature
measurements and geochemical analysis of
water samples in collaboration with Dr.
Chuck Cravotta, a
geochemist with the
United States
Geological Survey stationed in
Harrisburg, and
Dr. Lauren Levine (KU
Chemistry).
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West Creek of the Schuylkill River watershed
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Dea
Musa constructs the temperature probes for
streamed temperature measurements.
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Vertical temperature probes were constructed
to measure the stream channel temperature
profile over the course of two months.
Thermocron iButtons, model #DS1922L,
were used to record the temperature
measurements. Four temperature sensors
were installed in cavities drilled into each
probe. The cavities were filled with
silicone and the sensors were inserted into
the silicone to create a waterproof seal.
The first sensor was installed on a level
with the streambed. The three
subsurface sensors were installed at depths
of 0.03m, 0.06m and 0.10m. Temperature
measurements were made every 20 minutes for
a period of 2 months between May 2013 and
July 2013.
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Water quality measurements were initially
made using a YSI 556 multiparameter water
quality meter to provide temperature, pH,
specific conductance, dissolved oxygen, and
redox potential data. To further
investigate the variation of water quality
along the stream channel, water samples were
taken to produce a more detailed chemical
analysis of the water. Concentrations
of major anions (SO4 and Cl) were
analyzed by ion chromatography and
concentrations of major cations,
particularly the trace metal Iron (Fe) were
analyzed by atomic absorption spectrometry.
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Dr. Cravotta and
Leanne Hillegas and collect water samples in
West Creek |