Impacts of Land Use Change
on Water Resources

Determining Short-term Impacts

The short-term impacts of a change in land use can often be seen in the peak rate of runoff from an area. SedSpec is an expert system that will assist you in analyzing runoff and erosion problems on your site by determining the peak rate of runoff from the area. The analysis will provide information about different types of runoff and erosion control structures. Also, SedSpec will provide customized drawings of the structures, and there is a limited amount of interaction that allows you to determine what size structure fits your needs.

Determining Long-term Impacts

The long-term impacts of a change in land use can often be seen in the average annual runoff for an area. L-THIA (Long-Term Hydrologic Impact Assessment) is an analysis tool that provides site-specific estimates of changes in runoff, recharge and nonpoint source pollution resulting from past or proposed land use changes. It gives long-term average annual runoff for a land use configuration, based on climate data for that area. The user enters the location, land uses and soil groups of an area at up to three different scenarios (eg. past, present, future). The results are in the form of tables, bar charts and pie charts.