1 / 12

GIS-based Hydrologic Modeling in Watershed Management

Explore the use of GIS in addressing water quality issues in impaired water bodies, focusing on the Clean Water Act and TMDL. Understand the modeling approach, solutions, and challenges in watershed management.

dollys
Download Presentation

GIS-based Hydrologic Modeling in Watershed Management

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. GIS-based Hydrologic Modeling Jan Boll and Erin Brooks Biological and Agricultural Engineering University of Idaho

  2. The Environmental Problems • The Clean Water Act • ~1,000 water bodies impaired • Total Maximum Daily Load (TMDL)

  3. The Need • Development of water quality management plans to address non-point source pollution • Management scale: watershed area contributing to water body • Proper loading allocation for individual land owners • What are the critical areas in watersheds?

  4. Solutions to the Problem • Basin/Watershed Advisory Groups • Reconnaissance and monitoring • Modeling

  5. Modeling in General • “A model is a replica of a known system” • Used for hypothesis testing: empirical relationships to complex model • Used as a predictive tool: extensive testing and accurately producing a particular output for certain conditions

  6. About GIS • A tool to • Create and store watershed data • Perform spatial analysis • Display results • Make use of remote sensing technology

  7. GIS-based Modeling: Advantages • Provide simple and clear algorithms in model calculations • Identify and display high-risk areas • Rapidly evaluate management practice effectiveness or perform risk analysis • Efficiently present results to end user

  8. GIS-based Modeling: Assumptions • Divide the watershed into grids or elements • Within element: continuum assumption • Deterministic approach • Response is combined action of constituent process representations • Spatial variability of a watershed can be represented by distributed values of the model parameters at the model scale • Approach is referred to as distributed-parameter, physically-based modeling

  9. GIS-based Modeling:Reality Check • Many processes are not well understood at the watershed scale • Input data and model parameter estimation determine model complexity • Modeling using GIS does not necessarily improve model predictions • GIS offers a convenient modeling environment that appeals to end-user

  10. Scientific Approach Today’s Approach? Nature Nature Model Model no no yes yes Modeling Approach

  11. Watershed scale • Field/watershed scale • Field scale • Laboratory scale Dr. Jan Boll’s Research Program • Hydrology • Sediment • Phosphorus • Pathogens • Integrated System Approach to Watershed Management

  12. Model Classification • Based on • Processes: lumped vs distributed deterministic vs stochastic vs mixed • Scale: space (small-, medium-, large-sized) vs. time (event-based, continuous-time, large time-scale) • Method of solution: numerical, analog, analytical

More Related