Your activity will be to examine the impacts of changing land use to low density urban land use and to compare those results with the higher density urban land use changes. You will need to go through these steps:
- Click on the link below to choose a scenario. Begin by choosing the Low Density Urban scenarios on the pull-down menu on that page. Start with the 10% scenarios. Start a spreadsheet or write down the maximum runoff depth and maximum flow associated with each scenario for each of the urban densities. Make sure you keep the name of the scenario with each set of numbers.
- Compare this to a few other scenarios with more urban land use. Calculate the absolute difference in the flows of each scenario compared with the 10% urban scenario.
- Look at the water quality graphs for the 10% scenario and one other urban scenario. Note what kinds of pollutants are generated and their peak amounts.
- Compare the agriculture scenarios with a low density urban scenario by going back to the page linked below. How does the urban land use impact flow compared with agriculture?
- Use the 90% urban scenario and play the flooding animation for that scenario. Does the change to urban land use of this amount cause any flooding in this watershed?
- Answer the questions below
- The land use changes that are simulated cause major differences in the streamflow. Explain why this happens in terms of the different parts of the hydrologic cycle that are altered because of the land use changes.
- Which pollutants are associated with urban runoff? How do they get into the stream?
- Why do the urban land uses cause a greater impact on runoff?
- What impacts does urban development at greater density have in relation to the lower density? Why do you think this is the case?