Skip to main content


Robert S Regan


Office of the Chief Operating Officer

Office Phone: 303-236-5008
ORCID: 0000-0003-4803-8596

Supervisor: Gregory J McCabe
The files contained on this site are for use with the National Hydrologic Model (NHM) for the Precipitation Runoff Modeling System (PRMS), developed by the Modeling of Watershed Systems (MoWS) group of the U.S. Geological Survey. PRMS is a daily deterministic watershed-scale model (Markstrom and others, 2015), and can be used at a conterminous United States (CONUS) extent with on the Geospatial Fabric (Viger and Bock, 2014) in the NHM infrastructure (Regan and others, 2018). The NHM-PRMS is the sum of three parts: the source code, parameter values, geospatial fabric (Regan and others, in press). These components are used to generate the simlation output files. Child items of this page include all or parts of these...
Model Name (Name of the model, including acronyms): Coupled Ground-Water and Surface-Water Flow Model Based on the Integration of the Precipitation-Runoff Modeling System (PRMS) and the Modular Ground-Water Flow Model (MODFLOW-2005) (GSFLOW) Contact Name(s) (Person(s) responsible for maintenance of the model): Richard Niswonger, Andrew T Leaf Contact Email(s):, Originator(s) (Name(s) of the model developer(s)/author(s)): Richard Niswonger, Robert S Regan Model Version (Version of the model, (i.e., 2.0)): 2.1.0 Online Link (An organizational website or repository, if available. Multiple allowed):
Modeling of watershed response to normal and extreme climatic conditions or to changes in the physical conditions of a watershed requires the simulation of a variety of complex hydrologic processes and process interactions. Some of these processes are well understood at a point or for a small area; others are poorly understood at all scales. Increasing spatial and temporal variability in climate and watershed characteristics with an increase in watershed area adds significantly to the degree of difficulty in investigating and understanding these processes. Research is needed to better define these processes and to develop techniques to simulate these processes and their interactions at all watershed scales. Project...
Abstract: A study was conducted by the U.S. Geological Survey (USGS), in cooperation with the Gulf Coastal Plains and Ozarks Landscape Conservation Cooperative (GCPO LCC) and the Department of the Interior Southeast Climate Adaptation Science Center, to evaluate the hydrologic response of a daily time step hydrologic model to historical observations and projections of potential climate and land-cover change for the period 1952–2099. The model simulations were used to compute the potential changes in hydrologic response and streamflow statistics across the Southeastern United States, using historical observations of climate and streamflow. Thirteen downscaled general circulation models with four representative concentration...
Categories: Publication; Types: Citation
Model Name (Name of the model, including acronyms): Precipitation-Runoff Modeling System (PRMS) Contact Name(s) (Person(s) responsible for maintenance of the model): Steven L Markstrom, Robert S Regan Contact Email(s):, Model Version (Version of the model, (i.e., 2.0)): 5.1.0 Online Link (An organizational website or repository, if available. Multiple allowed): Abstract (Description or summary of the model, including its purpose or goals and the type or formalism of the model (e.g., system dynamic, agent based model, machine learning), preferably accompanied by relevant keywords): "Modeling framework capable...
ScienceBase brings together the best information it can find about USGS researchers and offices to show connections to publications, projects, and data. We are still working to improve this process and information is by no means complete. If you don't see everything you know is associated with you, a colleague, or your office, please be patient while we work to connect the dots. Feel free to contact