The Science Plan
Over the past 20 years, the nation has invested in the NAWQA program to probe the status of, trends in, and understanding of the nation’s water quality. This investment in NAWQA has resulted in methodological advances (e.g., national sampling protocols, analytical methods, groundwater field investigative tools), conceptual and intellectual advances such as the development and implementation of predictive tools (e.g., models), and national syntheses of critical water quality topics. Now, NAWQA is the nationally-recognized program responsible for evaluating the nation’s water quality. To continue this evaluation into its third decade, the NAWQA Cycle 3 Science Plan contains four goals: 1) Data Collection and Trend Assessment, 2) Interpretation and Understanding of these data relative to land use and climate variability; 3) targeted studies for the Determination of the Cause-Effect Relationships of Multiple Stressors and Multiple Effects; and 4) using these data, understanding, and relationships to Forecast Future Trends of pollutants under different scenarios of land use, climate, and resource management.
NAWQA is poised, both within the USGS and the federal government, to continue the requisite sampling of our nation’s waters (Goal 1) to understand the interplay between the complex factors that affect water quality (Goal 2). The committee supports the continuation of these priorities including the choice of four major stressors (contaminants, streamflow alteration, nutrients, and sediment). Yet NAWQA is now also in a position to produce an even larger payoff. The program has reached a threshold in which the value of achieving Goals 3 (effects of stressors) and 4 (forecasting) is greater than that achieved by the sum of its parts. In other words, NAWQA has evolved from a water quality program emphasizing data collection and trend assessments to one that has the potential to predict and forecast pollutant occurrence and trends under multiple scenarios at nationally significant scales. The program’s scientific investments are maturing, enabling NAWQA to move past the current water quality monitoring to understanding the dynamics of water quality changes and using that understanding to forecast likely future conditions. By building on and maintaining the foundation from Cycle 1 and Cycle 2, NAWQA should move into the arena of “dynamic water quality monitoring” (Box 1). These are advances that the nation needs and the committee strongly supports.
Traditional Water Quality Monitoring vs. Dynamic Water Quality Monitoring
In Cycle 1 and 2, NAWQA assessed the status and trends of the nation’s water quality through a “Traditional Water Quality Monitoring” approach or by collecting data at regular intervals using a combination of fixed site and rotational sampling strategies. A “Dynamic Water Quality Monitoring” approach would assess the dynamics of water quality changes in addition to status and trends by a sampling design adaptable in both frequency and location overlaid on the traditional fixed sampling strategy. For example, changing sampling frequency to capture the dynamics of wet or dry spells associated with El Nino/La Nina events. By selectively increasing temporal and spatial resolution when and where it is needed, dynamic monitoring contributes to understanding of complex water quality phenomena and allows improved forecasting of likely future conditions.
The committee compliments the NAWQA Cycle 3 Team for envisioning a bold plan for the coming decade, with priority placed on dynamic water quality monitoring. Also, this version of the Science Plan responded to the comments made by the committee in the first letter report (NRC, 2010). Yet the Science Plan needs to continue to improve its clarity and NAWQA should continue to enhance the effectiveness of its communication of the ideas noted above. Although explaining the importance of the Cycle 3 goals and how NAWQA intends to accomplish these goals is essential, it is also critical to