Jeffery S. Horsburgh Utah State University Creation of a Google Maps Interface for Publishing Hydrologic Observations Data in the Little Bear River Jeffery S. Horsburgh Utah State University CEE 6440 Gis in Water Resources Final Project Presentation 11-27-2007

Little Bear River Test Bed One of 10 WATERS Network test bed projects funded by the National Science Foundation: projects focused on environmental observatory design. Developing a set of “smart” sensors connected to a central database. The sensors collect real-time, high frequency data of easily monitored variables.

Sensor Network 7 autonomous water quality stations measuring: Turbidity Water level pH Conductivity Water temperature Dissolved oxygen 2 weather stations measure a suite of meteorological variables Air temperature Barometric Pressure Solar radiation Relative humidity Precipitation Wind speed/direction

Monitoring and Telemetry Network Internet Map Server Observations Database (ODM) Base Station Computer ODM Streaming Data Loader Internet Monitoring and Telemetry Network Remote Monitoring Sites Data discovery, visualization, and analysis through Internet enabled applications Radio Repeaters Internet Map Server Central Observations Database

Objectives Create a simple to use website for plotting monitoring site locations and other useful geographic layers using freely available GIS technology Provide point and click access to the data collected at each monitoring site through a map based display Create the ability to display current conditions within the watershed for selected environmental variables Create the ability to query the observations data spatially and map monitoring sites where data is available for selected variables

Existing Map Server Technology ESRI ArcIMS Bear River Watershed Information System Older version of ESRI map server Browser as client Difficult to implement and maintain http://www.bearriverinfo.org

Existing Map Server Technology ESRI ArcGIS Server CUAHSI DASH Application Newest ESRI technology Spatial data plus spatial analysis Powerful but can be overkill Browser client http://his02.usu.edu/dash/

Existing Map Server Technology Microsoft Virtual Earth Hydroseek Freely available Browser client Requires programming No server overhead http://www.hydroseek.org

Google Maps http://maps.google.com Why Google Maps? Platform Independent (browser client) Freely available (no-cost license) Supports addition of GIS layers as KML Little overhead – do not have to configure or maintain the GIS engine!

The “Hello World” of Google Maps

Google Maps API Functionality JavaScript Application Programmer’s Interface Adding map controls Adding GIS Layers as KML Plotting points and adding custom HTML tags Adding event “listeners” to capture user clicks

Adding Layers as KML Several step process: Reproject layers to Geographic, WGS 84 Symbolize in ArcMap Export from ArcMap as KML – ESRI Arc Scripts! Copy KML files to server where they are publicly available Create JavaScript code to add layers var geoXml = new GGeoXml("http://water.usu.edu/littlebearmap/kml/watershed.kml"); map.addOverlay(geoXml);

Little Bear River Map Server Demo http://water.usu.edu/littlebearmap/

Discussion and Conclusions Demonstrates how environmental observations data can be published through a GIS map based interface that: Provides simple point and click access to the data Removes some barriers to efficient data access: Discovering which data are available and where they were collected Platform independent access through a web browser

Discussion and Conclusions Google Maps Pros and Cons Pros: Freely available Relatively simple to use with JavaScript Little overhead/licensing issues Flexible Nice imagery Cons: Limited cartographic layers Addition of layers via KML slows it down Size limits to KML files (~ 1 MB)

Questions?