      
|
Assessing the Long-Term Hydrologic Impacts of Land Use Change in the Wildcat Creek watershed using web-based GIS and spreadsheet version of L-THIA : a users perspective
This project was done using readily available data sets that could be gathered from local municipal planning offices and other public agencies for the spreadsheet and the GIS version of the Long-Term Hydrologic Impact Assessment (L-THIA) model. All the analysis was carried out using the web based version of the model that are available at : http://danpatch.ecn.purdue.edu/runoff
Land use data from four years was used to evaluate the change in runoff and non point source pollutants in the watershed. GAP land use data was obtained from Purdue’s online GIS data base that is available for public use at http://danpatch.ecn.purdue.edu/~caagis .The 1992 land use was generated by manually interpreting historical aerial photographs of the watershed. Current land use layer was prepared by going to the field and updating the map generated from the aerial photographs of 1992. The proposed land use map was obtained from the local municipal planning office in paper format and transformed into digital data to be used for the analysis (details of which are described in a later section of this paper).
Soil data for the watershed was also obtained from Purdue’s online database. This information can also be obtained from local Soil and Water Conservation District (SWCD) Offices.
The study was done to evaluate the long-term impact that land use changes in the area have had on the Wildcat Creek watershed and what impact the proposed development (based on future land use zoning information) will have on the watershed. Based on the data gathered (described above) analysis was also done to evaluate how the non point source pollutants in the watershed have changed over time and how the balances are likely to change in the future.
