There's a hole in my -- and in the data as well!

This summer, HIS researchers will release “Version 1.1” of the HIS server software stack to eleven NSF hydrologic observatory test bed sites, after several months of collecting feedback from users and enhancing the overall system. Late last year, SDSC researchers installed the first version of the HIS server software – including databases, tools for web publishing of observations data, front-end applications and a comprehensive web-based data discovery and retrieval system - on dedicated servers before shipping them to the test bed sites, including one at UC Merced. The other NSF test bed sites are in Florida, Iowa, New York, North Carolina, Maryland, Minnesota, Montana, Texas, Utah, and Virginia.

At the core of the HIS system is WaterOneFlow web services, a set of web services for finding and retrieving hydrologic observations data in WaterML format. Under development by HIS researchers, WaterML is an Extensible Markup Language (XML) specification for exchanging water observations that is now being widely accepted throughout the hydrologic community. WaterOneFlow services provide access to large repositories of hydrologic observations maintained at federal agencies such as the EPA, USDA, USGS and NOAA, as well as numerous academic data collections developed in the course of university projects all over the country.

The ability to access this catalog and retrieve observations data from distributed repositories made this approach attractive to many developers and analysts. Environmental agencies in several states, including Florida, Texas and Idaho, are already working with the HIS team on incorporating their data repositories into the overall system. These agencies have plans to either install the HIS server software stack on their computers, or work with local universities on jointly managing access to their data collections

“We have had application interest from Arizona to Australia,” said Zaslavsky, adding that the HIS team at SDSC is offering server deployment and maintenance services to organizations interested in online serving and integration of hydrologic observations, including universities, local governments, community groups, and environmental consultants.

In addition, the USGS recently agreed to adopt the web services application programming interface developed under the HIS program, while the National Climatic Data Center (NCDC) began using CUAHSI’s WaterML specification for its Automated Surface Observing System (ASOS) last year. CUAHSI researchers are also working with the EPA to harmonize WaterML with the EPA’s WQX web services.

“We are extremely encouraged that the USGS and NCDC have chosen to adopt specifications developed within the HIS project,” said Zaslavsky. “Quite simply, the advancement of water science is directly dependent on the integration of all this data into a single representation as we seek the answers to key questions about our water supply.”

David Maidment, a world-renowned hydrologist from University of Texas at Austin, leads the overall project. Other key members of the CUAHSI HIS project include SDSC researcher and distinguished scientist Chaitan Baru; David Tarboton of Utah State University; Michael Piasecki of Drexel University; and Jon Goodall of University of South Carolina.