RAPID

Description
RAPID (Routing Application for Parallel computatIon of Discharge) is a river routing model. Given surface and groundwater inflow to rivers, this model can compute flow and volume of water everywhere in river networks made out of many thousands of reaches. The design of RAPID allows it to be adapted to any river network, if given basic connectivity information. RAPID uses a matrix version of the Muskingum method, and has an automated parameter estimation procedure that allows finding optimal model parameters based on available gage measurements. This model uses the Fortran programming language and can be run on personal computers, as well as on massively-parallel supercomputers, with actual parallel speedup. RAPID has the ability to run and/or optimize model parameters on any subbasin included in its computing domain. If major man-made infrastructures are present on the river network, RAPID allows to easily substitute upstream flow by gage measurements during both computation of river flow and optimization of parameters. Detailed information on RAPID can be found in the related publications.

Development history
Designing, developing and testing RAPID were a large part of my Ph. D. work at the Center for Research in Water Resources at the University of Texas at Austin. The development of this model started in September 2007 as I joined the Center for Geosciences at Ecole des Mines de Paris (Mines Paristech), France for a 6-month visit. RAPID was originally developed as a substitute for the river routing scheme of SIM-France, the operational hydro-meteorological model used by Meteo France (the French weather service). The code has since then been adapted to run on the NHDPlus dataset that provides a "blue line" description of the river networks in the USA. For the current NHDPlus version of RAPID, several land surface models can be used to compute inflow of water to the river network.

Code
Download the RAPID source code.
Download input data from David et al. (2011, JHM). These include NHDPlus river network connectivity, lateral inflow from the land surface (computed with Noah-MP) and gage measurements (from USGS NWIS) for a 4-year run (between 2004-01 and 2007-12) in the San Antonio and Guadalupe River Basins in Texas.
Download output data from David et al. (2011, JHM).
Download input data from David et al. (2011, HP). These include SIM-France river network connectivity, inflow from the land surface (computed with ISBA), bilateral inflow from groundwater (computed with MODCOU) for a 10-year run (between 1995-08-01 and 2005-07-31) in the domain of SIM-France.
Download a script to get NLDAS2 land model data and convert them to RAPID inputs.

Documents
A few slides explaining how RAPID works.
A succinct guide on how to compile and run RAPID, and a detailed guide on how to compile and run RAPID. 
Some information on the data model used in RAPID.
Explanations on the input and output files used in RAPID.
A guide on how to download USGS NWIS observations and format them for use in RAPID.
A tutorial on how to display a map and a hydrograph of RAPID flow rate computations in ArcGIS.

Animations
In the following animations of stream flow, the thickness of river reaches varies with the magnitude of the flow rate going through them. One can see the flow waves propagating downstream. All these animations were prepared using 3-hourly outputs from RAPID. They can be played directly from this webpage (full-screen mode available) or downloaded in .avi, .flv and .mp4 formats. The latter can be uploaded to and played on iPhones.

This first animation is of the San Antonio and Guadalupe Basins in Texas, USA, over four months (between 2007-06-01 and 2007-09-30). 3-hourly surface and subsurface runoff was produced by the Noah-MP land surface model using a combination of NARR and NEXRAD for atmospheric forcing. RAPID was run at a 15-minute time step. Download .avi, .flv or .mp4. Or, play directly from iPhone.

This second animation is of all the rivers in SIM-France, over four months (between 1995-12-01 and 1996-03-31). The computational domain of SIM-France covers all of Metropolitan France, including Corsica. Parts of Spain, Switzerland, Germany and Belgium are also included where their drainage area flows through France. 3-hourly surface runoff was produced by the ISBA land surface model using SAFRAN for atmospheric forcing. Daily exchanges between aquifers and rivers were computed by MODCOU. RAPID was run at a 30-minute time step. Download .avi, .flv or .mp4. Or, play directly from iPhone.

This third animation is of the Texas Gulf Coast Hydrologic Region, USA, over four months (between 2004-03-01 and 2004-06-30). 3-hourly surface and subsurface runoff was produced by the Noah-MP land surface model using NLDAS2 atmospheric forcing, and RAPID was run at a 15-minute time step. Download .avi, .flv or .mp4. Or, play directly from iPhone.

This fourth animation is of the Mississippi River Basin, USA, over four months (between 2008-03-01 and 2008-05-31). Hourly surface and subsurface runoff by the Mosaic land surface model and available from NLDAS2 were accumulated every 3 hours. Atmospheric forcing was from NLDAS2 as well. RAPID was run at a 15-minute time step. This RAPID simulation was produced by Ahmad A. Tavakoly. Download .avi, .flv or .mp4. Or, play directly from iPhone.