In 2011, the U.S. Geological Survey (USGS) in partnership with the New Jersey Department of Environmental Protection began a multidisciplinary research project to better understand the water quality in Barnegat Bay, New Jersey. This back-barrier estuary is flushed by only three inlets and is experiencing degraded water quality, algal blooms, loss of seagrass, and increases in oxygen stress, macro algae, stinging nettles, and brown tide. The scale of the estuary and the scope of the problems within it necessitate a multidisciplinary approach that includes establishing the regional geology, its physical characteristics, and modeling how the estuary's morphology interacts to affect its water quality. Scientists from USGS Coastal and Marine Geology Program offices in Woods Hole, Massachusetts, and St. Petersburg, Florida, began mapping the sea floor of the Barnegat Bay-Little Egg Harbor estuary in November 2011 and completed in September 2013. With funding from the New Jersey Department of Environmental Protection and logistical support from the USGS New Jersey Water Science Center, they collected data with a suite of geophysical tools, including swath bathymetric sonar for measuring sea floor depth, a sidescan sonar for collecting acoustic-backscatter data (which provides information about sea floor texture and sediment type), subbottom profiler for imaging sediment layers beneath the floor of the estuary, and sediment samples with bottom photographs for ground validation of the acoustic data. More information about the individual surveys conducted as part of the Barnegat Bay Project can be found on the Woods Hole Coastal and Marine Science Center Field activity webpages: 2011-041-FA: http://woodshole.er.usgs.gov/operations/ia/public_ds_info.php?fa=2011-041-FA 2012-003-FA: http://woodshole.er.usgs.gov/operations/ia/public_ds_info.php?fa=2012-003-FA 2013-014-FA: http://woodshole.er.usgs.gov/operations/ia/public_ds_info.php?fa=2013-014-FA 2013-030-FA: http://woodshole.er.usgs.gov/operations/ia/public_ds_info.php?fa=2013-030-FA