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Map of SE Florida showing NNCS ship track lines for day 1 (blue line) and day 2 (green line), outfalls (black Δ), inlets (black ►), reef sites (red ס), background sites (magenta □). The ADCP locations are given by “x”.
NNCS field work map

The Southeast Florida coast includes the counties of Miami-Dade, Broward, and Palm Beach (~25.6 to ~26.9°N latitude), containing about 142 km of coastline extending approximately parallel to the flow of the Florida Current to the east. The region contains three non-continuous reef tracts (Banks et al 2008), containing ecosystems of significant economic, ecological, and aesthetic value to the 5.5 million residents therein (Johns et al. 2001, Gregg 2013). This area also contains significant point sources of pollution, i.e., five important ocean inlets and six treated-wastewater outfalls (Koopman 2006) and two ocean dredged materials disposal sites (ODMDS) (Figure 1). The task of conserving and managing this important ecosystem is performed by Florida's Department of Environmental Protection, including developing a consistent and effective regulatory process. In the past, standards for inland and coastal water quality were written as narrative standards, i.e., in no case shall nutrient concentrations of body of water be altered so as to cause an imbalance in natural populations of flora or fauna (FDEP 2009). The primary "nutrients" referred to are nitrogen and phosphorous. A decision was made (in conjunction with the U. S. Environmental Protection Agency) to replace the narrative standards with numeric nutrient criteria (NNC) for these variables (Sloan and Hulbert, undated). Three different approaches to developing NNC have been promulgated (EPA 2010): 1) the reference condition approach, which employs observations in minimally disturbed conditions within a region; 2) the mechanistic modeling approach, that develops relationships between stressors and ecological effects; and 3) empirical stressor-response modeling, in which sufficient data is available to accurately relate stress (e.g., N and P concentrations) to a measured ecosystem response. Each of these procedures requires a sufficient data set of relevant chemical, oceanographic, and biological data from the region; in particular, nutrient concentrations and ecosystem response measurements. FDEP determined that the nutrients will be TN and TP, with chlorophyll-a and in situ coral reef assessments providing the ecosystem response measurements.

NOAA-AOML's FACE group began a project in October of 2014 to assist in providing data that would be used in the development of the NNCs as described above. A series of twelve (bimonthly) water quality cruises were conducted on the R/V Hildebrand from November 2014 to September 2015, obtaining water samples via bottle casts at reef sites (Emerald Reef, The Pillars, Barracuda Reef, and Oakland Ridge), three coastal inlets (Port Everglades, Backer's Haulover, and the Port of Miami), two treated-wasterwater outfall sites, and six background sites (Figure 1). In addition, a series of coral assessments dives were conducted on those reefs. Ocean current measurements were made at two locations via acoustic Doppler current profiler (ADCP) instrumnetation.

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Banks, K.W., B. M. Riegl, V. P.. Richards, B. K. Walker, K. P. Helmle, L. K. B. Jordan, J. Phipps, M. S. Shivji, R. E. Spieler, and R. E. Dodge, in B. M. Riegl and r. E. Dodge (eds.), Coral Reefs of the USA, Springer Science + Business Media B. V., 2008.
Johns, G. M., V. R. Leeworthy, F. W. Bell, M. A. Bonn, 2001. Socioeconomic study of reefs in Southeast Florida, Final Report, Hazen and Sawyer, 348 pp.
Gregg, K., 2013. Literature review and synthesis of land-based sources of pollution affecting essential fish habitats in southeast Florida. Report for NOAA Fisheries Southeast Region , Habitat Conservation Division, West Palm Beach, FL, January 2013, 55 pp.
B. Koopman, J. P. Heaney, F. Cakir, M. Rembold, P. Indeglia, and G. Kini, 2006. Ocean Outfall Study Final Report. Prepared for the Florida Department of Environmental Protection, Tallahassee, Florida, april 18, 2006.
FDEP, State of Florida Numeric Nutrient Criteria Development Plan, March 2009
Sloan, M., and J. Hulbert (undated). Florida's Numeric Nutrient Criteria Development Plan. Downloaded from http://www.dep.state.fl.us/water/wqssp/nutrients.
EPA, Using stressor-response relationships to derive numeric nutrient criteria, EPA-820-S-10-001, 2010
Frydenborg, R., FDEP Division of Resource Assessment and Management, personal communication
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