**2. Key features of EPA's coastal assessments**

During the summer of 2010, nearly 50 field crews visited 1104 pre-selected sampling stations in U.S. estuaries and Great Lakes coastal waters. Onsite, the crews collected environmental data and sampled the water column, sediments, and benthic and fish communities. Preserved samples were shipped to a dozen or so laboratories for analysis, and laboratory and field data were ultimately compiled into databases for analysis and reporting. In the following sub-sections, we outline the NCCA procedures used to select sampling stations, collect samples and information onsite, and assess and report ecological conditions at various scales. Further details regarding the implementation and evolution of assessment methods are described in Section 3.

#### **2.1 Selecting sites**

The NCCA employed a rigorous design process to meet several key assessment goals. First, the coastal waters to be assessed—the *target population*—was precisely specified. The target population was carefully defined as: (i) all estuarine waters in the conterminous U.S. from the "head-of-salt" (landward extent of waters with salinity greater than 0.5 ppm) to the boundary with the open ocean and (ii) Great Lakes of the U.S nearshore coastal waters located within 5 km of shore and less than 30 m in depth. EMAP included some inland river sections, river mouths, tidal streams and ponds, and sections of the continental shelf. However, NCCA excluded such waters as tidal streams and deep central channels of major rivers and bays, non-estuarine shorelines to better accommodate state needs. A GIS file specifying the areal coverage of the study regions—the *sample frame*—was compiled for subsequent use in selecting sampling sites. The sample frame for the 2010 NCCA comprised an area of 91,700 sq. km of coastal marine and fresh water.

Next, sampling sites were selected using a probabilistic, stratified survey design. That is, the target region was divided into *strata*—multiple nested assessment units that fairly represented the nation and various subregions designated for evaluation [23]. The largest domains were the five reporting regions: (1) The Atlantic coast of the northeastern U.S. from Maine through Virginia (including Chesapeake Bay); (2) the Atlantic coast of the southeastern U.S. from North Carolina through Biscayne Bay in south Florida; (3) the Gulf of Mexico coast of the U.S. from Biscayne Bay through Texas; (4) the Pacific coast of the western U.S. from Washington through California; and (5) the U.S. coasts of the Great Lakes. These strata were subdivided to delineate the coastal waters of the 21 ocean states and the five Great Lakes, and some larger units were in turn further subdivided to highlight important water bodies or regions designated for special study. The 2010 NCCA sampling design recognized a total of 64 distinct strata, which could be combined as needed for analysis or reporting at multiple spatial scales. Survey planners specified the number of sites allotted to each stratum based on cost effectiveness and survey priorities. The five primary reporting regions and the distribution of sampling sites in the 2010 NCCA survey are shown in **Figure 2**.

Sample sites were then selected probabilistically, but not randomly, using a process termed the Generalized Random Tessellation Survey (GRTS) design [23]. The GRTS method employs an intricate algorithm that ensures uniform and unbiased station placement, thereby minimizing clumping that may result if sites were selected using a purely randomized approach. A weighting factor, called the *inclusion probability*, was provided for each site. The factor was calculated as the stratum area divided by the number of sites in the stratum and was used during the analysis stage to estimate regional condition (see Section 2.3).

**135**

*Lessons Learned from 30 Years of Assessing U.S. Coastal Water*

Finally, the survey design procedure identified both "base" and "oversample" locations. Sampling was mandatory at the base sites, and oversample sites were designated as replacements for inaccessible base sites or to be used by states in other regional assessments or enhancements. At least 50 base sites were allocated to each of the five reporting regions and to strata receiving an enhanced assessment. A sample size of 50 sites was considered adequate to yield results with reasonable statistical confidence [23]. Ten percent of the base sites were designated as "revisit sites", to be sampled twice during the same summer period in order to estimate intra-site variability. Additionally, 25% of sites were identified as "return sites"—stations to be repeatedly reassessed over the course of four subsequent NCCA surveys. These return sites increase the ability to quantify temporal variance and to aid in detecting change over time [24]. Further details of the entire NCCA site selection process is available in

*Location of the 1104 sites sampled in the 2010 NCCA survey, by reporting region.*

a non-technical overview of monitoring design topics provided online [25].

The 2010 NCCA survey was a highly orchestrated campaign mounted to assess the nation's coastal waters. Implementation included training field crews, documenting sampling and analysis methods, collecting information and physical samples onsite, coordinating sample analysis, building databases, and performing

Nearly 50 field crews composed of state, tribal, EPA personnel, and contractor staff, were deployed to collect samples and information during a summer *index sampling period*—June through September. Prior to the field season, the crews were rigorously trained by EPA trainers regarding NCCA protocols stipulated in the Site Evaluation Manual, Field Operations Manual, and Quality Assurance Project Plan [22]. During time on station, field crews would (i) record field conditions, including Secchi depth, vertical profiles of temperature, salinity, pH, dissolved oxygen, and photosynthetically active radiation (PAR) intensity; (ii) collect surface water samples for lab analysis of nutrients, chlorophyll, and human health indicators; (iii) collect grab sediment samples for analysis of contaminant concentrations, grain size, toxicity, and total organic carbon; (iv) collect and preserve separate sediment samples for characterization of the benthic macroinvertebrate community; and (v) collect fin-fish from within a proscribed distance from the site to characterize the local fish community and

provide tissue for analysis of lipid and contaminant content (**Table 1**).

**2.2 Implementing coastal surveys**

**Figure 2.**

quality assurance (QA) reviews.

*DOI: http://dx.doi.org/10.5772/intechopen.92326*

*Lessons Learned from 30 Years of Assessing U.S. Coastal Water DOI: http://dx.doi.org/10.5772/intechopen.92326*

*Water Quality - Science, Assessments and Policy*

in Section 3.

**2.1 Selecting sites**

**2. Key features of EPA's coastal assessments**

During the summer of 2010, nearly 50 field crews visited 1104 pre-selected sampling stations in U.S. estuaries and Great Lakes coastal waters. Onsite, the crews collected environmental data and sampled the water column, sediments, and benthic and fish communities. Preserved samples were shipped to a dozen or so laboratories for analysis, and laboratory and field data were ultimately compiled into databases for analysis and reporting. In the following sub-sections, we outline the NCCA procedures used to select sampling stations, collect samples and information onsite, and assess and report ecological conditions at various scales. Further details regarding the implementation and evolution of assessment methods are described

The NCCA employed a rigorous design process to meet several key assessment goals. First, the coastal waters to be assessed—the *target population*—was precisely specified. The target population was carefully defined as: (i) all estuarine waters in the conterminous U.S. from the "head-of-salt" (landward extent of waters with salinity greater than 0.5 ppm) to the boundary with the open ocean and (ii) Great Lakes of the U.S nearshore coastal waters located within 5 km of shore and less than 30 m in depth. EMAP included some inland river sections, river mouths, tidal streams and ponds, and sections of the continental shelf. However, NCCA excluded such waters as tidal streams and deep central channels of major rivers and bays, non-estuarine shorelines to better accommodate state needs. A GIS file specifying the areal coverage of the study regions—the *sample frame*—was compiled for subsequent use in selecting sampling sites. The sample frame for the 2010 NCCA

comprised an area of 91,700 sq. km of coastal marine and fresh water.

sampling sites in the 2010 NCCA survey are shown in **Figure 2**.

stage to estimate regional condition (see Section 2.3).

Sample sites were then selected probabilistically, but not randomly, using a process termed the Generalized Random Tessellation Survey (GRTS) design [23]. The GRTS method employs an intricate algorithm that ensures uniform and unbiased station placement, thereby minimizing clumping that may result if sites were selected using a purely randomized approach. A weighting factor, called the *inclusion probability*, was provided for each site. The factor was calculated as the stratum area divided by the number of sites in the stratum and was used during the analysis

Next, sampling sites were selected using a probabilistic, stratified survey design. That is, the target region was divided into *strata*—multiple nested assessment units that fairly represented the nation and various subregions designated for evaluation [23]. The largest domains were the five reporting regions: (1) The Atlantic coast of the northeastern U.S. from Maine through Virginia (including Chesapeake Bay); (2) the Atlantic coast of the southeastern U.S. from North Carolina through Biscayne Bay in south Florida; (3) the Gulf of Mexico coast of the U.S. from Biscayne Bay through Texas; (4) the Pacific coast of the western U.S. from Washington through California; and (5) the U.S. coasts of the Great Lakes. These strata were subdivided to delineate the coastal waters of the 21 ocean states and the five Great Lakes, and some larger units were in turn further subdivided to highlight important water bodies or regions designated for special study. The 2010 NCCA sampling design recognized a total of 64 distinct strata, which could be combined as needed for analysis or reporting at multiple spatial scales. Survey planners specified the number of sites allotted to each stratum based on cost effectiveness and survey priorities. The five primary reporting regions and the distribution of

**134**

**Figure 2.** *Location of the 1104 sites sampled in the 2010 NCCA survey, by reporting region.*

Finally, the survey design procedure identified both "base" and "oversample" locations. Sampling was mandatory at the base sites, and oversample sites were designated as replacements for inaccessible base sites or to be used by states in other regional assessments or enhancements. At least 50 base sites were allocated to each of the five reporting regions and to strata receiving an enhanced assessment. A sample size of 50 sites was considered adequate to yield results with reasonable statistical confidence [23]. Ten percent of the base sites were designated as "revisit sites", to be sampled twice during the same summer period in order to estimate intra-site variability. Additionally, 25% of sites were identified as "return sites"—stations to be repeatedly reassessed over the course of four subsequent NCCA surveys. These return sites increase the ability to quantify temporal variance and to aid in detecting change over time [24]. Further details of the entire NCCA site selection process is available in a non-technical overview of monitoring design topics provided online [25].

#### **2.2 Implementing coastal surveys**

The 2010 NCCA survey was a highly orchestrated campaign mounted to assess the nation's coastal waters. Implementation included training field crews, documenting sampling and analysis methods, collecting information and physical samples onsite, coordinating sample analysis, building databases, and performing quality assurance (QA) reviews.

Nearly 50 field crews composed of state, tribal, EPA personnel, and contractor staff, were deployed to collect samples and information during a summer *index sampling period*—June through September. Prior to the field season, the crews were rigorously trained by EPA trainers regarding NCCA protocols stipulated in the Site Evaluation Manual, Field Operations Manual, and Quality Assurance Project Plan [22]. During time on station, field crews would (i) record field conditions, including Secchi depth, vertical profiles of temperature, salinity, pH, dissolved oxygen, and photosynthetically active radiation (PAR) intensity; (ii) collect surface water samples for lab analysis of nutrients, chlorophyll, and human health indicators; (iii) collect grab sediment samples for analysis of contaminant concentrations, grain size, toxicity, and total organic carbon; (iv) collect and preserve separate sediment samples for characterization of the benthic macroinvertebrate community; and (v) collect fin-fish from within a proscribed distance from the site to characterize the local fish community and provide tissue for analysis of lipid and contaminant content (**Table 1**).


*a National Oceanic and Atmospheric Administration National Status and Trends Program analytes. Concentrations reported as dry weight of sediments and wet weight of tissue.*

#### **Table 1.**

*Indicators measured in the National Coastal Condition Assessment (NCCA) surveys.*

The field data were submitted as either physical or electronic data sheets to NCCA headquarters for compilation. Preserved water, sediment, and fish samples were shipped to approve national or state laboratories for analysis and results were submitted to NCCA headquarters. Each site generated hundreds of field and laboratory data values that were organized into files by type (e.g., field data, water quality data, benthic census data, etc.), and maintained as "raw files" in a centralized database by information management specialists. The raw files were then subjected to a stringent two-phase QA review process, first checking for basic compliance with submission requirements (e.g., proper units, range checks, and conformity with standard taxonomic terminology). Any revisions to the raw files were carefully documented, and finalized files were made available at the NCCA public website [26].

One of the hallmarks of the NCCA, and the NCA which preceded it, has been the emphasis on the cooperation and participation of the states and tribes in planning and conducting the assessment within their respective jurisdictions. Not only are states and tribes key to survey implementation, they are the entities responsible

**137**

Monitoring website [25].

conducted from 2010 onward.

*Lessons Learned from 30 Years of Assessing U.S. Coastal Water*

under the Clean Water Act (CWA), Section 305b, to report to Congress regarding the extent to which the nation's waters support the CWA goals. From the research and development phase to the current operational program, numerous workshops and training sessions have been held to build technical expertise regarding monitoring design, sampling, data analysis, and interpretation of results. Through this technical transfer, numerous organizations have modified their local monitoring efforts to incorporate NCCA methods and approaches to assessing the condition of coastal resources. State and tribal partners have been active participants in the ongoing assessments of the performance of current indicators, and in the selection and testing of developmental indicators needed to respond to emerging environmental issues.

Following the lead of earlier EPA coastal surveys, the NCCA approach had two primary goals regarding assessment: (1) evaluate the *status* of four major components of coastal ecosystems—the water column, sediment, and benthic and fish communities, and (2) ascertain how conditions *change over time (i.e., trends)*. For each of the key assessment components, conditions were evaluated based on a suite of core indicators and indices constructed from them. For instance, water quality was assessed using five measured indicators (concentrations of nutrients, chlorophyll, and dissolved oxygen, and water clarity) and a water quality index was then crafted from the five components. The assessment process first evaluated conditions at each site, rating each indicator and index as good, fair, or poor based on regionally determined assessment thresholds. Details regarding the indicators, indices, and thresholds used in assessments are presented in Section 3 of this chapter.

Once sites were evaluated, regional and national conditions were calculated. Recall that the survey design process had assigned each site a weighting factor equal to the area represented by the station. Regional assessments were then expressed as the percent of the region in good, fair, poor, or unassessed condition. For instance, the percent area of the Pacific coast in good condition was simply calculated as the sum of weighting factors associated with Pacific sites rated as good, divided by the total area of the Pacific coastal region (sum of all Pacific site weights). Assessments were calculated for the nation, for the five primary reporting regions (**Figure 2**), and for any state or desig-

The survey design procedure further provided a measure of the uncertainty in the condition estimates, expressed as the 95th percentile confidence interval (CI), which was calculated as the binomial proportion confidence interval adjusted for possible spatial gradients in indicator measurements [23, 27]. Operationally, the confidence intervals were calculated using a complex computer-intensive algorithm, coded in the R-programing language, available at EPA's Aquatic Resource

As the number of surveys conducted increases, the NCCA documents change over time. Typically, trends have been evaluated by analyzing what happens at an individual location, much as a physician monitors trends in the weight of an individual patient. In contrast, trends for NCCA were evaluated at the population level, i.e., trends in the proportion of sites in good condition. These population level trends were evaluated by noting statistically significant changes, i.e., condition estimates displaying non-overlapping CIs, determined over a series of comparable surveys. Since the early 1990s, coastal survey methods have evolved significantly over time. In some cases, new analyses can be applied to old data. In other cases, methodological differences have precluded trend analyses over the entire 30-year period. Eventually, trends in national assessments will reflect only NCCA surveys

nated research area containing a statistically-sufficient number of sites.

*DOI: http://dx.doi.org/10.5772/intechopen.92326*

**2.3 Assessing status and trends**

under the Clean Water Act (CWA), Section 305b, to report to Congress regarding the extent to which the nation's waters support the CWA goals. From the research and development phase to the current operational program, numerous workshops and training sessions have been held to build technical expertise regarding monitoring design, sampling, data analysis, and interpretation of results. Through this technical transfer, numerous organizations have modified their local monitoring efforts to incorporate NCCA methods and approaches to assessing the condition of coastal resources. State and tribal partners have been active participants in the ongoing assessments of the performance of current indicators, and in the selection and testing of developmental indicators needed to respond to emerging environmental issues.
