Copyright (c) 2017 Battelle Memorial Institute Licensed under modified BSD License. A copy of this license can be found in the LICENSE file in the top level directory of this distribution.

Home Page: http://mass1.pnnl.gov Github repository: https://github.com/pnnl/mass1

MASS1 is a one-dimensional unsteady hydrodynamic and water quality model capable of simulating open channel flows, water surface elevations, dissolved gas, and water temperature. The model is applicable to any branched channel system. Because MASS1 uses cross-section averaging, only single values of water surface elevation, velocity, discharge, and temperature are produced at each cross-section location along the river course. Lateral (i.e., across the river channel) and vertical variations of these quantities are not simulated.

MASS1 was developed by Pacific Northwest National Laboratory (PNNL). It is a research code, written for applications and computer platforms specific to the developers. Others may, or may not, find it useful.

The MASS1 source code is currently hosted on PNNL's internal Git repository. MASS1 shares some code with other applications, which is included in MASS1 as a Git sub-module. Do the following to check out the code:

git clone https://stash.pnnl.gov/scm/~d3g096/mass1.git
cd mass1
git submodule update --init

MASS1 has been used primarily on UNIX, Linux, and Mac OS X systems. The following describes how to build MASS1 on those platforms. It has been built and used on Windows systems, but rarely. The following should work on Windows if Cygwin or MinGW is utilized. A native Windows build may be available in the future.

MASS1 is a relatively portable, vanilla Fortran 90/95 code. It has been built and used on UNIX, Linux, Mac OS X, and Windows. A Fortran 90/95 compiler is required. MASS1 is currently developed and tested on Mac OS X and Linux using the following compilers:

• GNU Fortran, Version 4.1 or higher

• Intel Fortran, Version 10 or higher

In general, the Intel compiler produces a faster executable, but for most applications, this is not noticable. In the past, Fortran compilers from NAG, Absoft, IBM, and others have worked.

Several optional Perl pre/post-processing scripts are provided. These use the following Perl modules:

• Date::Manip

• PDL

• PDL::Graphics::PGPLOT::Window

When MASS1 code is configured, the system's Perl installation is queried to see if the scripts can be used. If not, the scripts are not configured or installed.

In addition to the Perl scripts, some optional Python pre/post-processing scripts are also provided.

There is an optional R script for reading MASS1 time series output and boundary condition files.

MASS1 uses the GNU Build System to build MASS1. The configure script is used to query the system and determine if the compiler has sufficient capability to compile MASS1. On most systems, simply executing the configure script is sufficient, but sometimes options are required. To get a list of options,

./configure --help

A typical way to require the GNU Fortran compiler and trapping of floating point errors:

./configure FC=gfortran FCFLAGS="-O2 -ffpe-trap=invalid,zero,overflow"

Similarly, for the Intel Fortran compiler:

./configure FC=ifort FCFLAGS="-O3 -fpe0"

MASS1 is a command line application. There is no graphical user interface. All input and output are plain text files. There is very little documentation, other than the code itself.

The first step in a MASS1 application is to define the topology of the river system to be simulated. The topological definition defines how the channel system is connected as well as the location and type of hydraulic control structures. The domain into a set of links, each representing a single river reach. The ends of each link either represent a boundary, at which river conditions are specified, or connect to one or more other links. Each link is further divided into series of computational points, where the hydrodynamic and transport equations are discretized.

When run, MASS1 expects to find a configuration file named mass1.cfg.

If you use MASS1, please cite

Richmond, M.C., Perkins, W.A., 2009. Efficient calculation of dewatered and entrapped areas using hydrodynamic modeling and GIS. Environmental Modelling & Software 24, 1447–1456. doi:10.1016/j.envsoft.2009.06.001

For examples of MASS1 use, see the bibliography.