Esri News for Water Resources Winter 2012/2013 newsletterDocument Transcript
ArcGIS Online Floats River AnalysisBy Vladimir Moya Quiroga Gomez, Free Consultantfor Water ResourcesEsri NewsWinter 2012/2013The rivers and wetlands on the Bolivian Amazon Basin are subject toflooding. Rivers meander across the level landscape and continuouslychange course. This dynamic basin morphology creates economic andenvironmental loss. Floodwater covers large areas and impacts cities,farmlands, and natural land. These floods are lethal, drowning peopleand livestock and spreading dengue virus. Visualizing this dynamiclandscape with GIS helps people make decisions about where to liveand work. To demonstrate that hydrographic analysis can be done using acloud computing service, the author performed a study that could beuseful to local governments along Bolivia’s Ichilo River for planning This satellite image of the Ichilo River, shown in a spectral combination of bands 2, 4, and 7, reveals present and former flow paths and newvegetation cover (light color between purple and green). The user makes this land change information the basis for estimating future flow paths.continued on page 3
3Winter 2012/2013 esri.com/waterresourcesnews The user accesses ArcGIS Online from a smartphone, opens the Bolivian AmazonBasin Ichilo River application, and chooses the satellite imagery for the project. Usingtools to measure distances, the user has measured the probable cut of a meander neckat about 280 meters. By comparing imagery of current channel flowswith imagery from past years, the analyst can seehow the landscape has changed over the lastdecade. The probable flow area is calculated to beabout 15,134,085 square meters. With the distance measure tool, the user candetermine the distance from a river to a roadway.This helps plan road construction and estimatemaintenance.road construction. He used ArcGIS Online GIS tools and its collectionof global coverage maps and satellite imagery. He combined remotelysensed imagery and ArcGIS to see land topography that was otherwisehidden beneath vegetation and cloud cover. By combining differentbands of satellite images, the author easily identified land use, landcover, and soil types to see how they were affected by meanderingrivers and flooding. Once the author had created the application, he published it as aservice, making it available on the web and as a mobile application.Users can download the ArcGIS app for smartphones for free. Usingthe browser on the mobile device, the user accesses the map applica-tion and performs on-site analysis. For instance, with a measuring tool,a mobile user can determine the river’s current cutting distances toestimate future meander cuts.If you have questions, contact the authorat email@example.com.ArcGIS Online Floats River Analysis continued from page 1
GIS, GPS, and Lasers: Field Crews AccuratelyAssess the State of Northwestern WatershedsHuman activity such as logging and road building inevitably transformour environment, but federal agencies are collaborating to evalu-ate, protect, and restore some of the most vital and sensitive areas.Riparian zones—from the Latin word “ripa” meaning riverbank—referto rivers, streams, and surrounding land. They serve as habitats fordiverse flora and fauna and have far-reaching influence on soil andgroundwater conditions. When outside influences turn a lush, shaded,slow-moving stream into a barren bedrock chute, the entire watershedcan be impacted and invasive species can take over. The Northwest Forest Plan helps ensure that such scenarios areavoided—and even reversed. The plan’s policies and guidelinesempower federal agencies to work together toward more sustain-able management of federally owned lands that span from NorthernCalifornia to the Canadian border and from the Cascade Mountainswest to the Pacific Ocean. In the crucial area of watershed conserva-tion, their efforts are informed by comprehensive reports prepared bythe Aquatic and Riparian Effectiveness Monitoring Program (AREMP). Each summer, adventurous AREMP field crews employed by the USForest Service (USFS) and US Bureau of Land Management (BLM) setout to sample 28 watersheds, resulting in 250 watersheds sampledon a nine-year rotation. To determine monitoring site locations, theAREMP GIS team first identified watersheds with at least 25 percent oftheir stream channels lying within federal land. Of these watersheds,250 were selected for stream sampling using a process that ensured arandom, uniform distribution of watersheds throughout the NorthwestForest Plan area. Within each selected watershed, a similar processwas used to select a random, uniform sample of stream survey sites.Because many other agencies and organizations also use this methodto select study sites, AREMP findings contribute to richer overall knowl-edge about the sample areas and can help inform other environmentalefforts. AREMP crews measure a variety of attributes including the shapesand sizes of streams and rivers, the location and position of largewoody debris in the stream channel, and biologic factors such as thetypes of aquatic insects and amphibians that are present. The result isan overall stream score for each watershed that reveals its health andenables comparisons with previous conditions. The AREMP team’s findings help inform a variety of National ForestPlan efforts. Near Roseburg, Oregon, for example, before riparianzones were protected, logging activity resulted in decreased amountsof woody debris, altering the streams and making them less hospitableto the salmon that once thrived there. Federal and state governmentsand local nonprofit organizations placed trees and boulders in riparianzones to help build up substrate levels to create better fish habitats.Upon returning to sites like the ones in Roseburg, field crews foundthat the restoration work did in fact result in increased stream condi-tion scores. The AREMP team members also help look for the presence ofinvasive species. When they come across aquatic invasive species“Integrating the laser with everythingelse creates streamlined workflows.”Mark Isley, AREMP Data ManagerÔ Field crews use a laser and prism setup from Laser Technology, Inc.,to capture precise measurements of river and stream morphology,which are fed directly into a GIS.
AREMP Project Planning MapAREMP WATERSHEDSLand OwnershipBureau of Land ManagementForest ServiceNational ParkP r o j e c t A r e aP r o j e c t A r e a0 250 500125Kilometers§6 5 W a t e r s h e d s6 5 W a t e r s h e d sW a s h i n g t o nW a s h i n g t o n6 0 W a t e r s h e d s6 0 W a t e r s h e d sC a l i f o r n i aC a l i f o r n i a1 2 5 W a t e r s h e d s1 2 5 W a t e r s h e d sO r e g o nO r e g o n5Winter 2012/2013 esri.com/waterresourcesnewsduring their stream surveys, the appropriategovernment organizations are informed so theycan take immediate action before the problemworsens. After visiting 4 to 10 sites within a watershed,the crew moves on to the next watershed. To getto remote sites in places like Olympic NationalPark in Washington, which has some of thehighest watershed scores due to limited humanactivity, crews must hike 10 or more miles. Insome cases, horses are used to help transportsurvey gear to rugged sites. Crews work fromMay through September, with a few specialmonitoring projects extending into October. A key piece of the field data collection thatlays the groundwork for the surveys involvesmeasuring river or stream morphology. This cre-ates a map of the channel based on the width,depth, and path of the water and how it changesover time. To take accurate measurements,two crew members work together using a laserwith an electronic compass and prism setupfrom Laser Technology, Inc., called the MapStarImpulse System, which is waterproof and canbe mounted for extra stability on rough terrain.Measurements are immediately displayed on abacklit LCD display to ensure accurate readingsin shady environments like riparian zones. A built-in serial port brings the compassand laser data directly into surveying softwarerunning on Esri’s ArcPad platform on ruggedhandheld devices. Customized data inputforms specific to AREMP’s work automaticallyappear when a laser measurement is taken, andthe devices also record the location via a GPSsensor. These measurements are used to createa map using a toolbar extension for ArcPad called LaserGIS, providingcontext for each study site. Other crew members measure shade levels;sample for amphibians, invasive species, and small invertebrates like in-sects, snails, worms, and crayfish; and collect additional data. This datais input through custom ArcPad applets and forms and automaticallyrelated to the site map. “Integrating the laser with everything else creates streamlinedworkflows,” says AREMP data manager Mark Isley. “Sometimes we’llbe measuring channel widths that are a meter or meter and a half widewith a depth of 10 to 15 centimeters, so highly accurate laser offsets areimportant to us.” Along with the data collected in the field, the GIS team brings in ad-ditional datasets, including vegetation from remotely sensed imagery Every nine years, 250 sites are surveyedbetween Northern California and the Canadianborder. The collected data is combined with otherspatial datasets and remotely sensed imageryand analyzed in a GIS to better understand theconditions of northwestern watersheds.and GIS road layers from the BLM and Forest Service. This data enablesit to analyze key riparian factors across full watersheds, such as miles ofroad within riparian areas and the frequency of roads crossing streams.All this information together results in a comprehensive picture of thehealth of northwestern watersheds. The AREMP team’s hard work has not gone unnoticed. It hasreceived a Riparian Challenge Award from the Western Division of theAmerican Fisheries Society and a National Interagency Service FirstAward for its collaborative, multiagency monitoring program that sup-ports the success of the Northwest Forest Plan.
Flood Map Service Makes Data FlowBy Stefan Fuest, Fernando Salas, David Maidment, Daniel Siegel, Steve Kopp, and Matt Ables6 Esri News for Water Resources Winter 2012/2013When floods occur in central Texas, precipi-tation, streamflow, and floodwater eleva-tion data is captured by the US GeologicalSurvey’s (USGS) National Water InformationSystem, the City of Austin’s Flood EarlyWarning System, and the Lower ColoradoRiver Authority’s Hydromet system. The problem is that all these vital waterdatasets and maps are stored in disparate sys-tems and disseminated via individual websitesand data streams without a common interfaceto synthesize information; each system has itsown web page where data is accessible onegauge at a time. The solution for this problem is the CentralTexas HUB, an information system developedby the Center for Research in Water Resources(CRWR) of the University of Texas, Austin;KISTERS; and Esri. The system continuously“See spatial andtemporal flood datawithin a commongeographic interface.”ingests water observation data from variousdata providers into a central database main-tained by CRWR. Water Information KISTERS,primary engine for the database, stores thisdata, performs calculations, and outputsvalue-added information products on thefly, such as three-hour moving precipitationtotals. The HUB provides users with near real-timewater data and historical statistics, such asmean, maximum, and minimum values, whichprovide context and a basis for comparison ateach individual observation point. Users cansee data over time for a period of a week, amonth, or a year. The HUB also thematicallymaps all the data within the system by organ-izing streamflow, precipitation, and waterlevel data on individual GIS layers. Moreover,users can choose to combine or separate dataÔ Water discharge data is shown as a table,a chart, and a map.