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MATERIALS
AND METHODS
Thermal
Monitoring:
Stream
Temperature
In
1992, thermal monitoring stations were established at 4 Kinnickinnic
River locations throughout River Falls:
Quarry
Road (Upper City Limits) (Middle River)
Cedar
Street (Commercial and Residential Area) (Middle River)
Upper
Glen Park (Downstream from 2 City Impoundments) (Lower River)
Lower
Glen Park (Lower City Limits) (Lower River)
The
Kiap-TU-Wish Chapter of Trout Unlimited purchased and installed
the stream temperature monitoring equipment.
The
temperature monitors are Ryan TempMentor datalogging thermometers,
manufactured by Ryan Instruments, Redmond, WA (Figure 1). The instrument
allows storage of 6400 temperature measurements in a range from
-32 C to +70 C (0.1 C resolution; 0.3 C accuracy). The thermistor
temperature sensor is mounted on a cable that attaches to the TempMentor,
allowing the sensor to be located up to 100 feet away from the thermometer.
The
TempMentor has variable temperature-logging intervals ranging from
1 second to two hours. A 10-minute logging interval is used for
Kinnickinnic River studies, allowing a 44-day deployment time. The
10-minute logging interval provides good sensitivity for detecting
rapidly-rising stream temperatures during storm events.
TempMentor
deployment and data retrieval are conducted in the field, with a
lap-top IBM-compatible PC (Figure 1). The accompanying software
creates a data report and thermograph for each data set.
Each
TempMentor is housed in an in-ground, locking shelter, to ensure
security. The sensor cable extends through an underground plastic
conduit, to the streambed (Figure 1).
The
Monitor's "Bunker"
The
Site When Camouflaged
Stormwater
Temperature
From
June-August, 1992, a single TempMentor was deployed in a storm sewer
draining a highly impervious, 13-acre commercial area in downtown
River Falls. The TempMentor was housed in a modified milk can suspended
from the grate at the top of the access hole. The sensor cable extended
from the milk can through a plastic conduit to the bottom of the
concrete storm sewer, at a location 20 feet from the discharge point
to the Kinnickinnic River.
A
10-minute temperature logging interval was employed. During dry
periods, the TempMentor logged cool, ambient air temperatures within
the storm sewer. During rain events, the TempMentor logged stormwater
temperatures, which were markedly higher than the air temperatures,
allowing a clear delineation of the onset and duration of the rain
event, in addition to stormwater temperatures throughout the event.
Stormwater
Quality Monitoring:
From
June-August, 1992, Short Elliott Hendrickson (SEH) conducted automated
event-based monitoring of stormwater quality in River Falls. Stormwater
from representative subwatersheds of three urban areas was sampled:
residential (29 acres), commercial (13 acres), and industrial (80
acres).
An
American Sigma 800 SL portable sampler was used for sample collection.
Stormwater flow rate was monitored continuously by the sampler's
integral flow meter. Flow depth information was obtained with a
pressure transducer mounted on the bottom of the storm sewer.
For
each storm event, discrete samples were collected, with more frequent
sampling at the beginning of the event to better characterize first
flush. All discrete samples were flow-composited prior to analysis.
Storm
event selection for monitoring followed the EPA NPDES stormwater
monitoring requirements to the greatest extent practicable. Samples
were collected during measurable storm events (greater than 0.1
inch) occurring at least 72 hours from the previously measurable
storm event. The rainfall characteristics used for event selection
have been summarized by SEH (1995).
Three
acceptable storm events were monitored in the residential and commercial
subwatersheds, while a single storm event was monitored in the industrial
subwatershed.
Each
flow-composited stormwater sample was analyzed for the following
water quality variables: total suspended solids, total Kjeldahl
nitrogen, total phosphorus, copper, lead, and zinc. For the suite
of water quality variables analyzed, 1992 stormwater quality results
for River Falls were compared with EPA (1983) National Urban Runoff
Program (NURP) results.
Kinnickinnic
River Water Management Plan:
Recognizing
that protection of Kinnickinnic River water quality is critical
to the environmental and economic future of River Falls, and that
development along the Kinnickinnic River needs to be carefully planned
to protect the existing resource, the City of River Falls applied
for and received a federal EPA 205J water quality planning grant
in 1991.
The
EPA 205J grant ($94,000), administered by the Wisconsin Department
of Natural Resources (WDNR), was supplemented by funding from the
City of River Falls ($16,900) and the Kiap-TU-Wish Chapter of Trout
Unlimited (TU) ($4,200). In-kind contributions of staff were provided
by the four local townships, the Kinnickinnic River Land Trust (KRLT),
and the University of Wisconsin-River Falls (UW-RF), as well as
WDNR, the City of River Falls, and TU.
Short
Elliott Hendrickson (SEH) of St. Paul, MN, a water resource consultant,
was selected to develop the Kinnickinnic River Water Management
Plan, in partnership with the WDNR, City of River Falls, townships,
TU, KRLT, and UW-RF. The total cost of the three-year (1992-1994)
planning effort was $115,100, not including the in-kind staff contributions
of all partners except SEH.
WDNR
Priority Watershed Program:
In
1995, the Kinnickinnic River was selected by the WDNR for inclusion
in the state priority watershed program. This program will provide
annual funding over a ten-year period for implementation of both
urban and agricultural BMPs throughout the Kinnickinnic River watershed,
potentially including some of the suggested BMPs in the City of
River Falls' Kinnickinnic River Water Management Plan.
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