Browsing by Author "Erickson, Timothy O."

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    Baseflow Analysis of the Upper Vermillion River, Dakota County, Minnesota
    (St. Anthony Falls Laboratory, 2008-06) Erickson, Timothy O.; Stefan, Heinz G.
    Estimates of groundwater recharge are important for water resources planning and management, e.g. to determine the sustainability of groundwater resources. Estimates of groundwater recharge can be obtained by streamflow, especially baseflow, analysis. The Vermillion River, located at the southern fringe of the Minneapolis-St. Paul Metropolitan Area, is a DNR-designated groundwater-fed trout stream. How the stream flow in the Vermillion River and its tributaries is affected by urban development encroaching into the watershed is a pressing question. The baseflow in the Upper Vermillion River was therefore analyzed to determine the river’s groundwater recharge and minimum flow potential. The study site watershed includes approximately 129 square miles of the 338 square miles of drainage area within Dakota and Scott Counties. Two methods, the baseflow-separation method and the recession-curve-displacement method, were applied to the streamflow data from the USGS stream gauging site #05435000 near Empire, MN, to estimate baseflow and groundwater recharge in the Upper Vermillion River. The USGS computer programs PART and RORA were used to perform the baseflow analysis. The results of the analysis were used in conjunction with a water budget to estimate other hydrologic variables in the Upper Vermillion River basin at the annual timescale. It was determined that about 24% of the average annual precipitation reaches the stream as either baseflow or direct runoff. About 20% of the annual precipitation or approximately 80% of the annual streamflow in the Upper Vermillion River is baseflow from cold groundwater sources. The average annual estimates were found to compare well with results of previous studies (Baker et al. 1979, Ruhl et al. 2002, Lorenz and Delin 2007).
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    Groundwater Recharge in a Coldwater Stream Watershed during Urbanization
    (St. Anthony Falls Laboratory, 2009-01) Stefan, Heinz G.; Erickson, Timothy O.
    Urban development of rural land is of concern for water resources. The quantity and quality of surface runoff and groundwater recharge can be significantly affected by urbanization. Base flow in streams and cold water habitat, e.g. for trout, depend on groundwater. If water recharge to aquifers is reduced, and surface runoff is increased, cold-water fish habitat can be adversely affected. The change to groundwater recharge resulting from the urbanization of a rural/natural area in the Vermillion River watershed in Minnesota was investigated. The Vermillion River is a groundwater-fed designated trout stream at the southern fringes of the Minneapolis/St. Paul metropolitan area in Minnesota. In this watershed urban development has encroached on farmland and natural areas in the last 25 years. The process is projected to continue into the future. Three studies related to groundwater recharge were conducted: (1) a soil water budget study to estimate the influence of changed imperviousness and surface vegetation on natural recharge in a small tributary watershed of the Vermillion River, (2) a trend analysis of stream/base flow at the USGS stream gauging site on the Vermillion River near Empire, MN, and (3) a water use study to estimate the influence of imported water on artificial recharge stemming from. The results of the first study confirm that the increase in impervious surface area associated with urban development will decrease annual natural groundwater recharge. The trend analysis (second study) showed no statistically significant trend in the streamflow record during the period of 1982 to 2006 even though imperviousness in the watershed increased from 8% in 1984 to 13% in 2005. The third study revealed that groundwater recharge from urban water supply and drainage systems and from irrigation has more than doubled from 1982 to 2006; it accounts for nearly 10% of annual recharge in the watershed and matches the reduction in natural recharge predicted by the soil water budget models (first study). The net effect of urbanization on groundwater recharge, seen in the trend analysis of the Vermillion River base flow was close to zero.
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    Stream Temperature Modeling of Miller Creek, Duluth, Minnesota
    (St. Anthony Falls Laboratory, 2009-10) Herb, William R.; Erickson, Timothy O.; Stefan, Heinz G.
    This report summarizes a modeling study of heat loading and stream temperature in Miller Creek in support of the MPCA Miler Creek temperature TMDL. The MINUHET surface runoff modeling tool was used to characterize runoff temperatures for typical residential and commercial watersheds for the continuous period June 15 to September 15, 2008. These results were then generalized to the entire Miller Creek watershed using runoff volumes from a SWMM model developed at SAFL. These simulated runoff temperatures and volumes were then used to estimate point source heat loadings to Miller Creek for the same time period. Separate models for wet detention ponds, infiltration basins, and underground stormwater vaults were used to estimate possible reductions in heat loading from surface runoff. Standard wet ponds were found to increase overall heat inputs, but reduce peak heat loading rates and maximum stream temperature increases due to stormwater. The use of wet ponds with bottom outlet structures and underground vaults gave some reductions in effluent temperature for smaller rainfall events (< 1 cm), but were of little benefit for larger events. Infiltration practices give the greatest benefit in reducing temperature impacts of runoff, by direct reduction in runoff volume, however, widespread implementation of infiltration practices in the Miller Creek watershed may be difficult.
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    Streamflow Modeling of Miller Creek, Duluth, Minnesota
    (St. Anthony Falls Laboratory, 2010-01) Herb, William R.; Stefan, Heinz G.; Erickson, Timothy O.
    A Storm Water Management Model (SWMM) was constructed to model flow in the Miller Creek watershed using readily available data. Miller Creek is an urban trout stream flowing through Duluth/Hermantown, Minnesota. Miller Creek starts near the Duluth Airport, flows south through Duluth and discharges into the St. Louis River estuary of Lake Superior. In 2008 and near its mouth, Miller Creek had a mean annual flow of 9.1 cfs, a recorded peak flow of 291 cfs, and base flow of less than 0.1 cfs. Despite extensive commercial and some residential development in the Miller Creek watershed over the past 30 years, Miller Creek has still a naturally reproducing Brook Trout fishery. The urban development included the filling of wetlands to create parking lots, the removal of riparian tree cover, and the introduction of storm water runoff from impervious surfaces (SSWCD, 2001). These changes have lead to elevated stream temperatures, and consequently Miller Creek was put on the list of impaired waters by the Minnesota Pollution Control Agency (MPCA) in 2007. The Minnesota Pollution Control Agency (MPCA) has mandated a temperature Total Maximum Daily Load (TMDL) study. This report summarizes the development of a Storm Water Management Model (SWMM) for Miller Creek in support of the TMDL study. The model simulates continuous time series of stream flow at 15-minute time intervals in Miller Creek using observed precipitation, stream bathymetry, watershed hydrogeology, and tributary and storm sewer characteristics as input. The model was calibrated and validated against flow data from 2008, and is able predict mean flows, peak flows, base flows, and storm runoff volumes. The SWMM was also used to simulate the effect of a a few stream alteration scenarios on the streamflows in Miller Creek/
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    Streamflow Modeling of Miller Creek, Duluth, Minnesota
    (St. Anthony Falls Laboratory, 2010-01) Erickson, Timothy O.; Herb, William R.; Stefan, Heinz G.
    A Storm Water Management Model (SWMM) was constructed to model flow in the Miller Creek watershed using readily available data. Miller Creek is an urban trout stream flowing through Duluth/Hermantown, Minnesota. Miller Creek starts near the Duluth Airport, flows south through Duluth and discharges into the St. Louis River estuary of Lake Superior. In 2008 and near its mouth, Miller Creek had a mean annual flow of 9.1 cfs, a recorded peak flow of 291 cfs, and base flow of less than 0.1 cfs. Despite extensive commercial and some residential development in the Miller Creek watershed over the past 30 years, Miller Creek has still a naturally reproducing Brook Trout fishery. The urban development included the filling of wetlands to create parking lots, the removal of riparian tree cover, and the introduction of storm water runoff from impervious surfaces (SSWCD, 2001). These changes have lead to elevated stream temperatures, and consequently Miller Creek was put on the list of impaired waters by the Minnesota Pollution Control Agency (MPCA) in 2007. The Minnesota Pollution Control Agency (MPCA) has mandated a temperature Total Maximum Daily Load (TMDL) study. This report summarizes the development of a Storm Water Management Model (SWMM) for Miller Creek in support of the TMDL study. The model simulates continuous time series of stream flow at 15-minute time intervals in Miller Creek using observed precipitation, stream bathymetry, watershed hydrogeology, and tributary and storm sewer characteristics as input. The model was calibrated and validated against flow data from 2008, and is able predict mean flows, peak flows, base flows, and storm runoff volumes. The SWMM was also used to simulate the effect of a a few stream alteration scenarios on the streamflows in Miller Creek/�