Water Quality Modeling in New York/New Jersey Harbor: A Historical Perspective on the Present Robin Landeck Miller and James J. Fitzpatrick As HydroQual celebrates its 25th Anniversary as a corporation based in the New York-New Jersey metropolitan area, it is appropriate to reflect upon water quality in the New York-New Jersey Harbor. The waters of the New York/New Jersey Harbor complex provide a valuable resource to the New York metropolitan area and to the nation in general. Given the rapid growth in urban population, industrial development, and shipping and commerce within the region over the past three hundred years, it is not surprising that the waters of the Harbor have shown evidence of degraded water quality and significant environmental stress. Efforts to mitigate these problem have included a combination of regulatory controls and wastewater treatment plant construction. These efforts, which have largely taken place over the past forty to fifty years, have led to measurable and significant beneficial improvements in water quality. Mathematical, or numerical water quality, models have been a key tool for providing water quality managers insights into the relationships between pollutant inputs and water quality responses in the Harbor. The spatial resolution and environmental complexity of water quality modeling has grown from relatively simple steady-state, one-dimensional, coliform and BOD/DO models to complex time-variable, three-dimensional models, which include hydrodynamic, sediment transport, complex eutrophication/organic carbon production, contaminant fate and transport, and bioaccumulation frameworks. Beyond the New York/New Jersey Harbor, these frameworks are applicable to many urban waterways. HISTORY OF ISSUES, REGULATORY ACTIONS, FACILITY CONSTRUCTION, AND APPLICATION OF MATHEMATICAL MODELING ANALYSES The issues of waste disposal and water pollution were first noted in lower Manhattan during the time of the early European settlement. The first efforts to remedy these problems began in 1696 with the construction of a sewer and wastewater collection system. While sewer systems helped address the issue of waste disposal, they did not address the issue of water pollution, since the Harbor received untreated wastewater from the sewers. The waters of New York Harbor once supported a large and diverse community of fish, shellfish, and shorebirds. However, these resources began to decline as a result of pollution and habitat loss (Franz, 1982; McHugh et al., 1990). Legislative and regulatory efforts to quantify, control, and reduce pollutant inputs into New York/New Jersey Harbor have been taking place for almost a century. The first of these efforts took place in 1906, with the New York State legislature directing the formation of the Metropolitan Sewerage Commission of New York (now NYCDEP). Besides initiating routine water pollution surveys in 1909 (which represent the longest historical record in the United States), the Commission recommended upgrades in wastewater treatment, including construction of new wastewater treatment facilities. Beginning in 1956, federal programs provided municipalities with funding for the construction of wastewater treatment facilities and the management of receiving water quality. It
was during this period of time, between the late 1950s and the early 1970s, that the initial efforts to model water quality in New York Harbor were undertaken by Donald O’Connor (1962, 1966). O’Connor (1962) developed a one-dimensional steady-state BOD-DO model of the upper New York Bay and the Hudson River from the Battery to the City line at Yonkers. O’Connor (1966) expanded his first model to include the East River, the four wastewater treatment plants that discharged to the East River at that time (Wards Island, Bowery Bay, Tallman Island, and Hunts Point), the proposed Newtown Creek facility, as well as consideration of distributed sources from Manhattan, Brooklyn, and Queens and stormwater inputs. O’Connor constructed a four compartment or segment representation (Figure 1) of the upper harbor, the lower East River (divided above and below Newtown Creek), and the upper East River. The model’s analytical equations required the solution of a set of simultaneous linear equations. The model was calibrated and used to assess the relative contribution from each of the pollutant input sources, including sediment oxygen demand (SOD) due to sludge deposits. The earlier model developed by O’Connor (1966) was expanded (O’Connor and Mancini 1972), calibrated, and used to make projections of expected changes in dissolved oxygen levels in the Upper Bay, the North River, and the East River resulting from various load reductions in BOD discharges from the Passaic Valley (New Jersey), Newtown Creek, and the North River water pollution control facilities (WPCPs1). The authors concluded that regional planning and wastewater treatment was required in order to achieve water quality goals for New York Harbor. The 1972 Clean Water Act (CWA) provided funding for construction of municipal WPCPs and 208 studies. 208 studies are regional analyses of pollutant inputs and pollutant load reductions required to address water quality problems. The NYC 208 study was initiated in 1975 to assess the seasonal impact of continuous (domestic and industrial sources) and intermittent discharges, the latter including combined sewer overflows (CSOs) and separately-sewered stormwater sources. With the advent of (at the time) modern computers and newer mathematical modeling techniques, a high resolution finite-difference model of the Harbor was developed. The 208 model considered both BOD/DO and pathogens (total and fecal coliform). The 208 model, which included vertical segmentation for the Hudson River and Upper Bay, provided a first attempt to consider the effects of density-driven circulation and vertical stratification on water quality and, in particular, dissolved oxygen. The NYC 208 modeling package included a landside pollutant flow and load model, to account for the approximately 700 CSOs and storm sewers that drained to the New York Harbor system; a flow-routing module; and the receiving water quality model. The model was calibrated and validated against observed data from twelve periods spanning a range in temperature and Hudson River flow conditions. The NYC 208 model represented one of the first cases of the application of a well-verified, density-driven estuarine model to project water quality response to the control of continuous and intermittent wastewater sources. One of the key findings of the NYC 208 study was the deleterious impact on water quality of the discharge of CSOs in a number of tributaries (ex., Flushing Creek and Flushing Bay and Newtown Creek in the East River, and Paerdegat Basin, Thruston Basin, and Fresh Creek in Jamaica Bay, etc.). Efforts to correct these problems were deferred in favor of eliminating the discharge of 1
At the time this analysis was performed the North River WPCP had not been constructed.
raw sewerage to the waters of the Harbor. The discharge of raw sewage had been reduced from 1,070 mgd in 1936 to less than 1 mgd by 1993 (Brosnan and O’Shea, 1996b). Associated with this reduction in raw sewerage discharge and upgrades in treatment at the region’s WPCPs, the loading of BOD to harbor waters decreased almost three-fold from the highest levels observed in the midsixties (Suszkowski, 1990). These upgrades in wastewater capture and treatment have resulted in significant improvements in water quality throughout the Harbor (NYCDEP, 2002). However, urban tributaries and embayments of the East River and Jamaica Bay still demonstrate poor water quality and often fail to meet water quality standards for coliform bacteria and dissolved oxygen. These problems appear to be related to episodic pollutants inputs from wet weather combined sewer overflows. Facility plans for abating CSO discharges (Apicella et al, 1988, Apicella et al. 1993, Apicella et al., 1996, Apicella, 2001, HydroQual, 1990, 1991) were developed. For the most part the models used to investigate these water quality issues continued to use relatively simple coliform and BOD/DO kinetic frameworks. In addition, water quality problems exist in the western portion of Long Island Sound and the Grassy Bay section of Jamaica Bay. These waters fail to meet water quality standards for dissolved oxygen. However, nutrient enrichment and not simply anthropogenic inputs of organic carbon appears to be the more important factor contributing to the contravention of the dissolved oxygen standards. In order to investigate the relationship between nutrient inputs, primary production, and dissolved oxygen in these waters, more comprehensive modeling frameworks were developed. LIS 3.0, developed for the USEPA Long Island Sound Study Office (HydroQual, 1996), includes a water quality model coupled to a NOAA hydrodynamic (Smaltz, 1994) model. The LIS3.0 water quality model incorporated twenty-four water column state-variables (including two functional phytoplankton groups, dissolved inorganic nutrients (nitrogen, phosphorus, and silica), labile and refractory forms of particulate and dissolved organic matter (nitrogen, phosphorus, and carbon), biogenic silica, and dissolved oxygen) and a sediment nutrient diagenesis/flux model developed for the USEPA Chesapeake Bay model (DiToro and Fitzpatrick, 1993). The model was calibrated against an extensive field monitoring data set and used to conduct a nitrogen TMDL, in order to achieve dissolved oxygen standards for the Sound (NYSDEC and CTDEP, 2000). The LIS 3.0 model has also been used to evaluate the benefits of alternative nutrient management scenarios, e.g., wasteload relocation (St.John, 1991) and an East River tidal barrier (St. John, 1994), for the Sound. Monitoring and hydrodynamic/water quality model development for the Jamaica Bay Eutrophication Study were also undertaken. The modeling framework employed for Jamaica Bay was similar in nature to the LIS 3.0 model, but extended the water column and sediment nutrient flux sub-models to include the benthic suspension and deposit feeder communities. The resulting model, the Jamaica Bay Eutrophication Model or JEM (HydroQual, 2002), has been used to evaluate nutrient management alternatives for the Bay. Recognizing that New York-New Jersey Harbor’s water quality issues required a regional planning approach, brought about the development of a System-Wide Eutrophication Model (SWEM). This work was initiated in 1994 with the conduct of a year-long water quality monitoring
program. The SWEM domain includes New York/New Jersey Harbor, the New York Bight to the 100 m isobath along the continental shelf break, Long Island Sound, and the adjoining rivers in New York and New Jersey. SWEM employs the same coupled hydrodynamic/water quality framework as did LIS 3.0, and was calibrated to two year-long data sets. SWEM represents major circulation features of the system (Blumberg et al., 1999), as well as the chemical and biological features of the system (HydroQual, 2001; Landeck Miller and St. John, 2005). SWEM has been used to evaluate nutrient management alternatives as part of a long-term nitrogen control plan. SWEM is currently being used to plan for and to potentially develop Harbor nutrient and pathogen TMDLs. SWEM also provides the basis for a modeling tool under development for the Contaminant Assessment and Reduction Program (CARP). The purpose of the CARP model is to understand the fate and transport of toxic contaminants discharged into the estuary. The result of the discharge of toxic contaminants to the Harbor is that the bed sediments and biota of the Harbor are contaminated. Potentially reducing the level of contaminants in bed sediments and biota of the Harbor is an important issue for maintaining the viability of the Port of New York/New Jersey in terms of reducing costs associated with the disposal of dredged material. The CARP model determines through mass balances the consequences of the contaminant loadings, both past and present, on an estuary-wide basis and has predictive capabilities. The CARP model integrates separate hydrodynamic, sediment transport, eutrophication, chemical fate and transport, and bioaccumulation models into one unified modeling system. What is novel about the CARP model is that it mechanistically calculates the organic carbon to which hydrophobic organic and metallic contaminants complex and also mechanistically calculates rates of mercury methylation and demethylation. Upon completion of the development of the CARP model it will be used to plan for and potentially perform toxics TMDLs for the New York/New Jersey Harbor Estuary. Recently, CARP hydrodynamic model calculations have been applied to assist in evaluating what role pesticides, applied in the watershed of Long Island Sound to combat mosquitos potentially carrying West Nile virus, may have played in the decline of lobster populations in Long Island Sound observed during the summer/fall of 1999. Findings of the West Nile related pesticide modeling evaluation are described in Landeck Miller et al. 2005. OUTCOMES Over the past 25-30 years, municipalities around New York/New Jersey Harbor have constructed and/or upgraded their wastewater treatment facilities leading to significant reductions in the quantities of untreated wastewater, pathogens, and BOD entering the harbor. As a result measures of clean water around the harbor have shown improvement. Mathematical modeling has played an important role in assisting the region’s water quality managers in evaluating the effectiveness of various pollutant reduction and control strategies. The spatial resolution and complexities of the models have grown in time from the earlier models developed by O’Connor. Today’s models incorporate the spatial resolution and physical, chemical, and biological detail required to evaluate the complex environmental issues continuing to challenge the New York /New Jersey Habor and other regions. Going forward, we believe future models will do even more to incorporate ecosystem responses.
Please contact Robin Landeck Miller (201-529-5151 ext. 7119 or
[email protected]) for more information on additional applications of numerical models within the New York/New Jersey Harbor estuary or applications of New York/New Jersey Harbor model kinetics to other waterways. REFERENCES Apicella, G., 2001. Urban Runoff, Wetlands and Waterfowl Effects on Water Quality in Alley Creek and Little Neck Bay. TMDL Science Issues Conference, St. Louis, Missouri, March 4-7, 2001. Apicella, G., J. Roswell and H.P. Moutal, 1988. Achieving water quality through CSO control Flushing Bay, New York City. Presented at the 60th Annual New York Water Pollution Control Association Meeting, New York City, January 10-13, 1988. Apicella, G., F.E. Schuepfer, J. Zuccagnino and V. DeSantis, 1996. Water-quality modeling of combined sewer overflow effects on Newtown Creek. Water Environment Research 68(6):1012-1023. Blumberg, A.F., L.A. Khan, and J.P. St. John, 1999. Three-dimensional hydrodynamic model of New York Harbor Region. J. Hydr. Engr. ASCE. 125(8):799-816. Brosnan, T.M. and M.L. O’Shea, 1996a. Long-term improvements in water quality due to sewage abatment in the Lower Hudson River. Estuaries 19(4):890-900. Brosnan, T.M. and M.L. O’Shea, 1996b. Sewage abatement and coliform bacteria trends in the lower Hudson-Raritan Estuary since passage of the Clean Water Act. Water Environment Research 68(1):25-35. DiToro, D.M. and J.J. Fitzpatrick, 1993. Chesapeake Bay sediment flux model. Prepared for the U.S. Army Corps of Engineer Waterways Experiment Station. Vicksburg, MS. Contract Report EL93-2. Mahwah, New Jersey. Franz, D.R., 1982. A historical perspective on molluscs in Lower New York Harbor, with emphasis on oysters. In Ecological stress and the New York Bight: Science and management, ed. G.F. Mayer, pp. 181-198. Esturarine Research Foundation, Columbia, SC. HydroQual, Inc., 1990. New York City Phase II City-wide combined sewer overflow study of Jamaica Bay and 26th Ward Tributaries. Task 4.2.3 Report: Computer Modeling 26th Ward Tributaries. Prepared for NYCDEP under subcontract to O’Brien and Gere Engineers, Inc. Mahwah, NJ. HydroQual, Inc., 1991. Task 4.3 Modeling of loads and Task 4.4 Modeling of water quality Report. Prepared for NYCDEP under subcontract to Hazen and Sawyer PC Engineers. Mahwah, NJ. HydroQual, Inc., 1996. Water quality modeling analysis of hypoxia in Long Island Sound using LIS 3.0. Prepared for the Management Committee of the Long Island Sound Estuary Study and the New England Interstate Water Pollution Control Commission. Mahwah, New Jersey. HydroQual, Inc. 2001. System-Wide Eutrophication Model (SWEM). Task 10.0 Report. Prepared for the NYCDEP under subcontract to Greeley and Hansen. Mahwah, NJ. HydroQual, Inc., 2002. A water quality model for Jamaica Bay: Calibration of the Jamaica Bay Eutrophication Model (JEM). Prepared for the NYCDEP under subcontract to O’Brien and Gere Engineers, Inc. Mahwah, NJ. Landeck Miller, R.E. and J.P. St. John. 2005. Modeling Production in the Lower Hudson River Estuary. In: J. Levinton, editor. The Hudson River Ecosystem. New York: Cambridge University Press. In Press. Landeck Miller, R.E., J.R. Wands, K.N. Chytalo, and R.A. D’Amico. 2005. Application of Water Quality Modeling Technology to Investigate the Mortality of Lobsters (Homarus Americanus)
in Western Long Island Sound during the Summer of 1999. J. Shellfish Res. 24(3): 859-864. McHugh, J.L., R.R. Young, and W.M. Wise, 1990. Historical trends in the abundance and distribution of living marine resources in the system. In Cleaning up our coastal waters: An unfinished agenda, ed. K. Bricke and R.V. Thomann, pp.1-5-131. Presented at the March 12-14, 1990 regional conference co-sponsored by Manhattan College and the Management Conferences for the Long Island Sound Study, The New York-New Jersey Harbor Estuary Program, and the New York Bight Restoration Plan. New York City Department of Environmental Protection, 2002. 2001 New York Harbor water quality report. NYCDEP, Bureau of Wastewater Pollution Control, Marine Sciences Section, Wards Island, NY. New York State Department of Environmental Conservation (NYSDEC) and Connecticut Department of Environmental Protection (CTDEP), 2000. A total maximum daily load analysis to achieve water quality standards for dissolved oxygen in Long Island Sound. NYSDEC, Albany, NY. CTDEP, Hartford CN. O’Connor, D.J., 1962. Organic Pollution of New York Harbor - Theoretical Considerations. Journal WPCF, 34(9):905-919. O’Connor, D.J., 1966. An analysis of the dissolved oxygen distribution in the East River. Journal WPCF, 38(11): 1813-1830. O’Connor, D.J. and J.L. Mancini, 1972. Water quality analysis of the New York Harbor complex. Journal WPCF, 44(11): 2129-2139. O’Connor, D.J. and J.A. Mueller, 1984. Water quality analysis of the New York Harbor complex. Jour. Environ. Engr. Div., ASCE, 110(6): 1027-1047. Smaltz, R.A., 1994. Application and documentation of the Long Island Sound three-dimensional circulation model. Summary report, Volume 1, Long Island Sound Oceanography Report. NOAA Technical Report NOS OES 003. 77pp. St. John, J.P., 1991. Preliminary assessment of relocation of outfalls from selected sewage treatment plants to alleviate hypoxia in western Long Island Sound. Workshop on Assessment of Alternatives to biological nutrient removal. Marine Sciences Research Center, SUNY. Stony Brook, NY. November, 1991. St. John, J.P., 1994. Hydrodynamic and water quality impacts of the proposed East River tidal barrage. The East River Tidal Barrage. Annals of the New York Academy of Sciences. 742: Suszkowski, D.J., 1990. Conditions in the New York/New Jersey harbor estuary. In Cleaning up our coastal waters: An unfinished agenda, ed. K. Bricke and R.V. Thomann, pp.1-5-131. Presented at the March 12-14, 1990 regional conference co-sponsored by Manhattan College and the Management Conferences for the Long Island Sound Study, The New York-New Jersey Harbor Estuary Program, and the New York Bight Restoration Plan.
