Monitoring the Plaster Creek Watershed
Dean Pettinga, Jenna Kennedy, Darren Proppe PhD, Dave Warners PhD, Calvin College
The Plaster Creek Watershed
The waters of Plaster Creek flow from Dutton and Caledonia
northward, into the City of Grand Rapids. The creek reaches its
confluence with the Grand River on the south side of the city.
Land use types of the watershed include: agricultural, industrial,
and residential (urban and suburban). Plaster Creek is one of the
most polluted waterways in Michigan. In 2001 and 2005 the
Michigan Dept. of Environmental Quality deemed the creek unfit
for partial body contact due to dangerously high levels of E. coli.
The watershed also struggles with storm-water retention, facing
huge storm surges, especially due to the urban and suburban land
use of the region.
Associated Problems
•  The poor quality of Plaster Creek affects everything
downstream: the Grand River, the Great Lakes, the St. Lawrence
seaway, and the Atlantic ocean.
•  Pollution of one of these sources affects all those downstream.
•  Further, the pollution of these waters becomes a detriment to all
our downstream neighbors of the Plaster Creek Watershed.
•  Degradation of these waters proves detrimental to all as they
serve as valuable resources for recreation, commerce, and
natural beauty.
Objectives
319 Grant
•  Plaster Creek Stewards received a grant from the Michigan
Department of Environmental Quality to improve the storm
water retention of watershed.
•  This grant provides funding for the installation of bio-swales in
four areas of concern for storm-water discharge in the Plaster
Creek watershed.
•  Discharge measurements were required for each location in
order to quantify the current discharge and compare it to
discharge data gathered after bio-swale installation.
Coliform Sampling
•  In preparation for another possible grant
for the Plaster Creek Stewards, a pilot
study was performed.
•  The goal was to collect and analyze
water samples along the creek and
Figure 1. Image of Coliscan EasyGel.
several of its various tributaries.
General coliform species appear as
•  These samples were used to identify
blue dots, while E. coli colonies
appear purple.
regions of the watershed contributing
the heaviest levels of E. coli to the creek.
•  Once these high-risk tributaries are identified, their subwatersheds will be assessed for geographical factors such as
land use to determine best management practices for the regions.
Methods
Results
Discharge Monitoring
•  Long-term, baseline discharge data required to assess drainage.
•  Four designated sites: Shadyside Park, Mel Trotter Ministries,
Kreiser Pond, and Calvin College.
•  Proposed bio-swales will
effectively re-route drainage.
•  Solinst Model 3001 Levelogger®
Edge flow transducers were
installed at each site.
•  Devices collect data
once every thirty minutes.
Figure 2. Installation of flow transducer at the
•  Data collection continues after
Calvin College site. Solinst Levelogger ®
bio-swale introduction.
rests in the bottom angle of the tube,
measuring the flow rate of storm-water from a
•  Current data collection
nearby parking lot.
continues until bio-swale
installation begins in 2014. At this point, analysis of preinstallation data may begin.
•  Monitoring with Levelogger® devices will continue throughout
2014, after installation of bio-swales has been completed.
•  Post-installation analysis will be compared to pre-installation
data to assess the project’s efficacy.
Coliform Sampling
•  Samples of E. coli were taken on three separate dates from July
to August.
•  Nine tributaries chosen to monitor regions loading the most E.
coli into Plaster Creek.
•  Suburban
•  Healthy Ravine / Suburban
•  Commercial
•  Industrial
•  Agricultural
Figure 3. A map of the Plaster Creek Watershed with the nine assigned tributaries for E. coli
sampling labeled according to the corresponding land use of their sub-watersheds.
•  Samples were taken from both the creek and tributary at each
site.
•  These samples were plated in Coliscan EasyGel.
•  Data was converted to colony-forming units per 100mL of creek
water.
Coliform Sampling
From initial levels of coliform bacteria observed in the southern
portion of the watershed and the land use patterns of the Plaster
Creek Watershed, we have determined that most of the E. coli
introduced to the creek appeared to be from areas of heavy
agriculture.
Creek Channel
Tributaries
800
700
600
500
E. coli (CFU/100mL)
Introduction
400
300
200
100
0
Suburban - 1
Suburban - 2
Healthy Ravine - 3
Commercial - 4
Industrial - 5
Industrial - 6
Agricultural - 7
Agricultural - 8
Agricultural - 9
Location
Figure 4. Comparison of the average of three E. coli samplings for nine tributaries of Plaster Creek and their
accompanying downstream reaches in the main creek channel with standard error bars.
Discussion
Coliform Sampling
Although dangerously high throughout the main channel, E. coli
levels in Plaster Creek seemed to concentrate in the southern,
upstream portion of the creek. The land usage of this region
suggests an agricultural source of E. coli. Although determining
the source of the bacteria requires further analysis. However, the
geographic information of this study provides Plaster Creek
Stewards with preliminary information, helping them consider
the best ways to address the residents of the area as they devise
best management practices for the area.
Special Thanks
Mike Ryskamp (Plaster Creek Stewards)
Joe Rathbun, Chad Kotke, Dana Strouse (Michigan DEQ)
Randall DeJong PhD (Calvin College)
Scott Jones, (Former Calvin College Biology student)