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UFINCH— A Method for Simulating Unit and Daily Flows in Networks of Channels Described by NHDPlus Using Continuous Flow Data at USGS Streamgages

September 22, 2016

The computer program UFINCH (Unit Flows in Networks of Channels) can be used to simulate unit (15-minute) flows in a network of streams defined within the medium resolution National Hydrography Dataset Plus with value added attributes (NHDPlus, v. 2). Daily measured flows at USGS streamgages can be used to provide a flow boundary at the downstream limit of the network. Streamgages upstream of the boundary streamgage can be used as a basis for comparing and adjusting UFINCH simulated flows. A streamflow data inventory is automatically retrieved for a streamgage selected by use of the graphical user interface. Daily flows are automatically retrieved from a USGS website and interpolated to 15-min unit flows. The unit flows at the boundary streamgage are converted to unit water yields by dividing by the basin drainage area. Then, unit yields are shifted backwards in time based on their expected travel times from catchments to the outlet, and applied to upstream catchments. Average water yields are then multiplied by corresponding catchment areas to produce catchment flows, a process that conserves flows in the basin. Catchment flows are translated downstream through intervening channel segments (flowlines) with travel times based on the lengths and average flow velocities defined in the National Hydrography Dataset with Value-Added Attributes (NHDPlus). Simulated flows on gaged flowlines can be compared with, and systematically adjusted for spatial variability in water yields, to improve the match with measured upstream flows. Simulations using long-term flow records at the outlet can be used to extend unit flows at upstream flowlines, with adjustments derived from overlapping periods of record. Graphical user interfaces and automated GIS and flow-data retrievals provide an intuitive environment for efficient and effective applications. UFINCH can be run in the Matlab programming environment or from compiled code on a computer using the Microsoft Windows operating system.

UFINCH Downloads

  • Zip file for Windows operating system (executable and MATLAB source files,(xyz Kb)
  • Zip file for the Matlab Compile Runtime (MCR) file for Windows 64-bit computers. The MCR file must be installed to run UFINCH (908 Mb). 
  • Instructions for installing the MCR file can be found at
  • NHDPlus zip files for individual two-digit hydrologic units needed for applications.
  • Release History
  • Compilation Notes
  • License and Copyright info

Background Literature

Documentation of UFINCH:

  • Holtschlag, D.J., 2017, UFINCH—A method for simulating unit and daily flows in networks of channels described by NHDPlus using continuous flow data at U.S. Geological Survey streamgages: U.S. Geological Survey Scientific Investigations Report 2016-5074
  • USGS Water Resources Applications Software 

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Publication Year 2016
Title UFINCH— A Method for Simulating Unit and Daily Flows in Networks of Channels Described by NHDPlus Using Continuous Flow Data at USGS Streamgages
Product Type Software Release
Record Source USGS Digital Object Identifier Catalog