Development of Reconstructed Streamflows at Stream Gaging Stations and Ungaged Sites in the Passaic and Hackensack River Basins , Water years 1922-2007, Phase 1
New Jersey WSC Archived Projects
Since 1922, there have been significant human related changes in the Passaic and Hackensack River Basins including significant hydrologic modifications as a result of water supply development and land use changes that impact the runoff characteristics of these watersheds. Since the goal of the NJDEP modeling effort is to determine the safe yield of the major water supply systems under present day hydrologic conditions, one of the inputs to the model is reconstructed or natural flows at specified model control points for the period being modeled.
START DATE: 02-JUN-2008
END DATE: 30-NOV-2011
PROJECT NUMBER: LJ00DEE
STUDY OBJECTIVES:
The project will be conducted in two phases with the overall objective to develop reconstructed flows for the Passaic and Hackensack River Basins for water years 1922 through 2007 and provide the data along with a database of all data used in the project to the NJDEP to be used to develop a water supply model for these watersheds. The objective of the first phase is to identify the control points for the model and determine the methodology to reconstruct flows for each control point.
STATEMENT OF PROBLEM:
As discussed above, since 1922, there have been significant human related changes in the Passaic and Hackensack River Basins including significant hydrologic modifications as a result of water supply development and land use changes that impact the runoff characteristics of these watersheds. Since the goal of the NJDEP modeling effort is to determine the safe yield of the major water supply systems under present day hydrologic conditions, one of the inputs to the model is reconstructed or natural flows at specified model control points for the period being modeled. The purpose of reconstructing flows is to remove past human impacts on streamflow and develop flows that reflect as close as possible what the streamflow would have been without human influences. The reconstructed streamflows are sometime referred to as natural streamflow but in most cases, all human impacts cannot be accounted for and the reconstructed flow is only an estimate of natural flows. With present day water demands, reservoir operations, wastewater treatment discharges used as another input to the model with the reconstructed flows, the impact of past droughts on water supply systems can be simulated under present day conditions to establish system safe yields within the limitations of the model.
STRATEGY AND APPROACH:
Review period of record of stream gages listed above that would represent “natural” flow conditions.
- Review results of USGS report ( in final review) “Ecological- Relevant Hydrologic Indices for a Baseline Period of record for Selected Streamflow Gaging Stations in New Jersey”
- Trend analysis – perform trend analysis on annual flow, three low flow and three high flow regimes for the period of record and for different time periods (i.e. 1922 – 1940, 1922 – 1960, 1970 – 2007, and seasonal).
- Determine gages and control points where flows do and do not have to be reconstructed.
- Determine if periods that are available for pumping and the amount of water available has changed since the 1960s drought.
DISCLAIMER: This webpage contains information about completed or inactive projects from the NJ Water Science Center. It has been created for historical purposes and may be a utility to locate published information. This page should not be considered an authoritative source. You are encouraged to contact the NJ WSC for more current information.
Below are publications associated with this project.
Methods used to reconstruct historical daily streamflows in northern New Jersey and southeastern New York, water years 1922–2010
Since 1922, there have been significant human related changes in the Passaic and Hackensack River Basins including significant hydrologic modifications as a result of water supply development and land use changes that impact the runoff characteristics of these watersheds. Since the goal of the NJDEP modeling effort is to determine the safe yield of the major water supply systems under present day hydrologic conditions, one of the inputs to the model is reconstructed or natural flows at specified model control points for the period being modeled.
START DATE: 02-JUN-2008
END DATE: 30-NOV-2011
PROJECT NUMBER: LJ00DEE
STUDY OBJECTIVES:
The project will be conducted in two phases with the overall objective to develop reconstructed flows for the Passaic and Hackensack River Basins for water years 1922 through 2007 and provide the data along with a database of all data used in the project to the NJDEP to be used to develop a water supply model for these watersheds. The objective of the first phase is to identify the control points for the model and determine the methodology to reconstruct flows for each control point.
STATEMENT OF PROBLEM:
As discussed above, since 1922, there have been significant human related changes in the Passaic and Hackensack River Basins including significant hydrologic modifications as a result of water supply development and land use changes that impact the runoff characteristics of these watersheds. Since the goal of the NJDEP modeling effort is to determine the safe yield of the major water supply systems under present day hydrologic conditions, one of the inputs to the model is reconstructed or natural flows at specified model control points for the period being modeled. The purpose of reconstructing flows is to remove past human impacts on streamflow and develop flows that reflect as close as possible what the streamflow would have been without human influences. The reconstructed streamflows are sometime referred to as natural streamflow but in most cases, all human impacts cannot be accounted for and the reconstructed flow is only an estimate of natural flows. With present day water demands, reservoir operations, wastewater treatment discharges used as another input to the model with the reconstructed flows, the impact of past droughts on water supply systems can be simulated under present day conditions to establish system safe yields within the limitations of the model.
STRATEGY AND APPROACH:
Review period of record of stream gages listed above that would represent “natural” flow conditions.
- Review results of USGS report ( in final review) “Ecological- Relevant Hydrologic Indices for a Baseline Period of record for Selected Streamflow Gaging Stations in New Jersey”
- Trend analysis – perform trend analysis on annual flow, three low flow and three high flow regimes for the period of record and for different time periods (i.e. 1922 – 1940, 1922 – 1960, 1970 – 2007, and seasonal).
- Determine gages and control points where flows do and do not have to be reconstructed.
- Determine if periods that are available for pumping and the amount of water available has changed since the 1960s drought.
DISCLAIMER: This webpage contains information about completed or inactive projects from the NJ Water Science Center. It has been created for historical purposes and may be a utility to locate published information. This page should not be considered an authoritative source. You are encouraged to contact the NJ WSC for more current information.
Below are publications associated with this project.