The backbone of the National Water-Quality Assessment (NAWQA) program has been the systematic collection and analysis of two decades’ worth of chemical, biological, and physical water-quality data using consistent and scientifically sound methods at a national scale. The program provides the majority of the nation’s information on the geographical occurrence of chemicals in the aquatic environment (streams, rivers, and groundwater). The first two decades of NAWQA’s effort provide a record of accomplishment that is too extensive to present in detail. Therefore, this chapter identifies 10 representative accomplishments of the program (Box 3-1) and assesses their significance, thus “assessing the accomplishments of the NAWQA program” per the statement of task. The order in which they are presented does not represent an evaluation of their relative significance.
Reports from individual study units in Cycle 1 established a baseline of water-quality in surface waters in distinct environmental settings with specific hydrogeology, climate, and anthropogenic factors. Data from all study units were combined to provide a national picture of NAWQA’s water-quality findings (Hamilton et al., 2004), which revealed that although most water in the United States is fit for most uses, contamination from point and non-point sources affects every study unit, particularly agricultural and urban areas. Contamination is generally a complex mixture of nutrients,
Accomplishments of the NAWQA Program
National assessment of chemicals in the nation’s surface water: NAWQA has provided a national picture of surface water quality.
National assessment of chemicals in the nation’s groundwater: This picture extends to the quality of the nation’s groundwater, giving the scientific and regulatory communities and the public an understanding of the nation’s water quality. Specific to groundwater, NAWQA has demonstrated the utility of groundwater age determination in water-quality studies, especially mixing of old and young waters.
Incorporation of biological indicators of water quality into assessments: NAWQA has integrated measures of indicator organisms into water-quality monitoring and has examined relationships among biological, chemical, hydrological, and land-use parameters using uniform methods at a national scale.
National synthesis reports: These reports synthesize robust data sets using descriptive statistics to draw broad conclusions for the nation to help answer the question that led to the program’s development—what is the state of the nation’s water-quality?
Continuity and consistency in study methods and design: NAWQA uses standardized sampling regimes, network design, and analytical techniques to enable cross-site comparisons, as well as intensive site-specific and constituent-specific sampling to meet local and regional stakeholder needs, and national water-quality assessments.
pesticides, organics, and their breakdown products, which are often just as prevalent as the parent compounds. Contaminant occurrence is not limited to compounds currently in use: polychlorinated biphenyls, chlordane, dieldrin, and other organochlorine compounds that are now restricted still persist in streams and sediments. Spatiotemporal patterns in contamination correspond with the timing of chemical application, hydrologic events (e.g., snowmelt) and land management practices. Thus, NAWQA provided a picture of water quality nationwide, giving the scientific and regulatory communities and the public an idea of the nation’s water quality.
NAWQA’s continuing focus on pesticides built on the assessment of pesticides in the nation’s surface waters and groundwaters from 1991 to 2001 (Gilliom et al., 2006). More recent analyses identify trends in pesticide and herbicide concentrations in streams and rivers in the Corn Belt from 1996 to 2006 (Sullivan et al., 2009). Regulatory and economic
Development and use of robust extrapolation and inference-based techniques: NAWQA has done an exemplary job of developing and applying robust extrapolation and inference-based models (e.g., SPARROW and the Watershed Regression for Pesticides or WARP models that are statistical, geospatial, and/or process-based and that support inferences from recent and historical data and projections of the outcome of proposed actions).
Information dissemination: NAWQA’s communication activities have grown in scope and sophistication as the program has evolved. The program now uses multiple media and appealing graphics to communicate its information products and tools, and it has a wealth of publicly available water-quality data in its data warehouse.
NAWQA science informing policy and management decisions: The program has translated and interpreted its high-quality, nationally consistent data with sophisticated tools so that policy and decision makers can use the program’s science to inform efficient decision-making.
Collaboration and cooperation: NAWQA continues to cooperate, coordinate, and collaborate within its own agency as well as with other federal, state, and local agencies in designing and carrying out its programs with a commitment to enhancing its usefulness by making its data and programs relevant to others with interests in water-quality.
Linkages and integration across media, disciplines, and multiple scales: NAWQA has been successful in multidisciplinary research at regional and national scales, collecting and interpreting geographic, hydrologic, biologic, geologic, and climatic data from a range of environmental media (e.g., groundwater, sediments, soils, surface waters, and biota) to help resolve water-quality questions.
changes caused major reductions in the application of some pesticides, with corresponding declines in surface water concentrations of those compounds (Gilliom et al., 2006). The NAWQA program’s findings also highlight how the movement of nitrogen and pesticides from agricultural fields to streams, groundwater, and beyond is controlled by a complex yet identifiable interplay of hydrologic factors (irrigation, drainage, flow paths, precipitation), agricultural practices (compound applied, timing of application), and biological processes (photosynthesis, biological activity) (McCarthy, 2009).1
Water-quality improvements from reductions in pesticide use are not limited to agricultural areas. After a federally-mandated phase-out of the organophosphate insecticide diazinon in outdoor urban settings, the concentration in northeastern and Midwestern streams fell dramatically
(Figure 3-1), and the frequency of exceedance of the acute invertebrate water-quality benchmark (1 µg/L) in summer samples fell from 10 percent to less than 1 percent (Phillips et al., 2007).
To further advance the assessment of chemicals in the nation’s surface waters, NAWQA scientists have used lake sediment cores to reconstruct water-quality histories. Accumulation rates for metals such as cadmium, chromium, copper, lead, mercury, nickel, and zinc have generally decreased since the 1970s, although accumulation rates in urban sediments can still be hundreds of times higher than rates in undeveloped watersheds (Mahler et al., 2006). Polyaromatic hydrocarbons (PAH) concentrations (associated with sediment) in cities where asphalt-based sealcoats are used are much lower than where coal-tar-based sealcoats are used (Van Metre et al., 2009). NAWQA also provides data gathering and sampling site assistance for work done by researchers in the U.S. Geological Survey (USGS) Toxics Program (Kolpin et al., 2002), which provided the first national-scale snapshot of the occurrence of contaminants of emerging concern.
Overall, NAWQA’s surface water-quality monitoring efforts provide an invaluable data set of surface water-quality conditions across the nation. NAWQA uses these data to provide regional and national assessments of great value. Although publications detailing some Cycle 2 studies are still
forthcoming, the program has already made significant steps toward being able to answer specific policy-relevant or national questions about surface water-quality.
USGS has been successfully conducting groundwater studies for more than 100 years. Indeed, the “father of groundwater hydrology” was Oscar E. Meinzer, employed by USGS from 1910 to 1940 and who served as the third USGS Ground-Water Division Chief. USGS was the first governmental agency to systematically apply science to studying groundwater systems, and its regional assessments of groundwater resources remain a hallmark of how hydrogeologic synthesis is done, including the use of a broad range of USGS publicly available groundwater numerical and geochemical models, and other groundwater assessment tools.2
NAWQA’s groundwater work builds on the USGS’s strength in this field. NAWQA initially focused on how human activities affected groundwater quality in agricultural and urban areas, excluding considerations of surface water-groundwater interactions (NRC, 2002). However, the connection between groundwater and surface water makes it difficult to achieve understanding if the resources are treated independently, so NAWQA adopted a process-based approach during Cycle 2 to characterize and model surface water-groundwater interactions in all appropriate study units (NRC, 2002).
NAWQA has integrated groundwater elements into its studies, even those that do not specifically focus on aquifers. NAWQA’s national synthesis reports on pesticides, volatile organic compounds (VOCs), and nutrients have all included important groundwater components. NAWQA’s groundwater work is particularly important because little such work on groundwater quality has been done systematically at a large scale. For example as part of the national assessment of pesticides (Gilliom et al., 2006), NAWQA reported that 55 to 61 percent of shallow groundwater samples in urban and agricultural areas contained one or more pesticide compounds, compared with 29 to 33 percent of samples from undeveloped or mixed land use areas (McMahon et al., 2008). VOCs were detected in aquifers across the United States, although concentrations were below a detection threshold of 0.2 ppb in 80 percent of the wells (Zogorski et al., 2006).
The characterization of groundwater quality in regional aquifers builds upon a study conducted in the High Plains Aquifer (McMahon et al., 2007) designed to exploit existing data to improve understanding of regional groundwater quality and flow, particularly with respect to aquifer vulner-
ability to contamination (USGS, 2005). Modern agriculture and particularly irrigation practices have increased the concentration of nitrates and dissolved solids in shallow groundwater, especially in areas where the local hydrogeology is conducive to fast transport of chemical species. Water supply pumping schemes that mix deep and shallow groundwater often produce lower-quality water than those that pump from deep wells alone. Furthermore, changes in land use such as conversion of rangeland to irrigated crops can affect local shallow groundwater quality (Gurdak et al., 2009). This type of regional analysis connects groundwater characterization efforts on many levels (e.g., private wells, public wells, age dating, flowpath modeling) and enables informed management decisions (e.g., reducing the risk of groundwater contamination by supply well pumping schemes or decreasing transport of untreated runoff to susceptible topographic lows).
Through the Topical Study Contaminant Transport and Public Supply Wells, NAWQA scientists have demonstrated the utility of groundwater age distribution determination in water-quality studies, especially mixing of old and young waters (McMahon et al., 2008). NAWQA has further advanced the science so that particle-tracking numerical models can be used to generate age distributions of groundwater entering a public supply well, not simply groundwater ages (Ehberts at al., 2012). A public supply well with a high fraction of young water might indicate a susceptibility to contamination initiated by a land-use change, whereas a public supply well yielding very old groundwater might be less susceptible to that contamination source.
The efficacy of this approach was dramatically illustrated by McMahon et al. (2008), who studied public supply wells in four aquifers. The modeled water-quality response to measured and hypothetical land use changes was dependent upon the age distributions of groundwater captured by the public supply wells and upon the temporal and spatial variability in land use in the source areas contributing to the wells. The time scales for public supply wells water-quality changes could be on the order of years to centuries for land use changes that occur over days to decades. These findings have implications for policy- and decision-making in relation to source water protection strategies that rely on land use change to attain water-quality objectives.
The hyporheic zone is the interface between groundwater and surface water where an exchange of chemical species, water, and organisms occurs (Gibert et al., 1990; Vervier et al., 1992). The connection between groundwater and surface water dictates that even in surface water supply and environmental flow studies, some knowledge of groundwater quantity and quality is essential. NAWQA researchers have advanced knowledge of exchange processes in the hyporheic interface. Recent studies include an examination of denitrification in the hyporheic zone of low-gradient nutrient-
rich streams (Puckett et al., 2008) and a demonstration of the usefulness of heat as an environmental tracer in surface water-groundwater quality studies, providing another tool for practitioners (Essaid et al., 2008). USGS pioneered hyporheic research, and now the importance of the hyporheic zone has been widely recognized and is currently being studied in research groups around the country (NRC, 2002).
NAWQA scientists have integrated biological assessments into water-quality monitoring and have examined relationships among biological, chemical, hydrological, and land-use parameters using uniform methods at a national scale. More than 450 publications have resulted from NAWQA’s ecological research,3 although much of the work is still forthcoming. The ecological condition is being assessed with metrics derived from samples of algae, macroinvertebrates, and fishes, which is an important and unique aspect of the NAWQA data. It is rare that all three are assessed in monitoring programs, although NAWQA data reveal that the three types of organisms seldom exhibit similar degrees of alteration in response to different land uses (e.g., Cuffney and Falcone, 2009). This implies that assessments based on only one type of organism may misjudge the extent and severity of impairment. Additional findings are that hydrologic alteration and land use change are the major drivers of alterations in ecological condition.
Ecological work in Cycle 2 included topical studies and program efforts encompassing four research areas: effects of urbanization on stream ecosystems, effects of nutrient enrichment on stream ecosystems, mercury in stream ecosystems, and effects of hydrologic alteration. Some of this work is highlighted here.
NAWQA’s Effects of Urbanization on Stream Ecosystems Topical Study studied how stream ecosystems respond physically, chemically, and biologically to urbanization, and how these responses vary in different geographic settings (Cuffney and Falcone, 2009; Giddings et al., 2009; McMahon, 2000; McMahon and Cuffney, 2000; Tate et al., 2005). NAWQA documented how regional patterns of development and regional differences in past and present land use (e.g., history of agriculture in the watershed) affect the response of biota to urbanization (Brown et al., 2009). Earlier researchers had suggested that the first signs of degradation appear when impervious surface cover reaches approximately 10 percent (Booth and Jackson, 1997; Schueler, 1994), but recent NAWQA studies found a continuous linear decline rather than a threshold (Brown et al., 2009; Cuffney
et al., 2005). A predictive model has also been developed, allowing prediction of benthic invertebrate response to urbanization at basin or regional scales based on parameters that describe the environmental setting, including antecedent agricultural conditions (Kashuba et al., 2010).
The Topical Study Effects of Nutrient Enrichment on Stream Ecosystems examined the influence of natural and human-related factors on nutrient cycling in stream ecosystems in agricultural watersheds differing in crop types (row crop, orchard, vineyard, pasture), animals (beef and dairy cattle, poultry), irrigation practices (none, central pivot, furrows), tillage, and amount of fertilizer applied (Munn and Hamilton, 2003). These agricultural streams often have nutrient levels in excess of U.S. Environmental Protection Agency (EPA) nutrient guidelines and show a limited ability to remove excess nitrogen through algal productivity or denitrification, leading to elevated downstream transport of nitrogen (Duff et al., 2008; Frankforter et al., 2009). Recent NAWQA publications have begun to examine indicators and indices that could be used to relate nutrient conditions with biological conditions, land use, and habitat factors (Frankforter et al., 2009; Justus et al., 2010; Maret et al., 2010).
The past two decades have seen advances in scientific understanding of mercury occurrence and behavior in standing water bodies; in recent years, NAWQA researchers have made contributions to the state of knowledge through the Topical Study on Mercury in Stream Ecosystems. NAWQA has documented the occurrence and speciation of mercury in fish flesh, bed sediment, and stream water (Bauch et al., 2009; Scudder et al., 2009). NAWQA’s analysis of recent and historical data for mercury in fish flesh (Chalmers et al., 2010) found that sites with decreasing trends in fish mercury outnumbered those with increasing trends by a factor of 6 between 1967 and 1987, demonstrating the effectiveness of the regulatory controls on mercury releases to the environment implemented during the 1970s. In a three-part article series NAWQA scientists described the chemistry and transport of mercury (Brigham et al., 2009) and contributed to understanding of the physical and biological factors that control the fate of mercury in stream ecosystems (Chasar et al., 2009; Marvin-DiPasquale et al., 2009). Drawing on multiple lines of evidence, the researchers concluded that the dominant factor controlling mercury concentrations in top predator fish is the amount of methylmercury available for uptake at the bottom of the food chain (Chasar et al., 2009).
The ecological effects of altered hydrology were studied using geospatial data to develop models predicting metrics of magnitude, frequency, duration, timing, and rate of change of streamflow (Carlisle et al., 2009). These models enable estimation of the natural flow regime, which is essential for estimating predisturbance conditions and for predicting natural flow characteristics at ungaged sites. A potentially significant quantitative
tool for assessing ecological condition is the current effort to understand the relationship among land use, climate change, and streamflow alteration and to quantify relations between streamflow alteration and biological impairment (Carlisle et al., 2011).
Overall, the NAWQA ecology program has developed nationally consistent measures of the status of primary producers, macroinvertebrates, and fishes in rivers and streams. This has enabled a more complete and integrated assessment of the health of rivers and streams than would be possible with physical and chemical analyses alone. NAWQA’s application of regression analysis and modeling of ecological data have facilitated identification of indicators and indices and may allow the development of predictive models. NAWQA’s urban studies have contributed to the scientific community’s efforts to advance integrative scientific understanding of urban streams (e.g., Wenger et al., 2009).
NAWQA’s National Synthesis Assessments and capstone reports use descriptive statistics to compare study unit data and other historical data (i.e., land use) to draw broad conclusions for the nation—a unique niche for NAWQA. National synthesis teams are able to write these reports because each NAWQA investigation adheres to a nationally consistent study design and employs uniform methods of data collection and analysis. NAWQA’s ability to organize itself around these themes in contrast to a more traditional project-by-project approach represents a major organizational accomplishment. These reports help answer the original NAWQA question: what is the state of our nation’s water quality? These reports identify water quality issues that occur only in isolated areas versus those that are pervasive, and they show the effects of human activities and natural factors on water quality in a range of environmental settings. Three national synthesis reports have been published (pesticides, VOCs, and nutrients), one is in progress (ecology), and the fate of the fifth (trace elements) is unclear.
The Pesticide National Synthesis Project4 and corresponding national synthesis report, Pesticides in the Nation’s Streams and Ground Water, 1992-2001, provides information about the occurrence of 75 pesticides and 8 pesticide degradates in agricultural, urban, undeveloped, and mixed land-use areas (Gilliom et al., 2006). Analytical methods “were designed to measure concentrations as low as economically and technically feasible,” and results were assessed using human health, aquatic-life, and wildlife benchmarks. Pesticide concentrations in streams and groundwater were characterized by land use and geographic patterns in pesticide use as well
as seasonal variations. Because of the 10-year sampling period, trends in concentration and aquatic life over time were detected and correlated to pesticide use.
The Volatile Organic Compounds National Synthesis Project5 and corresponding national synthesis report, The Quality of Our Nation’s Waters—Volatile Organic Compounds in the Nation’s Ground Water and Drinking-Water Supply Wells, presents information about the concentrations of 55 VOCs in aquifers, considering factors such as geography, aquifer characteristics, VOC type, detection frequency, and well type (Zogorski et al., 2006). This information was used to examine associations between natural and anthropogenic factors and the 10 most frequently detected VOCs. Many of these VOCs are solvents and industrial chemicals that are of concern for aquatic and human health in drinking water sources. These associations should help federal, state, and local agencies design sampling programs to detect contamination.
The Nutrients National Synthesis Project6 and corresponding national synthesis report, Nutrients in the Nation’s Streams and Groundwater, describes nutrient occurrence, source, effects on humans and aquatic ecosystems, and trends in concentration between 1992 and 2004 (Dubrovsky et al., 2010). Median concentrations of total phosphorus and nitrogen in agricultural streams were six times greater than background levels. However, exceedence of the federal drinking water standard for nitrate as N (10 mg/L) is uncommon in streams used for drinking water and deep aquifers; this standard was exceeded in more than 20 percent of shallow7 domestic wells in agricultural areas. Data for nitrogen and phosphorus show minimal changes in concentration in the majority of streams over the time frame studied, but more upward than downward trends occurred in those streams that did change in a statistically significant manner.
In the late 1980s when discussions about a national water-quality assessment were gathering momentum, federal agencies could not answer the question of whether the 1972 Clean Water Act was producing the intended improvements in water quality nationwide (Knopman and Smith, 1993). A national-level water-quality assessment was not possible because of analytical inconsistencies and a multitude of sampling networks designed for other purposes and ultimately unsuitable for spatial or temporal compari-
7 Less than 100 feet below the water table.
sons. For example, USGS collected water quality data through the stream benchmark program in largely pristine small watersheds, in the National Stream Quality Accounting Network (NASQAN) program at the mouths of major river systems, and in its many cooperative study projects with states and local governments where sampling designs and constituents measured were largely problem-driven and particular to the place. EPA, states, and local governments collected water-quality data for monitoring and compliance purposes. Sampling at a given site was often started and stopped, depending on the project duration and funding, and hence few sites had sufficiently long records of consistent analysis to enable valid trend analysis at a national scale. Inconsistencies in data collection included differences in how a sample was taken from a stream, how the sample was handled after collection, and what analytical methods were used to measure chemical and biological constituents. A compelling original argument for NAWQA was USGS’s ability to sustain a consistent, geographically diverse, and quality-assured data collection over decades, and follow through on a scientifically valid study design.
Since the program’s infancy, NAWQA has standardized sampling regimes and network design to enable cross-site comparisons to meet local and regional stakeholder needs, but at the same time to enable a national water-quality assessment. NAWQA brought order to a wide range of practices and motivations in water-quality sampling and analysis. NAWQA uses USGS approved methods that have been developed and tested by USGS researchers and approved for use at a national scale. These methods are periodically published in the USGS National Field Manual for the Collection of Water-Quality Data (USGS, variously dated). NAWQA now provides a nationally consistent data collection and analysis of water-quality samples (Gilliom et al., 1995). In setting this example and working with other groups on consistent practices, NAWQA has also helped to improve the water-quality monitoring efforts of other entities. This is a significant and enduring accomplishment.
NAWQA products are used to assess status and trends in water quality, to evaluate the effectiveness of regulatory programs, to inform policy analysis, and to support ecological risk assessment. For each of these applications, it is essential that data from a limited sampling of environmental attributes be put in geographical and climatic context with the uncertainty of inferences reported. NAWQA has developed and applied robust extrapolation and inference-based techniques that are statistical, geospatial, and/or process-based. These various models support inferences from recent
and historical data and projections of the outcome of proposed actions. Using these techniques to define the quality of our nation’s waters has added depth, both in space and in time, to the NAWQA assessment of U.S. water quality. Here two such models are highlighted, SPAtially Referenced Regressions on Watershed Attributes (SPARROW) and Watershed Regression for Pesticides (WARP).
The application of the SPARROW model (Smith et al., 1997) is an excellent example of USGS research and development leveraged by NAWQA. Although SPARROW was not developed under NAWQA, the program’s extensive use and support for improvements has made the model increasingly valuable. SPARROW’s capacity for quantitative evaluation of the origin, fate, and transport of contaminants in streams has pioneered a new way to investigate watersheds. SPARROW was designed as a national model to estimate long-term average values for water contaminants by relating in-stream water-quality and flow measurements with information about upstream sources and watershed characteristics. SPARROW assesses nutrient-source contributions, transport, and water-quality conditions at the national level, allowing estimation of nitrogen and phosphorus fluxes in unmonitored streams across the nation and enabling researchers to identify major nutrient sources and estimate nutrient fate in receiving bodies (Smith et al., 1997; USGS, 2009b). The model can be used to assess how large-scale changes in land use may affect future nutrient loading. NAWQA has refined the national model to study nitrogen delivery from the Mississippi River basin to the Gulf of Mexico (Alexander et al., 2000; Brezonik et al., 1999; USGS, 2009b).
NAWQA continues to transform SPARROW and explore this valuable tool. For example, the program is refining SPARROW to study various water-quality parameters in six of the eight Cycle 2 Major River Basins (MRBs). For future versions of SPARROW, NAWQA plans to incorporate updated geospatial and stream-monitoring data and to add temporal resolution that will facilitate analysis of decadal and seasonal change (USGS, 2009b). Also, NAWQA scientists are developing the SPARROW decision-support system, to bring the use of the model to the user through a USGS-supported web-based tool. (For more information, see Box 4-1 in Chapter 4.) SPARROW provides an important resource for evaluating and implementing management strategies; it integrates and benefits from data collected by collaborating agencies; and it is used by other organizations to help them meet water-quality objectives. Furthermore, it has the potential to contribute to all three of NAWQA’s initiatives: status, trends, and understanding.
The WARP models are statistical/geographic information system models used to assess pesticide concentrations in unmonitored streams (Stone and Gilliom, 2009). To date WARP models have been used to probe agricultural
applications of atrazine in streams, one of the most extensively used herbicides in the United States (Stone et al., 2008). Like SPARROW, these models, too, serve an important national purpose and may prove to be as useful as SPARROW in the future. For example, WARP models have recently been improved by developing region-specific models that include watershed characteristics that influence atrazine concentrations in the Corn Belt (“WARP-CB” models). The uncertainty for the regional WARP-CB models is lower than the national WARP models for the same sites (mentioned above and in Chapter 2), a promising development in terms of better prediction of atrazine in streams and for future WARP models of other pesticides (Stone and Gilliom, 2012).
Effective communication of findings is critical to the success of a program like NAWQA and contributes to its perceived relevance and usefulness. This is because, as noted in NRC (2002), NAWQA is “first and foremost a provider of information to parties interested in water quality.” Early in NAWQA’s history, communication was promoted as a fourth unspoken NAWQA objective (apart from status, trends, and understanding). Since then, NAWQA communication activities have grown in scope and sophistication starting with the user-friendly, non-technical Delmarva Circular in 1991 (Hamilton and Shedlock, 1992). NAWQA has been a leader within USGS in developing new tools and approaches to communicating with its various audiences of federal agencies, local and state cooperators, public officials, and the general public.
NAWQA’s communication activities have grown in scope and sophistication as the program has evolved so that these activities now represent one of the program’s significant achievements despite the fact that a small percentage (1 to 2 percent) of the program’s budget goes toward communication. In 2001 NAWQA released approximately 1,000 written publications. By January 2012 this number had grown to approximately 1,900, a publication every 4.2 days on average, a value that, while not an indicator of quality, provides a sense of the quantity of work produced over the history of the program. NAWQA is at an important junction in which key work for Cycle 2 is coming to completion and the program is launching a larger than normal amount of products as well as significant capstone products. NAWQA has 125 additional publications planned through 2012 as Cycle 2 draws to a close, pushing this total to more than 2,000 publications in the 20-year history of the program (Table 3-1).
Today, when NAWQA publishes a study, it produces a suite of publications and outreach activities according to a set communication plan designed to reach a variety of users. This communication plan uses a tiered
TABLE 3-1 Summary of NAWQA Publications by Type During the Pilot Phase, Cycle 1, and Cycle 2 through January 2012. More detailed information about publication types is included in Appendix C.
|Scope and Primary Contents
publications to be
completed in Cycle
2 (January 2012–the
end of FY 2012)
|Open File Reports||6||192||47||5||250|
|Conference Proceeding Papers||2||111||33||0||146|
|Data Scries Reports||0||1||26||4||31|
|Scientific Investigations Maps||0||0||4||0||4|
|Techniques and Methods Reports||0||0||3||0||3|
|Digital Media (audio, video,
|Other (Professional Paper,
Thesis, Water Supply
Papers, Newsletters, Non
aNon-USGS reports indicates references produced outside of USGS that include either NAWQA data and/or are coauthored by NAWQA personal, are about NAWQA, or are an interview with NAWQA personnel.
approach ranging from detailed scientific reports for technically trained audiences to one-page fact sheets and press releases for lay audiences. This includes informing the U.S. Congress; the program participated in approximately 25 congressional briefings throughout the history of the program (P. Hamilton, personal communication, May 13, 2009). Some of the work has been remarkably well cited in the scientific community, for example, Effect of stream channel size on the delivery of nitrogen to the Gulf of Mexico (Alexander et al., 2000) was cited 442 times as of August 20, 2012, according to Web of Science.
Perhaps the most notable strides in NAWQA’s communication efforts during Cycle 2 were through the use of digital media and appealing graphics to communicate its information, products, and tools. NAWQA’s home page is its primary web-based interface, which presents NAWQA publications, updates on recent findings, and links to project pages.8 During Cycle 2, NAWQA improved the program’s website by designing a more consistent look and feel to the individual web pages, improving access to information through national maps, creating web pages dedicated to individual topics, expanding related and embedded links through the site, and enhancing and expanding publication querying services. One notable example is the homepage of the Topical Study Contaminant Transport and Public Supply Wells.9 Public use of the NAWQA website has increased since 2006, with most hits after release of reports (Figure 3-2); for example, there were approximately 60,000 requests after the release of SPARROW results listing the watersheds contributing most to nutrients in the Gulf of Mexico.
The USGS Office of Communication is developing a social media presence using a Facebook page, YouTube, and Twitter. This includes promoting NAWQA studies to the larger USGS audience, when appropriate. NAWQA and the USGS Office of Communication jointly develop video podcasts on various NAWQA studies as part of the USGS CoreCast series.
The NAWQA data warehouse10 makes data widely available online with sufficient nodes for data approximating national coverage and, in some cases, with sufficient regional coverage to assess changes in water quality over time in major watersheds. It contains data on approximately 2,000 physical, chemical, and biological water-quality parameters (Bell and Williamson, 2006). Samples are from 7,300 stream and 9,800 wells as well as 3,000 bed sediment and tissue samples. Data include nutrient analyses for 66,000 samples, pesticide analyses for 44,000 samples, and VOC analyses for 12,000 samples. NAWQA biological information is
available through the newly released BioData Retrieval System.11 During Cycle 2, the data warehouse was improved with user-friendly mapping. The dissemination of NAWQA data via accessible databases enables scientists and regulatory agencies to place water-quality changes in geochemical and land-use contexts.
NAWQA was created to support scientifically sound decisions for water-quality management, regulation and policy. NAWQA has translated and delivered its interpretation of program data to the policy- and decision-
makers who need it. Better science does not guarantee better policy, but NAWQA’s data and scientific expertise inform efficient decision-making and thus have the potential to save resources. This is a significant program accomplishment. NAWQA tracks how its science and activities are used in decision-making and groups its contributions into 10 categories (Box 3-2).
Federal agencies including EPA, the National Oceanic and Atmospheric Administration, the Centers for Disease Control and Prevention, and the U.S. Department of Agriculture depend on NAWQA data for work on topics including nutrients, pesticides, stream protection and restoration, best management practices, fish consumption advisories, and even environmental factors related to nationwide cancer incidence. For example, the SPARROW model made substantive contributions to understanding of nitrogen and phosphorus sources and transport in the Mississippi River basin (Alexander et al., 2008). The study has major implications for “dead zone” hypoxia in the Gulf, and it will continue to help scientists and policy makers develop cost-effective nutrient management and reduction strategies in more than 800 watersheds within the largest drainage basin in the nation (USGS, 2010). Indeed, the federal interagency Mississippi River/Gulf of Mexico Watershed Nutrient Task Force is using this and other informa-
The NAWQA Program’s Science and Activities
That Support Policy and Management
• “Assessing sources and transport of contaminants in agricultural and urban areas;
• Assessing vulnerability to help prioritize geographic areas, basins, and aquifers for management and protection;
• Understanding trends and whether conditions are better or worse over time;
• Assessing source-water quality used for drinking;
• Assessing and sustaining aquatic ecosystem health;
• Linking tributaries to receiving waters;
• Support for the development of regulations, standards, guidelines, and criteria for contaminants;
• Contributions to state assessments of beneficial uses and impaired waters (Total Maximum Daily Loads or TMDL), strategies for source water protection and management, pesticides and nutrient management plans, and fish-consumption advisories;
• Improved strategies and protocols for monitoring, sampling, and analysis;
• Communication of findings for policy and management.”
SOURCE: USGS, 2010.
tion to make recommendations for action in the basin. More than 10 states and tribes use NAWQA data to meet EPA requirements, especially related to Total Maximum Daily Loads (USGS, 2010). The use of SPARROW also extends to understanding sediment loading in the Chesapeake Bay (Brakebill et al., 2010) and the sources of salinity in the southwest (Anning et al., 2007).
Decision-making, regulatory, and advisory bodies from local councils to state legislatures in more than 30 states also use NAWQA science to the benefit of public health and water resource management (USGS, 2010). NAWQA’s work has enabled improvements in areas such as source water protection, quality assurance, quality control, sampling design, sampling methods, analytical protocols, and interpretation frameworks for the water resources issues that states and local governments confront. States save resources by using NAWQA data for these purposes. Washington and New Jersey have both used NAWQA data to obtain compliance monitoring waivers from the EPA for low vulnerability water supply wells under the Safe Drinking Water Act. Organizations like the Wind River Environmental Quality Commission of the Shoshone and Arapahoe Tribes in Wyoming use NAWQA’s data to meet federal reporting requirements.
NAWQA has a history of cooperating and collaborating within its own agency, the Department of the Interior, and with other federal, state, and local agencies in designing and carrying out its programs. Those efforts to establish cooperative relationships have been recognized in past reviews (NRC, 2002, 2009). The following assessment from NRC (2002) remains true today:
NAWQA has become a model of an effective, collaborative federal program—an attribute policy makers always stress, but seldom achieve. NAWQA has successfully integrated its program both within and outside of the USGS, establishing some exemplary relations with EPA and state governments.
NAWQA has continued to improve its efforts in this area during Cycle 2. NAWQA sites are coordinated with USGS’s National Stream Accounting Network (NASQAN), thus strengthening the program’s surface water network from within the agency. One particularly noteworthy product of external collaboration resulted from combining data from EPA’s Wadeable Streams Assessment (WSA) and NAWQA to develop predictive models that provide taxon-specific measures of probability of capture, which were used to assess the biological condition of streams in several land use categories (Carlisle and Hawkins, 2008). The addition of NAWQA reference sites to
the WSA model increased the range of environmental conditions to which the model could be applied.
Collaboration with the National Research Program and the Toxic Substances Hydrology Program have provided NAWQA scientists with new analytical methods, assistance in model development, and access to the latest insights from basic research. The committee heard from representatives of federal agencies (e.g., several program offices in the EPA, the U.S. Fish and Wildlife Service), states, and non-profits (e.g., the H. John Heinz III Center for Science, Economics and the Environment) that testified to the productive and collaborative relationships they have developed with NAWQA. Input from collaborators was essential to the development of the Cycle 3 Science Plan. These and other examples in Chapter 5 illustrate NAWQA’s ability to collaborate with other programs and its commitment to enhancing its usefulness by making its data and programs relevant to others with interests in water quality.
NAWQA has been successful in multidisciplinary research at the regional and national scales, integrating geographic, hydrologic, biologic, geologic, and climatic data, to resolve water-quality questions. NAWQA has collected and interpreted data from a range of environmental media including groundwater, sediments, soils, surface waters, and biota and focused attention on linkages between groundwater and surface water. NAWQA investigations consistently recognize the interrelatedness of processes occurring in aquatic and terrestrial environments that impact water quality. For example, NAWQA’s work on mercury spans media including water column and suspended particulate matter (Brigham et al., 2009), sediment pore water (Pasquale et al., 2009), and fish and invertebrates (Chasar et al., 2009). These studies permit a holistic assessment of the complex dynamics and impact of mercury at the ecosystem scale.
NAWQA has successfully linked the disciplines of surface water and groundwater hydrology, chemistry, and biology. It is only through this multidisciplinary approach that the complexities of contaminants that cycle (e.g., metals and nitrate) and their impact on biota can be determined or that the relation between hydrology and contaminant transport can be quantified (Tesoriero et al., 2007). Because NAWQA designs, implements, and interprets study data with teams consisting of hydrologists, chemists, and biologists, the resulting reports offer cohesive and high-impact information on the complex interactions between chemicals and the physical and biological media through which they pass and interact.
NAWQA is uniquely positioned to collect and interpret data from
scales ranging from single rivers and watersheds (Duff et al., 2008) to larger basins and aquifer systems, and finally to the entire nation (Lapham et al., 2005; USGS, 2008). Most NAWQA studies are conducted in systems that cross political boundaries (e.g., Alexander et al., 2008) and over time scales that range from short term (days to months) to years (Van Metre and Mahler, 2005) and decades (Mahler et al., 2006). NAWQA continuously and consistently collects and interprets data over time scales that are relevant to hydrogeologic processes and the impact of human activities on them. Studies mentioned in earlier sections have benefited from the enhanced spatial (e.g., urban stream studies) and temporal (e.g., principal aquifer studies) perspective. NAWQA is uniquely positioned to carry out complex, interdisciplinary work at scales that are not possible to achieve by individual academic or government scientists.
NAWQA has achieved a national water-quality assessment. This judgment is based on the committee’s review of NAWQA achievements (Chapter 3), stakeholder assessments of the program heard in testimony, information contained in the NAWQA Science to Policy Management document (USGS, 2010), and the results of two NAWQA Customer Satisfaction Surveys (mentioned in Chapters 4 and 5). The committee concludes that in Cycles 1 and 2, NAWQA provided a successful national assessment of U.S. water quality, in accordance with the mission of a national water-quality assessment program.