Observing the Urban Estuary: Review and Prospect W.C. Boicourt, M. Li, N. Nidzieko University of Maryland Center for Environmental Science Horn Point Laboratory, Box 775 Cambridge, MD 21613 boicourt@umces.edu mingli@umces.edu nidzieko@umces.edu A.F Blumberg, N. Georgas Stevens Institute of Technology Civil, Environmental, and Ocean Engineering Department Center for Maritime Systems 711 Hudson Street, Hoboken, NJ, 07030 Alan.Blumberg@stevens.edu ngeorgas@stevens.edu E J. Kelly Maritime Association of the Port of NY/NJ 17 Battery Place Suite 913 New York, NY 10004 themaritimeassoc@erols.com T.G. Updyke Center for Coastal Physical Oceanography Old Dominion University garner@ccpo.odu.ed W.D. Wilson NOAA Chesapeake Bay Office Annapolis, MD doug.wilson@noaa.gov Abstract— Establishing an effective observing system for the urban estuary presents oceanographic and operational challenges beyond those common to the continental shelf and open ocean. Examples are used from the Middle Atlantic Bight estuaries to illustrate that, while emerging technologies are facilitating efforts to establish these systems on a sustainable basis, cooperative efficiencies are likely to be necessary for long-term viability. Models of such cooperation are emerging from IOOS and MARACOOS, helping to encourage a vision of success amidst uncertain forecasts of financial support for the enterprise from traditional sources. Index Terms—Urban estuary, observing systems, circulation, (key words) MOTIVATION The longstanding trend in population growth along the coast has an acute impact on shallow estuaries and adjacent coastal seas. These coastal environments are strongly affected by local influences of freshwater inflow, tides, micro-climate, and both bottom and land topography yet are also subject to global and climatological forcing. The increasingly urbanized environments on land, however, have by and large not grown and been developed with a sustainable coastal future in mind, particularly in the face of rapidly varying oceanic and atmospheric conditions. For example, the concrete and rip-rap hardened shorelines created through urbanization and residential development leave little room for shallow water habitats to migrate inland with sea level rise, and consequently lives and property are more vulnerable to storm surges. Competing demands for the use of waterways have led to conflicts and challenges to the management of its rich resources, forcing regulators to attempt to balance the interests of shipping, fishing, recreation, port security and the collective regional use of these water bodies as extensions of municipal and agricultural sewers. On the ecological side of the scorecard, these land and water use conflicts have led to stressed habitats, an increase in seasonal hypoxia or dead zones [1,2,3] invasive species, and a loss of commercial fishing stocks. The need for tracking conditions in the urban estuary has spurred the development of monitoring, observing, and forecast systems intended to provide critical information ranging from long-term trends in water-quality to short-term forecasts of currents, water level and vessel traffic for safe navigation. In part due to this wide range of uses and information needs, the approach to construct these systems has typically been independent and piecemeal. When the daunting costs of these systems are appreciated, addressing only the immediate specialized need for navigation, water-quality monitoring, or scientific research is an understandable response. This independence has seldom yielded successfully sustainable observing systems. Chief among lessons learned in these attempts are not only the critical level of financial support required, but also the critical level of skilled personnel that must be reached before the reliable delivery of valued information products creates sufficient demand. There is therefore an inherent time lag between establishing this demand and the subsequent political and financial action to support the enterprise. This time lag is further widened by the uncertainty of who should pay for these services, especially when the services are presently being delivered apparently