Geology topics

Jerilyn V. Collenburg

Publications and source records attributed to Jerilyn V. Collenburg.

4 recordsLinked to original sources

USGS2025

Statistical streamflow comparison of current and historical 30-year periods for selected streams in New Jersey

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.

New Jersey↗

USGS2025

Time of travel of releases from Lake Wallenpaupack to the U.S. Geological Survey’s streamgage monitoring location on the Delaware River at Montague, New Jersey

In 2016, the U.S. Geological Survey (USGS) carried out a hydraulic study within the upper Delaware River Basin for the purpose of determining the time of travel for water releases from the Brookfield Renewable U.S. hydroelectric plant at Lake Wallenpaupack, Pennsylvania, to reach the USGS streamgage located on the Delaware River at Montague, New Jersey (site number 01438500). From September 19 to October 14, 2016, Brookfield Renewable initiated repeated releases of approximately 650 cubic feet per second (ft 3 /s) and 1,440 ft 3 /s. Hydraulic signals from the releases were tracked at nine key locations between Lake Wallenpaupack and the USGS streamgage at Montague, New Jersey (01438500). Gage height data were recorded at streamgages at major confluences of the Lackawaxen and Delaware Rivers, Mongaup and Delaware Rivers, and the Neversink and Delaware Rivers. The time of travel to the USGS streamgage at Montague, New Jersey, was determined to be 1,185 minutes during the approximately 650 ft 3 /s releases and 960 minutes during the approximately 1,440 ft 3 /s releases. Elevated streamflow between Lake Wallenpaupack and the Montague streamgage from runoff events prior to the dam releases was found to decrease calculated time of travel identified during the study. The results from this study can be used as a guide to estimate time of travel while considering the water level of downstream streamflow, the volume of water being released, and other outside influences, such as precipitation and snowmelt.

New Jersey, New York, Pennsylvania↗

USGS2020

Bathymetry of Morris Lake (Newton Reservoir), New Jersey, 2018

Morris Lake, also known as Newton Reservoir, has been the source of drinking water for the Town of Newton, New Jersey, since the early 1900s. Although Morris Lake has been used as a source of drinking water for many years, its capacity was previously uncertain. In April 2018, the U.S. Geological Survey and the New Jersey Department of Environmental Protection conducted a bathymetric survey of Morris Lake using a multibeam echosounder to map the reservoir. The points measured with the multibeam echosounder were combined with light detection and ranging data above the water surface and processed to create a 3.3-foot (1 meter) raster grid of the bathymetric surface, bathymetric contours at 2-foot intervals of depth and elevation, and an elevation-area-capacity table. The results of the bathymetric survey show that Morris Lake has a maximum depth of just over 119 feet with an average depth of 42 feet. Like the surrounding topography, parts of the reservoir are extremely steep. The capacity of the reservoir at full spillway level is 1,980 million gallons, with a corresponding surface area of 145 acres. The accuracy of the mapped multibeam echosounder bathymetric data was evaluated using a quality assurance dataset collected with a single-beam echosounder; 9,386 quality assurance points were spatially joined with the mapped raster surface to compute measurement errors. The calculated median point error for Morris Lake was 0.23 foot, the median absolute error was 0.35 foot, and the 95-percent accuracy was 2.68 feet. The largest errors occurred in the steepest areas of the reservoir and in unmeasured areas. Geospatial files of the bathymetry data, including the mapped bathymetric surface, contours, and capacity tables, quality assurance points, and associated metadata are available for download as part of an accompanying U.S. Geological Survey data release.

New Jersey↗

USGS2013

Hurricane Irene and associated floods of August 27-30, 2011, in New Jersey

Intense rainfall from Hurricane Irene during August 27–30, 2011, inundated streams throughout New Jersey resulting in peak streamflows exceeding the 100-year recurrence interval at many streamgages and causing heavy property and road damage. The rain event affected the entire State. Some notably affected areas were the Passaic and Hackensack River Basins in northeastern New Jersey with new peaks of record at 10 continuous-record streamflow-gaging stations on streams such as the Hackensack River, Ramapo River, Rockaway River, and Green Pond Brook. In the Atlantic Coastal Basin, new peaks of record were recorded at 6 continuous-record streamflow-gaging stations, 2 of which were on the Manasquan River, 1 on Toms River, 1 on the Mullica River, 1 on the North Branch Metedeconk River, and 1 on the West Branch Wading River. Several tributaries to the Delaware River, such as the Pequest River, Flat Brook, and Assunpink Creek, also experienced major flooding with new peaks of record at nine continuous-record streamflow-gaging stations. The U.S. Geological Survey (USGS) documented peak streamflows and water-surface elevations at 125 continuous-record streamflow-gaging stations, 27 crest-stage partial-record stations, and peak water-surface elevations at 24 continuous-record tide gages within the State of New Jersey. With rainfall totals averaging more than 10 inches throughout the State, peak-of-record flood elevations and streamflows occurred at 32 continuous-record streamflow-gaging stations. Flood-frequency recurrence-intervals were recomputed for 80 gages with 20 or more years of record; 25 crest-stage gages ranged from 25 years to greater than 500 years for the peak-of-record floods. The maximum peak streamflow per square mile ranged from 20 to 759 cubic feet per second per square mile. The August 27–30, 2011, flood peaks rank as the peaks of record for 32 continuous-record streamflow-gaging stations with a period of record of 23 to 100 years, as the second highest peaks for 21 continuous-record streamflow-gaging stations with a period of record of 21 to 114 years, and the third highest peaks of record for 11 continuous-record streamflow-gaging stations with a period of record of 43 to 96 years. Several gages have documented peaks dating back to 1903. About 1 million people across the State were evacuated, and every county was eventually declared a Federal disaster area. Property damage in New Jersey was estimated to be $1 billion. Governor Chris Christie declared a State of Emergency for New Jersey on August 31, 2011. After assessment of the damage by the Federal Emergency Management Agency, President Obama declared all 21 counties major disaster areas in the State of New Jersey on August 31, 2011.

New Jersey↗