Effects of Urbanization on a Small Rural Watershed
File(s)
Date
2005-01Author
Rasmussen, Walter L.
Publisher
University of Wisconsin-Stevens Point, College of Natural Resources
Metadata
Show full item recordAbstract
The Moses Creek Watershed, northeast of Stevens Point, Wisconsin, although
quite small, has the potential for substantial downstream impact. The creek drains
directly into the storm sewer system for the City of Stevens Point. The storm sewers are
unable to handle the increased flow when flood potential is reached in the spring, and
after heavy summer rains. At this time there are few buffers to ease the threat of flooding
caused by Moses Creek; first, as it enters Stevens Point and second, as it enters the storm
sewer system. Possible solutions to abate flooding within Stevens Point would be
protection of the headwaters of Moses Creek and restoration of wetlands within the
watershed.
This study of Moses Creek will; gather stream flow and precipitation data for the
watershed, generate a database using appropriate software, evaluate hydrologic modeling
programs to determine the one best suited for Moses Creek, calibrate that model to
provide a realistic representation of the watershed, and use the model to simulate
potential future effects on the Moses Creek Watershed.
Precipitation and stream flow data were analyzed to determine the hydrologic
characteristics of the Moses Creek Watershed. These data were used to calibrate a runoff
model, the United States Army Corps of Engineers, Hydrologic Engineering Center - Hydrologic
Modeling System (HEC-HMS). Environmental Systems Research Institute
(ESRI) Arc View®, a software mapping tool using landuse, elevation, roads, soils, and
property boundaries, facilitates definition of watershed hydrologic parameters and allows
these parameters to be incorporated into HEC-HMS. The HEC-HMS model has shown a high degree of correlation between measured and modeled runoff. Agreement between
measured and modeled data make it possible to manipulate parameters of the modeled
watershed to evaluate the impact of land use changes in the actual watershed.
Model runs reveal that the Moses Creek Watershed is sensitive and variable to
subtle changes in characteristics of the watershed including precipitation, vegetation, soil
saturation, pervious cover or lack of it. Subtle character changes have dramatic influence
on downstream discharge volumes, duration of peak discharge and lag time between
rainfall event and flood event.