The Current Period Streamflow Statistics project is computing low flow statistics for both a historic (1950-1979) and more recent (1990-2019) 30-year period. The computed statistics will provide information about streamflow changes over time and an evaluation of more recent streamflow conditions. The project will also present land-use changes, precipitation patterns, and water use in the associated basins to help users evaluate if changes to these characteristics can be linked to changes in streamflow statistics.
The US Geological Survey in cooperation with the New Jersey Department of Environmental Protection (NJDEP) is conducting a study to compute selected low flow statistics for streamgages with relatively low degrees of streamflow regulation. The study will compute low flow statistics for two 30-year periods (1950-1979 and 1990-2019) to help identify changes over time and to present a snapshot of streamflow conditions using more recent data. The selected streamgages are distributed across the state of New Jersey and had to meet the requirement of having a complete record of data for both periods. The study will also utilize partial record sites to increase the total number of locations across the state with computed statistics. The targeted low flow statistics computed for the selected streamgages and partial-record sites are the monthly 1-day low flow medians, September full-month medians, and annual 7Q10 frequency flows. This study will also present land use data, precipitation patterns, and water use information for the associated basins. Results of the study will help inform the New Jersey Water Supply Plan and managers using the Low-flow Margin method to identify HUC-11 basins where water supply may be limited.
