Researchers help county balance water and growth equation

Population growth in a city or county often is a sign of health--a positive reflection of a region's economic, social, environmental and other "quality of life" features. But for many municipalities, maintaining a healthy balance between regional growth and natural resource management is increasingly difficult.

In King County, Wash., which includes the expansive Seattle metropolitan area, the county's Department of Natural Resources and Parks is looking to Pacific Northwest National Laboratory for assistance with a new approach to planning and resource management. PNNL is working with the county to develop a computational modeling system that predicts the potential impacts of urban activities, including growth, on the area's watersheds, lakes, estuaries and rivers.

"Ecologically, King County is a very diverse area. From the Cascades to the Puget Sound, there are multiple watersheds, rivers and large lakes, all of which are important to the region. And in the middle of this, we have the Seattle metro area," said David Thurman, a PNNL senior research scientist leading the modeling system project. "Managing growth and planning for the future are significant challenges in King County and many other areas of the United States."

PNNL began working with the county in 2000 to lay the groundwork for the Integrated Water Resource Modeling System (IWRMS), which should be completed within the next two years. The system will offer a modular, distributed software architecture that supports the incorporation of legacy and newly developed computational water resource models and data sets into an integrated whole that can be accessed via individual computer workstations.

Initially, IWRMS will include the Hydrological Simulation Program-FORTRAN watershed model, lake and river models developed by the U.S. Army Corps of Engineers and human and ecological health risk models yet to be developed. Once the IWRMS is operational, the county will be able to integrate additional data and models--everything from simulations of urban growth and land-use effects on watersheds to water flow and quality in rivers, lakes and estuaries--into the system, which will provide automatic data transformation between models. The resulting system will enable the county to better understand how potential development actions might affect water resources and other elements of the environment.

"It could be used to evaluate diverse scenarios such as drinking water withdrawal from urban lakes or discharge of treated water on agricultural fields. The goal of the system is to provide a flexible modeling environment the county can adapt to a variety of scenarios, enabling production of scientifically valid modeling results in a timely fashion," Thurman said. "Our goal isn't so much to develop a system, but to help the county build a problem-solving capability."

Approximately a dozen researchers located at PNNL's Seattle and Richland, Wash., campuses are developing the system in partnership with county staff. To date, much of the project has focused on defining the system requirements and establishing interactions with "stakeholders"-- or the various county staff who will be using the system and its outputs. Several prototype systems will be delivered to the county over the next couple of years and fine-tuned based on feedback from the users. The final system not only will provide valuable new capabilities to the county, but will significantly reduce the amount of time needed to produce useful data and, possibly, lead to quicker, more effective decision making.

"We believe this type of system would be valuable to many municipal governments who are wrestling with complex growth and natural resource management issues and who have a desire to use computational models to help inform their decision making," Thurman noted.