Priorities and Outlook for the Future

Priorities for the future of wastewater management in the Hudson River Estuary include the need for continued investment in WTP maintenance and upgrades, the need to further abate remaining sources of untreated sewage, and the need to investigate if nutrient removal should be required to reduce eutrophication. These are discussed briefly below.

WTP maintenance and upgrades. A continued Federal, state, and local commitment to provide the necessary capital and operations and maintenance investments for municipal wastewater facilities is critical to maintain the dramatic improvements in water quality that have been achieved since the 1972 CWA. At a minimum, aging sewer mains and pumping stations will need to be maintained and replaced to reduce leaks and bypasses. Projected population increases are another significant concern. New York metropolitan area population is projected to increase by 12 percent by 2020 (New York Metropolitan Transportation Council, 1999).

Abatement of remaining sources of untreated sewage.

Although CSOs are not a significant contributor to TSS, BOD5 and nutrients, they are the dominant source of coliform bacteria and floatables. Control of CSO discharges is expensive and difficult. However, some improvements can be achieved for a relatively modest investment. New York City's implementation of EPA's common sense "Nine Minimum Controls" for minimizing CSO discharges has reduced unintentional bypasses by 96 percent, abated 9,500 m3 d-1 of illegal discharges, improved capture of CSOs from 18 percent in 1989 to 44 percent in 1998, increased the capture of floatables from 18-68 percent, and reduced coliform concentrations in the harbor by 50 percent (NYCDEP, 1999). Aggressive implementation of the Nine Minimum Controls by all communities in the estuary would likely achieve further improvements. Untreated discharges from boats can also be locally significant sources of coliforms. New York State's recent efforts to have theU.S. EPA declare the Hudson River a "No Discharge Area," which would prohibit all sewage discharge from vessels from Troy to the Battery, could provide further local improvements (Pataki, 2000).

Nutrients. Wastewater treatment plants (WTPs) are a significant source of nitrogen and phosphorus to the estuary. RecentNationalAcademyreports have listed eutrophication as perhaps the biggest problem in the coastal zone of the United States (NAS, 1993), as one of the greatest research needs for coastal ecology (NAS, 1994), and as one of the two biggest threats to biodiversity in marine ecosystems (NAS, 1996). In order to evaluate the need for nutrient removal, the impact of WTP nutrient loading to the Hudson-Raritan estuary on eutroph-ication and depressed bottom water dissolved oxygen levels in outer areas of New York Harbor, including western Long Island Sound, Raritan Bay, Jamaica Bay, and the nearshore New Jersey coast is currently being investigated using state-of-the-art hydrodynamic and water quality models (O'Shea and Brosnan, 2000).

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