Geology topics
Source-linked reports with geographic coverage including New Jersey.
Using 3D Elevation Program data, a modern illustration of each State's landscape showcases its elevation differences in vivid detail. Each State has been consistently adjusted and colorized according to its highest and lowest elevations, accentuating differences even in States with low relief. To further emphasize landforms, shaded relief has been added on top of the elevation colors.
Anthropogenic actions have directly and indirectly modulated salt marsh extent globally. For example, direct actions such as draining and filling of marshes for agriculture were common before the early 20th century, while development on barrier islands has indirectly reduced the capacity of back-barrier marshes to evolve in response to coastal processes. Similarly, restoration efforts span a spectrum between direct actions such as hydrologic reconnection and sediment placement to indirect actions such as shoreline protection and facilitation of upland migration. With a combination of remote sensing and synoptic in-situ observations, we demonstrate that the vegetative establishment of two disparate salt marsh complexes are strongly linked to their access to external sediment supply, position in the coastal landscape, and anthropogenic history. A marsh complex fringing Delaware Bay, in a former agricultural reclamation area, was directly modified through re-introduction of tidal forcing; vegetative establishment occurred rapidly (3% y −1 increase in vegetative cover) due to a high flood-ebb suspended sediment differential (+32 mg l −1 ), indicating sediment import. The other marsh complex, behind a sand spit fronting the Atlantic Ocean, vegetated indirectly in response to updrift beach nourishment which provided a sheltered environment for expansion. The lower suspended sediment differential (+1.3 mg l −1 ) led to a slower vegetation establishment rate (1.7% y −1 ). The directly modified and restored complex responded more rapidly than the indirectly modified and restored complex due to sediment availability. Direct restoration may be more rapid than indirect methods, and reversing anthropogenic impacts is possible on relatively short timescales, if sufficient external sediment supply exists. Siting of restoration projects can therefore leverage external forcing to accelerate recovery and enhance resilience. In light of ongoing coastal transgression, these examples also demonstrate a potential difference in return-on-restoration-investment between back-barrier marshes undergoing coastal squeeze and estuarine fringing marshes that are naturally transgressing across the coastal landscape.
As the population of New Jersey continues to remain dense, the need for water supply will likely continue to be high, which can lead to water managers needing to make difficult decisions about managing drinking-water supply. Streamgaging weirs like the ones used by the U.S. Geological Survey (USGS) play a critical role in providing accurate and stable streamflow data, but their presence can affect the passage of diadromous fish species such as river herring ( Alosa pseudoharengus [alewife], Alosa aestivalis [blueback herring], and Alosa sapidissima [American shad]). In some situations, weirs existing in rivers and streams are no longer used because they were part of a farm irrigation system or some type of industrial operation. The weir at the USGS streamgage 01402000 Millstone River at Blackwells Mills, New Jersey, was purposefully built as a hydraulic-control structure that provides a precise and stable control for the measurement of stage and computation of continuous streamflow. To satisfy the dual need of maintaining accurate streamflow data and providing improved fish passage for select species of fish during migration season, the USGS proposed the development and evaluation of two alternative weir designs that would meet the criteria established for successful passage of American shad, alewife, and blueback herring during their yearly migration. The designs were also required to maintain adequate control of the upstream pool elevation necessary for the precise computation of streamflow used by State agencies for municipal water-supply purposes for surrounding communities. Two alternative weir design modifications were incorporated at the center of the Blackwells Mills weir and modeled using two-dimensional hydraulic modeling software and three-dimensional computational fluid-dynamics software to simultaneously evaluate conditions for passage of the target fish species and effects to streamflow computations at the streamgage. The models were calibrated to existing conditions around the weir location using surveyed-elevation data and recorded stage, streamflow, and velocity in the Millstone River. The alternative weir designs lowered the weir crest by 1.02 feet (ft) and the resulting simulations showed an effective increase in depth of 0.98 ft at the median streamflow of 251 cubic feet per second (ft 3 /s) and 0.96 ft at the 95-percent exceedance streamflow of 98 ft 3 /s. The alternative weir designs were also found to increase streamflow depth across the shallowest portions of the weir structure at the downstream anti-scour skirt by lowering the skirt about 4 inches, allowing for two or more body depths of water for American shad, alewife, and blueback herring at the median migration streamflow of 251 ft 3 /s. The alternative weir designs also reduced the highest stream velocities across the downstream weir sill and anti-scour skirt from about 9 to 10 feet per second, and the depth-averaged velocity to about 7 to 8 feet per second. The sensitivity of the weir with respect to the computation of streamflow was increased from about 1.8 cubic feet per second per hundredth foot to 1.6 cubic feet per second per hundredth foot for streamflows of about 10–100 cubic feet per second.
Harmful algal blooms, particularly cyanobacteria harmful algal blooms (cyanoHABs), have emerged as a substantial global concern because of their detrimental effects on water quality and aquatic ecosystem health. CyanoHABs can produce cyanotoxins, which pose serious health risks to humans and wildlife, such as liver failure and respiratory distress. This is particularly concerning for water bodies that serve as drinking-water sources. Recent trends indicate an increase in the frequency and intensity of cyanoHABs globally. This study focuses on the Raritan Basin Water Supply Complex in New Jersey, where extensive monitoring was conducted from August 2020 to August 2021 to assess the presence of cyanobacteria and associated cyanotoxins. The research utilized a combination of discrete water-quality sampling, continuous monitoring, and solid phase adsorption toxin tracking (SPATT) to capture the dynamics of cyanotoxin occurrence and potential transport. Findings revealed a widespread presence of cyanobacteria and potential for cyanotoxin production, although actual cyanotoxin concentrations remained below drinking water and recreational thresholds. The study, conducted by the U.S. Geological Survey (USGS) in collaboration with the New Jersey Water Supply Authority (NJWSA) and the New Jersey Department of Environmental Protection (NJDEP), highlighted the limitations of traditional sampling methods and emphasized that continuous monitoring can support better understanding of how cyanoHAB conditions change over time and in different places. Genetic testing included quantitative polymerase chain reaction (qPCR) analyses, which demonstrated higher sensitivity, or increased findings of cyanobacteria compared to microscopy, indicating the potential for use in early warning systems. This research underscores that integrating various detection methods and hydrological data can enhance understanding of cyanotoxin dynamics in river systems.
The Delaware River basin (DRB) provides drinking water to 15 million people in the surrounding area. Water is frequently withdrawn from the freshwater reaches of streams, above head of tide, in the DRB for use as public drinking water. During extended periods of low flow, saltwater can move upstream, which can threaten drinking-water supplies in the basin. Due to spatial patterns in bathymetry, tidal influences within the DRB, and varying weather conditions, it can be hard to predict the movement and upstream extent of the freshwater-saltwater interface, often defined as the salt-front. Although there is a relationship that predicts this location in the main stem of the Delaware River, there lacks a relationship for its tributaries, such as the Maurice and Cohansey Rivers in southwestern New Jersey. In this study, a relationship was developed between daily specific conductance (SC) at gage locations along the tidal river reaches of the Maurice and Cohansey Rivers to the daily upstream location of the salt-front. The study augmented existing real-time tide gage data with the collection of water temperature and specific conductance data to develop the relationship. Additionally, longitudinal profiles upstream of the selected tide gages were conducted during a range of high tide conditions to define the location of the salt-front. Equations were then developed that related the daily SC measured at the tide gage to the upstream location of the salt-front. The equations were used to estimate the daily upstream location of the salt-front for the period of July 15, 2021, to July 15, 2024. This work can aid in understanding the propagation of saltwater upstream, which can affect local communities and crop farmers along these tidal reaches of the DRB.
Ground-motion simulations of notable earthquakes in the central and eastern United States are limited and typically assume one-dimensional (1D) Earth structure. In this study, we use a three-dimensional (3D) seismic velocity model to better constrain the depth and focal mechanism of the April 5th, 2024, moment magnitude 4.8 Tewksbury earthquake and investigate the spatial variability of earthquake ground motions and the effects of nearby sedimentary basins. We perform earthquake ground-motion simulations up to 0.5 Hz using the 3D spectral-element wave-propagation solver SPECFEM3D over a region 280-km wide by 260-km long by 77-km deep. Topography and subsurface geophysical structure are assigned using the U.S. Geological Survey National Crustal Model with a minimum shear-wave velocity of 200 m/s. We use earthquake time series from 13 broadband seismic stations in the region that have a uniform azimuthal distribution and epicentral distances ranging from 76 to 131 km to compare with synthetics and explore the effects of 1D versus 3D seismic structure on focal mechanism and depth solutions. Ground-motion intensity metrics are also presented relative to the NGA-East ground-motion models (GMMs) currently used in seismic hazard assessments for the region. We find that the 3D model, which reveals a wide spatial variability of period-dependent ground motions, yields better predictions of earthquake ground motions relative to the 1D model and the NGA-East ergodic ground-motion model, with 76 percent reduction of residual variance in observed ground motions averaged over 3-, 5-, 7-, and 10-second periods. Use of the 3D model to solve for a focal mechanism yields a shallower focal depth at 4 km and a shallower east-dipping focal plane relative to the U.S. Geological Survey regional moment tensor and Global Centroid Moment Tensor. Our study demonstrates that use of 3D seismic velocity models can improve estimates of earthquake focal mechanisms, ground motions, and seismic hazard.
Few studies have examined cyanobacteria persistence starting from lacustrine cyanobacteria harmful algal blooms (HABs) downstream. Multiple lakes and reservoirs within New Jersey's Raritan Basin Water Supply Complex (RBWSC) feature recurrent HABs and discharge water into the Raritan River. As the RBWSC provides drinking water to 1.5 million people, these HABs create drinking water treatment and human health concerns. This study quantitatively reviews the persistence of cyanobacteria communities across the RBWSC from cyanobacteria-dominated lacustrine sources to downstream drinking water and qualitatively assess what, if any, water chemistry parameters influenced the persistence, growth, or decline of cyanobacteria during downstream transport. Statistical tests showed there was a lack of continuity between cyanobacteria communities along the Raritan River, except for periods of higher streamflow and higher releases from the Spruce Run Reservoir. Results along the Millstone River suggested the potential for in-river cyanobacteria growth, which overlapped with periods of low streamflow and high nutrient concentrations in the summer and fall. A permutational analysis of variance (PERMANVOA) test found significantly dissimilar ( p < 0.01) cyanobacteria communities between lake and reservoir outlet sites and downstream sites in the Raritan, but not the Millstone River ( p = 0.928). A similarity percentage (SIMPER) analysis found cyanobacteria communities changed from high densities of bloom forming cyanobacteria ( Aphanocapsa, Aphanizomenon, Microcystis) at the lake outlet sites to low densities of non-bloom forming cyanobacteria ( Synechcoccus, Chroococcus) along the Raritan mainstem, with Aphanocapsa the most notable bloom forming genera overlapping between sites. Investigating cyanobacteria on a watershed-specific basis could enhance understanding of the site-specific transport mechanisms and water chemistry parameters that facilitate community persistence.
As the population of New Jersey increases, supplying adequate drinking water to meet demand remains a high priority. To better understand potential streamflow trends over time, the U.S. Geological Survey completed a study comparing low flows at continuous- and partial-record streamgages in New Jersey between a historical period (1950–79) and a current period (1990–2019). Fourteen statistics (one median for each of the twelve monthly minimum 1-day flows, minimum 7-day average streamflow with a 10-year recurrence interval, and median of the daily mean flows for the month of September) were calculated to evaluate how streamflow conditions may differ between the two time periods. Percent change was also calculated to better understand the magnitude of difference between the periods at individual streamgages. A Paired Wilcoxon Signed-Rank Test was implemented to test for a change in distribution between the two time periods for each statistic of interest. Results indicated that the median of the minimum 1-day flows for the months of January, February, June, September, and December and the median of the daily mean flows for the month of September had a statistically significant difference in distribution between the time periods for continuous-record streamgages. None of the statistics had a statistically significant difference in distribution for the partial-record streamgages. The largest percent changes between time periods occurred in the northern part of the state, above the Fall Line. Precipitation, land cover, and water use changes were assessed to contribute to the understanding of these differences between time periods. The median of the minimum 1-day flows for the months of January and December generally increased across the state, whereas the median of the minimum 1-day flows for the months of May and September generally decreased throughout the state.
The U.S. Geological Survey, in cooperation with the New Jersey Department of Environmental Protection (NJDEP), prepared potentiometric surface maps for 10 confined aquifers of the New Jersey Coastal Plain physiographic province based on water-level measurements collected during late 2018 and early 2019 from 951 wells in New Jersey and parts of Pennsylvania and Delaware. Maps were prepared for the confined Cohansey aquifer, Rio Grande water-bearing zone, Atlantic City 800-foot sand, Piney Point aquifer, Vincentown aquifer, Wenonah-Mount Laurel aquifer, Englishtown aquifer system, and the upper, middle, and lower aquifers of the Potomac-Raritan-Magothy aquifer system. Potentiometric surface maps indicate regional cones of depression in the following aquifers and the counties in which they are centered: Atlantic City 800-foot sand in Atlantic County, the Piney Point aquifer in Cumberland County, the Wenonah-Mount Laurel aquifer and Englishtown aquifer system in Monmouth and Ocean Counties, the Wenonah-Mount Laurel aquifer in Camden and Gloucester County, the upper aquifer of the Potomac-Raritan-Magothy aquifer system in Ocean County, and the upper, middle, and lower aquifers of the Potomac-Raritan-Magothy aquifer system in Camden County. Cones of depression with smaller areal extents were in the confined Cohansey aquifer, the Rio Grande water-bearing zone, the Atlantic City 800-foot sand centered in Cape May County, the Piney Point aquifer centered in Ocean County, the Wenonah-Mount Laurel aquifer in Salem and Burlington Counties, the Englishtown aquifer system in Camden County, the upper aquifer of the Potomac-Raritan-Magothy aquifer system in Monmouth County, and the middle aquifer of the Potomac-Raritan-Magothy aquifer system in Monmouth, Ocean, and Salem Counties. No cone of depression was interpreted in the Vincentown aquifer. Long-term hydrographs are presented for 75 wells spanning each of the 10 confined aquifers, and contain a mix of discrete water-level measurements and daily mean water levels based on continuously recorded 15-minute data. Changes of water levels during 2014–19, as indicated by the hydrographs, were compared with those of previous periods to assess any departures from historical data. During 2014–19, water levels were stable and fluctuated within similar ranges as previous periods in the following aquifers and locations: all wells in the confined Cohansey aquifer, the Rio Grande water-bearing zone, the Vincentown aquifer, the Englishtown aquifer system, the Piney Point aquifer wells in Burlington and Ocean Counties, six of eight wells in the Wenonah-Mount Laurel aquifer, all wells in the upper and lower aquifers of the Potomac-Raritan-Magothy aquifer system outside NJDEP Critical Areas, and all wells in the middle aquifer of the Potomac-Raritan-Magothy aquifer system except those within NJDEP Critical Area II. Increasing water levels in 2014–19, ongoing since historical periods, were indicated in the following aquifers and locations: Atlantic County wells in the Piney Point aquifer, all wells in the upper and lower aquifers of the Potomac-Raritan-Magothy aquifer system outside NJDEP Critical Areas, and all wells in the middle aquifer of the Potomac-Raritan-Magothy aquifer system within NJDEP Critical Area II. Water levels in the Atlantic City 800-foot sand also increased during 2014–19 in wells in Atlantic County and northern Cape May County closer to the center of the cone of depression in that aquifer, which is a response unique to this period and absent from previous periods. During 2013–19, continued decreasing water levels, ongoing since previous periods, were indicated by hydrographs of Atlantic City 800-foot sand wells in southern Cape May County, Piney Point aquifer wells in Cumberland County where the regional cone of depression is located, and two wells in the Wenonah-Mount Laurel aquifer—070478, which in 2014–19 departed from previous periods, and 330020, which continued a gradual decrease throughout its period of record.
Nervous necrosis virus (NNV) causes a neurologic disease in a wide range of marine fish and poses serious disease risks to marine aquaculture worldwide. Little is known about the presence of NNV along the Atlantic coast of the United States, aside from the presence of barfin flounder nervous necrosis virus (BFNNV) in coldwater species in the northern part of this range. Herein we conducted surveillance for NNV from 2020 to 2022 in the mid-Atlantic region of the United States in black sea bass Centropristis striata , a serranid fish that is found throughout the eastern U.S. coast. Molecular detection methods have identified and characterized red-spotted grouper nervous necrosis virus (RGNNV) sequences at low prevalence throughout the years. Further, in 2022, a higher prevalence of a novel NNV genotype, tentatively named black sea bass nervous necrosis virus (BSBNNV), was characterized for the first time. Though virus isolation was unsuccessful, this study was the first to genetically identify NNV in this region and in this species. These findings highlight the need for further research on NNV to understand epidemiology and virulence in the context of marine fisheries and an emerging marine aquaculture industry in the United States.
Salt marsh resilience to sea-level rise largely depends on the balance of sediment exchanges with surrounding bays. In this study, we investigate mechanisms that determine residual sediment fluxes using continuous measurements of bay-marsh sediment exchange conducted in a tidal creek spanning 13 months (753 tidal cycles) in an intertidal marsh recently subsidized with sediment via thin-layer placement. The maximum water level in each tidal cycle varied over seasonal and fortnightly timescales and was driven by a combination of the seasonal cycle in mean sea level (maximum in September, minimum in January) and the fortnightly spring-neap cycle. Residual water fluxes tended to be ebb-directed during overbank tides, possibly due to water crossing creekshed boundaries in the intertidal zone when water levels were sufficiently high. Sediment concentrations on the ebb of overbank tides exceeded those of their corresponding floods, but only for tidal cycles in which water temperatures exceeded 14°C. The interaction of these dynamics resulted in over 90% of the net sediment export from the creek occurring during overbank tides during warmer months—conditions met in 30% of the observed tidal cycles. These findings exemplify the importance of accounting for seasonality in sediment fluxes when assessing sediment budgets of salt marshes and illustrate how sediment budgets assessed with shorter duration datasets may exhibit seasonal bias. Additionally, they suggest that sediment retention for thin-layer sediment placement projects may be high over the course of the first year after sediment subsidies are deployed.
This report, prepared in cooperation with the New Jersey Department of Environmental Protection, presents a method for estimating daily public supply water use by drinking water service area systems for New Jersey. The ability to accurately estimate daily public supply water use could help water supply planners in New Jersey better understand and manage the state’s limited water resources and balance the competing needs for freshwater resources. Data sources for this work include daily public supply water-use data from 2016 through 2020 acquired from New Jersey American Water for 15 drinking water service areas and monthly data exported from the New Jersey Department of Environmental Protection’s online water transfer data model database (known as NJWaTr). The two datasets were compared by aggregating the daily data to a monthly timescale. Statistical regression analysis was applied to the daily data, along with climate data, to evaluate what factors are influential in estimating daily fluctuations and trends in daily public supply water use. Fifteen regression equations were developed, one for each of the 15 drinking water service area systems for which daily data were acquired. Regression equations for systems that had seasonal patterns performed better than equations for non-seasonal systems. For the test year (2020), the average adjusted coefficient of determination for the linear regression with autoregressive errors model among systems with seasonality was 0.78; the average adjusted coefficient of determination for the linear regression with autoregressive errors model among systems with little or no seasonality was 0.25. The effects of anomalous data in the regression analysis were examined by comparing adjusted coefficient of determination values when the atypical data points were removed versus when they were retained in the analysis. Overall, including the anomalous data did not have a large effect on the results, and thus the data were retained for this study. In addition to developing regression equations, all 589 unique drinking water service area systems in New Jersey were characterized based on socio-economic data and monthly water-use data from NJWaTr. Systems that are located near the New Jersey coast, serve populations larger than 1,970 people, or serve areas that have median property values over $256,250 tended to demonstrate seasonal water-use behaviors. Systems that have mostly urban residential land use tended to show little to no seasonal water-use behaviors. Finally, a method was developed to disaggregate monthly data to a daily timescale and was tested against systems for which daily data were not available. Two regression equation forms were developed to be applied to systems beyond the 15 systems from which the original equations were developed; one equation was developed for use when all drinking water service area systems showed little to no seasonality, and the other equation was developed for use when systems displayed seasonal behavior. To the extent possible, uncertainty and possible sources of error were identified and examined in relation to the regression model equations developed. Additional daily data from these 15 systems (over different years) and daily data from different systems could be used to further evaluate the results of the disaggregation through a comprehensive assessment of error. Further adjustments to the regression equations could be made, ultimately enhancing their accuracy.
The U.S. Geological Survey assessed the Quaternary evolution of Seven Mile Island, New Jersey, to quantify coastal sediment availability, which is crucial for establishing sediment budgets, understanding sediment dispersal, and managing coastlines. This report presents preliminary interpretations of seismic profiles, maps of Holocene sand thickness from the shoreline to 2 kilometers offshore, and tables quantifying the volume of available sediment along the coastal margin based on data collected during 2021 and 2022. The results reveal spatial variability in the thickness and cross-shore extent of Holocene sand. The study area was separated into northern, central, and southern zones by using underlying stratigraphy and geomorphic features. The characteristics and spatial extent of the Holocene sand deposit indicate that hydrodynamic processes contribute to its spatial variability. Northern Seven Mile Island contains the thickest deposits of Holocene sand that were formed by sediment bypass around the Townsends Inlet ebb-tidal delta. Specifically, swash bars have welded to the updrift end of Seven Mile Island and have formed thick deposits of Holocene sand that thicken landward and taper seaward. Despite their thickness, these deposits have the smallest cross-shore extent; therefore, northern Seven Mile Island has the smallest volume of Holocene sand of the three geomorphic zones. Central Seven Mile Island has the thinnest Holocene sand deposits because this section of the barrier island is outside the influence of ebb-tidal deltas. Southern Seven Mile Island has the greatest volumes of Holocene sand because of increased accommodation and deposition adjacent to the Hereford Inlet ebb-tidal delta. Even though tidal inlets exert variable influence on the three geomorphic zones, sediment is distributed fairly uniformly within each geomorphic zone; each of the three zones contains 31.05–36.48 percent of the volume of available Holocene sand.
Maintaining streamflow to support human water needs and ecosystem services requires a fundamental understanding of the relations between changes in streamflow processes and ecosystem responses. Changes in the natural patterns in flow, geology, and topography alter the habitats that aquatic organisms rely on for food, shelter, and reproduction. The U.S. Geological Survey (USGS) implemented an ecological-flow framework that encapsulates the basic principles of the Ecological Limits of Hydrologic Alteration (ELOHA) to compare the relations between hydrologic metrics and stream conditions and estimate ecological flow needs in the Barnegat Bay-Little Egg Harbor watershed. As a first step in the ELOHA process, streamflow from two historical time periods (occurring between 1933 and 1988) was compared to streamflow for a recent time period (from 2004-2020) for four major streams in the Barnegat Bay-Little Egg Harbor watershed (North Branch Metedeconk River, Toms River, Cedar Creek, and Westecunk Creek), to evaluate if there were statistically significant differences in streamflow metrics. Analysis of monthly, seasonal, and annual low-flow metrics; patterns in the streamflow record; and general land-use changes were used to develop a better understanding of flow conditions in the watershed. The comparative streamflow analysis indicated that notable changes in flow processes for the study streams occurred between the three periods of record (PORs) evaluated in this study: period of record 1 (POR1, from water years 1933–1958), period of record 2 (POR2, from water years 1974–1988), and period of record 3 (POR3, from water years 2004–2020). For example, the mean of the daily streamflow decreased between the historical POR to the current POR in Cedar Creek but increased in North Branch Metedeconk and Toms Rivers. Larger and more significant changes (p-value <0.10) occurred during specific months or were related to the variability or seasonality of flow. North Branch Metedeconk River and Toms River, the two northern and most developed sites, exhibited changes in low-flow metrics and decreases in minimum n-day moving averages. Decreases in the normalized 75th-percentile exceedance flows were evident at three of the four study sub-basins during POR2 and POR3. In comparison, there was little to no evidence of negative changes to low-flow metrics at Westecunk Creek, the southernmost and least developed site, where all low-flow duration metrics increased as well as seasonal minimum consecutive 7-day average flows. Significant increases in monthly minimums (p-value <0.05) at Cedar Creek for spring months (April, May, and June) also were observed. Natural and anthropogenic processes can alter the landscape resulting in concomitant changes in the streamflow regime. There is a need to assess these changes and synthesize the results into a scientifically defensible set of goals and standards that help support the management of environmental flows. This study represents the initial steps in building the hydrologic foundation to inform management and develop future ecological flow targets that balance water availability for human and ecosystem needs in the Barnegat Bay-Little Egg Harbor watershed.
A coupled three-dimensional hydrodynamic water-quality model has been applied to Barnegat Bay-Little Egg Harbor Estuary, a shallow, back-barrier lagoon located along the central New Jersey coastline. The study aims to enhance understanding of phytoplankton dynamics and nutrient cycling and to quantify estuarine response to potential nutrient load management strategies. The model was calibrated with data from Spring and Summer of 2012 and adequately reproduced spatiotemporal water-quality variability, distribution patterns, trends, and gradients throughout the system. The calibrated model was used to run scenarios for evaluating estuarine response to various nitrogen load reduction intensities. Model results show that geographically focused, variable nitrogen reductions can mitigate the effects of eutrophication and promote improvements in water quality. This study illustrates the role of modeling in developing informed management strategies, highlights complex, nonlinear responses of estuarine environments to anthropogenic influences, and demonstrates how models can be used to develop adaptive, location-specific nutrient management practices.
High resolution topobathymetric field surveys were conducted by the U.S. Geological Survey in collaboration with Northeastern University and in cooperation with the U.S. Fish and Wildlife Service and The Nature Conservancy in a selected shoreline along Gandys Beach, New Jersey, from January to April 2018. These data are a critical model input for hydrodynamic and wave models and can affect the accuracy of model outputs such as wave height, water surface elevation, current velocity, and sediment transport. Gandys Beach is a living shoreline where constructed oyster reefs (CORs) were built to protect the shoreline and enhance habitat for oyster and other species. Because of the complex topography and bathymetry of the study area, higher spatial resolution topobathymetric data are required to resolve the vertical variations near the CORs. During the field survey, the global navigation satellite system positioning method was used to establish the elevation of a benchmark referenced to the North American Vertical Datum of 1988. The topobathymetric data were collected using a total station. Horizontal accuracy of plus or minus 0.05 foot (ft) and vertical accuracy of plus or minus 0.10 ft were calculated using root mean square error between duplicate surveys. Two existing datasets were integrated with the survey data to create an updated topobathymetric dataset for model input and analysis: (1) the U.S. Geological Survey Coastal National Elevation Database 1-meter resolution data developed after Hurricane Sandy and (2) The Nature Conservancy 2017 elevation monitoring data at 10-meter resolution. A root mean square error analysis comparing survey data with the new topobathymetric dataset versus the survey data compared to the original Coastal National Elevation Data dataset showed errors of 0.31 and 2.61 ft, respectively. This improved dataset can be used for wave and hydrodynamic modeling in support of the effectiveness assessment of the CORs and living shoreline restoration along Gandys Beach.
As New Jersey’s population density remains high, so does its requirements for water management. Understanding the streamflow conditions throughout the state and how they may have changed over time is an important part of managing the water resources within the state. The New Jersey Department of Environmental Protection has many responsibilities related to protecting the environment and natural resources and among them is protecting the waters in the lakes, rivers, and streams of New Jersey for current and future use. To support this mission, the U.S. Geological Survey updated high- and low-streamflow statistics for 97 continuous-record streamgages and low-streamflow statistics for 719 partial-record streamgages throughout the state. The continuous-record streamgages included in the study had a minimum of 20 years of record, spanning from 1903 to 2017. This study is an update to previous studies that documented the high- and low-streamflow statistics for New Jersey streams in the 1970s and in 2005. The 1982 report by Gillespie and Schopp documented low-flow characteristics and flow duration for about 400 continuous and partial-record streamgages. The U.S. Geological Survey computed streamflow statistics including, but not limited to, maximum, minimum, and means for period of record, flow durations, nonexceedance high- and low-flow frequencies, base flow, runoff, peak-to-mean flow ratios, and September median streamflow. Overall, both high and low flows are generally increasing in New Jersey, though the results are not uniform across the State. Streamflow trends and changes to duration and frequency statistics can be influenced by local water use, in addition to climate variables. The resulting computations at some streamgages indicated considerable positive change while others showed considerable negative change. Water managers and regulators can use the data provided here and in the companion data release to assess individual stream reaches and watershed management areas to evaluate the available resources and changes, which may have developed during the periods for which streamflow statistics are available.
On 5 April 2024, 10:23 a.m. local time, a moment magnitude 4.8 earthquake struck Tewksbury Township, New Jersey, about 65 km west of New York City. Millions of people from Virginia to Maine and beyond felt the ground shaking, resulting in the largest number (>180,000) of U.S. Geological Survey (USGS) “Did You Feel It?” reports of any earthquake. A team deployed by the Geotechnical Extreme Events Reconnaissance Association and the National Institute of Standards and Technology documented structural and nonstructural damage, including substantial damage to a historic masonry building in Lebanon, New Jersey. The USGS National Earthquake Information Center reported a focal depth of about 5 km, consistent with a lack of signal in Interferometric Synthetic Aperture Radar data. The focal mechanism solution is strike slip with a substantial thrust component. Neither mechanism’s nodal plane is parallel to the primary northeast trend of geologic discontinuities and mapped faults in the region, including the Ramapo fault. However, many of the relocated aftershocks, for which locations were augmented by temporary seismic deployments, form a cluster that parallels the general northeast trend of the faults. The aftershocks lie near the Tewksbury fault, north of the Ramapo fault.