Open-source software packages for wave propagation and surface flows.


Clawpack is an open-source project and collection of software packages for hyperbolic conservation laws and related sytems of PDEs. These systems commonly govern problems exhibiting wave-propagation which arise across the scientific disciplines.


Clawpack was established in 1994 by Randall LeVeque (Univ. of Wash.) to implement a finite volume framework utilizing wave-propagation algorithms applicable to general nonlinear hyperbolic systems. These numerical methods belong to the class of high-resolution Godunov schemes with limiters which provide stability and convergence to physically admissable discontinuous weak solutions, such as shock-capturing for conservation laws. Clawpack also provides patch-based adaptive mesh refinement (AMR) originally developed by Marsha Berger (NYU) and later formulated in the numerical wave-propagation framework. For more information and links to relevant publications and research, see the official Clawpack site:

source code and repositories

Clawpack source code and repositories are hosted on github:

Links to documentation and instructions for developers can also be found at


GeoClaw is an open-source package within the Clawpack project for simulating shallow earth-surface flows involving water-wave propagation and inundation (e.g., tsunamis, storm surges and general overland flooding problems).


GeoClaw evolved from a collection of algorithms developed for modeling tsunamis in the Clawpack adaptive numerical framework (George, 2006; George, 2008; LeVeque, George, et al., 2011). These algorithms provide robust inundation capturing and well-balanced resolution in the presence of dominant steady states (e.g., ocean at rest). Additionally, AMR schemes that preserve well-balancing and inundation capturing in conjunction with mass, momentum and energy conservation enable global-scale tsunami propagation and local-scale inundation in reasonably efficient single simulations. These methods are more generally applicable to shallow free-surface flows over topography, which motivated the extension of GeoClaw to overland flooding problems in irregular terrain (e.g, George, 2010; Berger, George, et al., 2011). Later extensions of these algorithms were developed for storm-surge applications (e.g., Mandli, 2014). GeoClaw is now used for a variety of applications involving shallow water flows over topography. Features and enhancements continue to be developed within the Clawpack project (e.g., Mandli, Ahmadia, et al., 2016). See Projects for some examples and galleries and for links to related research.

source code and repositories

GeoClaw is a subpackage available with the latest versions (v5) of Clawpack, hosted on github:

Information related to GeoClaw development is available at the official Clawpack site ( and


D-Claw is an open-source package for modeling shallow two-phase flows, such as dense granular-fluid mixtures like landslides and debris flows. It can also be used for modeling hybrid problems involving the interaction of variably concentrated granular mixtures and water (eg., landslide-generated tsunamis, dam breach floods, fluid or solid entrainment by inundating or overlying flows).


D-Claw was developed in collaboration with Richard Iverson at the USGS. It embodies a synthesis of the independent lines of research behind Clawpack and GeoClaw with granular dynamics and landslide physics research by Iverson (e.g., Iverson, 1997). A detailed description of the model underlying the D-Claw software is provided by Iverson & George (2014) and George & Iverson (2014). For further background information and some application examples, see projects

source code and repositories

The documentation for the latest version of Clawpack and GeoClaw (v5), available at, provides a general overview of the methodologies underlying the D-Claw software. However, D-Claw is built on legacy versions of Clawpack and GeoClaw (v4). The Clawpack v4 source code is available at An additional legacy version of GeoClaw (v4) is available at D-Claw documentation is still in progress, but basic usage instructions are available in source-code and application repositories below. D-Claw inherits the Clawpack licenses and user agreeements.

The source code and latest git repository for D-Claw are available on github:

A repository for applications is also available:

The application repository is in progress, as is documentation for D-Claw. If you would like to make contributions to either of these repositories, please follow the development workflow used for Clawpack, described at Briefly, please fork the repositories to your own github account, develop on a new or feature branch, and issue pull requests from that branch to github/geoflows.


  • Local adaptive mesh refinement for shock hydrodynamics. M.J. Berger and P. Colella, 1989. J. Comput. Phys., 82: 64-84.
  • The GeoClaw software for depth-averaged flows with adaptive refinement. M. J. Berger, D. L. George, R. J. LeVeque and K. T. Mandli, 2011. Advances in Water Resources, 34: 1195–1206. doi: 10.1016/j.advwatres.2011.02.016. pdf
  • Finite volume methods and adaptive refinement for tsunami propagation and inundation, D.L. George, 2006. Ph.D. thesis, University of Washington, Seattle. pdf
  • Augmented Riemann solvers for the shallow water equations over variable topography with steady states and inundation. D. L. George, 2008. J. Comput. Phys., 227(6): 3089–3113. pdf
  • A depth-averaged debris-flow model that includes the effects of evolving dilatancy: 2. Numerical predictions and experimental tests. D. L. George and R. M. Iverson, 2014. Proc. R. Soc. A, 470 (2170). pdf
  • A depth-averaged debris-flow model that includes the effects of evolving dilatancy: 1. Physical basis. R. M. Iverson and D. L. George, 2014. Proc. R. Soc. A, 470 (2170). pdf
  • Finite volume methods for hyperbolic problems. R.J. LeVeque, 2002. Texts in Applied Mathematics, Cambridge University Press.
  • Tsunami modeling with adaptively refined finite volume methods. R.J. LeVeque, D.L. George and M.J. Berger, 2011. Acta Numerica 20, pp. 211–289. Arieh Iserles, ed. pdf
  • Adaptive mesh refinement for storm surge. K.T. Mandli and C.N. Dawson, 2014. Ocean Modeling, V. 75, 36-50.
  • Clawpack: building an open source ecosystem for solving hyperbolic PDEs. K.T. Mandli, A.J. Ahmadia, M.J. Berger, D. Calhoun, D.L. George, Y. Hadjimichael, D.I. Ketcheson, G.I. Lemoine and R.J. LeVeque, 2016. Peer J Computer Science, 2, e68. pdf