May 1995

Level of Gvt.: State, Federal

Function: Environmental protection

Problem/Situation: Too much data on Bay Delta

Solution: GIS helps organize and analyze data

Jurisdiction: California Department of Water Resources

Contact: Dept. Water Resources 916/653-7007.

By Alan Jones

California Department of Water Resources

To study the Northern California Bay-Delta ecosystem in depth and come up with a solution to the multiple and conflicting demands for development and preservation on it is nearly an impossible task - but one the California Department of Water Resources (DWR) must help to accomplish. The Bay-Delta includes rivers and streams which flow from the Sierra Nevada mountains to the Pacific Ocean near San Francisco. Monitoring and managing the huge area requires time, commitment and a new way of managing data with a Geographic Information System (GIS).

DWR's Division of Planning performs a variety of support tasks for Delta studies, including computer modeling, analysis and forecasting. But the data contributed by Planning staff is only a portion of what's available on the Delta and what's needed to tackle the region's difficult dilemmas. The question is how to manage enormous amounts of information from many different sources. To help with this Herculean task, a GIS database on the Bay-Delta ecosystem is being created by the Delta Planning Branch's Environmental Support Section.

"The GIS is one of many evolving tools that will help us manage the mass of complex data available," said Richard Breuer, an environmental specialist in Environmental Support coordinating the development of GIS with the University of California, Berkeley. "The system will help the department in working with other state and federal agencies to resolve Delta problems and make better decisions."

Planners will use this GIS to analyze data, make decisions and support those decisions, prepare environmental impact reports and statements, and monitor environmental mitigation in the Delta. They can import data from other public and private groups to build up the database, as well as add data gathered by DWR staff and other agencies working directly in the Delta, such as the state Department of Fish and Game, the State Lands Commission, and the U.S. Bureau of Reclamation.

"It also contains metadata," Breuer said of the GIS program. "That means the program will not only provide the facts but also the background behind those facts, such as: who collected them, what sampling method was used, are the data current and accurate? Metadata can help establish the credibility and significance of the data to be used for analysis."

Breuer prepared the agreement under which the UC Berkeley Center for Environmental Design Research will help develop the Bay-Delta GIS over the next two years. While several Division of Planning people are already familiar with GIS programs, Berkeley will train additional DWR staff to work with the new GIS.

How GIS Works

GIS works something like the human mind. It can take many sets of data and put them together in different combinations. For a researcher who knows what to look for, it can provide visual displays of the relationship between different data.

The technology, Breuer said, is different from other database systems because spatial, rather than linear, data is collected. Each bit of information - whether about wetland, habitat, distribution of a threatened species, location of a well, or land use - is linked by coordinates to the specific place where it exists in the real world. Features such as waterways, soil types or population density is stored in layers so analysts can pick and choose which data is observed.

GIS is a new way of assembling data and making it universally and instantly available. It's like being able to talk to everybody in