Geographic Information Systems

The use of Geographic Information Systems has become essential in water resources planning. The ability to assess changes in landuse over time within a large service area consisting of municipal, industrial, and agricultural users requires a powerful computer database. Key to the analysis is the integration of available landuse and forecast data with methods of water demand estimation.

SA uses the ESRI ArcView software for GIS. SA is also please to team with Ternary Spatial Research, TSR, a firm specializing in GIS applications in natural resource planning. TSR provides full ESRI Arc/Info UNIX support to the project in addition to ArcView.

Solution of planning issues using GIS technology involves the ability to import or modify existing data, and implement specific methods of analysis. There are many innovative methods for obtaining water demand study data. The Simons & Associates and TSR team can utilize various Geo-technologies for this purpose, including:
  • General vector GIS
  • General raster GIS
  • Aerial photography
  • Multi-spectral imagery
  • Global Positioning System (GPS)
Aside from collecting and using land use data in the traditional vector GIS format, there are several other means of collecting and using primary data. For instance, satellite imagery can be used to document change over time. A specific example of using this technology would be to characterize both existing and past land use within the study area using remotely sensed data and comparing this to other sources. This primary type of data gathering provides a check on the cultural imposition of classifications. Using imagery, it would be easy to detect how zoning and other land use controls had actually performed historically, giving insight into their effect on future land use. GPS technology could be used in a similar fashion to field gather primary land use data for comparative analysis.

A basic strategy of the SA/TSR team is to take maximum advantage of the flexibility provided by using GIS technologies. Key to this approach is the ability to combine data from multiple sources into a coherent usable dataset. Multitudes of data from very different sources can be combined and re-combined to model land use and provide inputs into other models. For example GIS can be used to take data from local governments combine them into a study wide coverage and then compare that to land use numbers that are held in Traffic Analysis Zones (TAZ) that the North Front Range Council of Governments maintains. Although this may be an unorthodox source for land use information related to water, it would provide an excellent check between the growth that the local agencies expect versus the expected regional picture. This ability to hone the data to be very accurate using several sources is something that other approaches cannot provide. Arc/Info and ArcView both support powerful programming tools (AML and Avenue script languages) for accomplishing these tasks. These tools can be used to create inputs to all types of models, physical process models, economic models, hydrologic models, etc. It is this flexibility that can be used to refine the inputs from many sources into one input into the demand study model. Using this inherent digital flexibility, many more iterations and/or scenarios can be generated to broaden the possibilities that are studied. Using accurate data collected from several sources, modeling future trends can be done with more certainty as it is not restricted by the amount of labor required to generate multiple datasets (for example by hand). Changes can be made "on the fly" to the database and the model can be run over and over until the results are satisfactory TSR has extensive experience in these programming tasks for water resources agencies. SA has extensive experience in applicable analysis methods. Together we can implement a wide range of methods for assessing current and future water demand, and associated issues such as reservoir operations and water rate structure.

GIS is also the best way to incorporate temporal information about continuing process into the study. Typically demand studies, like other studies, rely on a "snapshot" approach to data collection. Data collected in this fashion characterizes the land use or other component at a single moment in time. Our team's approach would include setting up the data as a constantly changing (updated) database that can direct water decisions over time. Rather than get a one time guess at what water consumption might be in a future horizon year, this study can set the stage for continued modeling and forecasting. So, as features change in the District and events happen (that might sharply change the water demand forecast) the GIS database can adapt. Our goal is to leave NWCD with a sophisticated tool to model water demand over time, at any time that such an estimate is needed or desired.

Back to Services Main Page

Home | Contact | Services | Brochure | Clients
All materials Copyright 1998 Simons & Associates