Prof. Craig's interests include the development and application of new modelling approaches for
addressing difficult environmental/water resources problems in both groundwater and surface water
systems. He is invested in making these tools and techniques accessible and useful to consultants,
educators, and regulators.
When used correctly, environmental models can inform policy makers, increase our understanding of
complex systems, and help predict the effects of man's efforts to clean up pollution, use our
available water resources, and control climate change. Prof. Craig and his research group work both
to improve the science of environmental modelling and, as a nod to basic curiosity-driven research,
ambitiously push the boundaries of what is possible using analytical and semi-analytical methods.
Mixed Regional and Local Groundwater Flow Modelling
Groundwater flow models are used to improve our understanding of complex aquifer
systems to better inform water supply and water quality policy. While existing numerical
methods are suitable for simulating large scale systems or local systems, better approaches
are needed to integrate the two scales. Prof. Craig is currently addressing this issue via
integrating the analytic element method (AEM) which is advantageous at large scales, and the
finite element method (FEM), more appropriate for complex local-scale phenomena. He is also
working with Dr. Robert Gracie on
extension of the extended finite element method (XFEM) to mixed-scale problems of carbon
sequestration and reservoir leakage in multilayer aquifer systems.
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Analytical Solutions for Flow in Heterogeneous Aquifers
There are very few analytical solution approaches for simulating flow through porous
media with heterogeneous properties. Prof. Craig is currently looking into some novel methods
based upon Bers-Vekua theory of pseudoanalytic functions to obtain exact solutions to
heterogeneous porous media flow problems. These methods may eventually be used to benchmark
numerical simulation methods and better understand the impact of heterogenity on pollutant
transport.
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Upscaling and Robust Modelling of Hydrologic Phenomena
Surface water models are burdened with a
difficult task: they are expected to successfully simulate the
interaction of a variety of complicated processes (infiltration,
evapotranspiration, heat transfer, etc.) at large scales in a
computationally efficient manner. To complicate issues, these processes
are extremely variable (both in time and space). Prof. Craig and his
students are investigating how to use distribution-based approaches to
successfully model a variety of phenomenon at mixed spatial and
temporal scales. His research group is also working on the development
of a robust computational framework, Raven, for assessing the impacts of modelling decisions on model output.
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Improved Design of Horizontal Geothermal Heat Loops
Geothermal is one of the few sustainable energy options that can survive today without government
subsidy. However, there is still room for improvement in how we design and install backyard geothermal
systems. Many existing systems are overdesigned because we just don’t have a full understanding of
heat transport in the subsurface adjacent to the ground loops. The impact of soil variability and
ground loop configuration remain elusive, despite the potential impact both can have on long-term performance.
With a combination of field and computational research, students Simon Haslam and Richard
Simms are working
with partner NextEnergy, Inc., attempting
to develop a better understanding of the processes which control outdoor loop effectiveness, and determine
how we can design more effective systems on smaller
land footprints.
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Analytical (Series) Solutions for Regional Groundwater Flow
Semi-analytical series solution approaches are an underappreciated and underinvestigated
method for simulating a wide range of phenomena in fluid flow, soil,
and solid mechanics. The methods can handle complex system geometry
without internal discretization, improve with decreasing aspect ratio
of the model domain, and provide solutions with near-spectral accuracy.
Prof. Craig and his PhD student Sanders Wong are currently looking into the
development of series solution approaches for multilayer aquifers in
multiple dimensions.
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Novel Analytical Contaminant Transport Solutions
Analytical solutions for
pollutant transport simulation are widely used for preliminary
remediation design and analysis, groundwater and atmospheric risk
assessment, and regulatory applications. While often useful, critical
approximations and assumptions limit their applicability for many
investigations and users are forced to rely on more complicated
numerical models, which can be cumbersome or inefficient for hypothesis
testing. Prof. Craig and his research group work towards extending
analytical transport models to
be useful in more complex situations with non-uniform flow, complex
chemical reactions, and site-specific conditions.
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Prospective Research Projects for Graduate, Co-op, and URA Students
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There are many project ideas to work on and so little time...
Developing robust numerical and semi-analytical solution methods for simulating:
- Groundwater-surface water interaction
- Groundwater flow in smoothly heterogeneous media
- Complex semi-distributed surface water modelling
- Saturated/unsaturated flow systems
- Propagation of uncertainty in flow and contaminant transport models
Development of coupled analytical / numerical solution methods:
- Series solution approaches for regional scale groundwater modelling
- Mixed analytic element-finite element models for groundwater flow simulation
- Numerical mapping of analytical contaminant transport solutions to non-uniform flow fields
- Improved screening models and evaluation methods for capture-zone delineation
Application of numerical models to difficult problems:
- Sustainability and protection of groundwater-surface water resources
- Understanding and quantifying regional water balances
- Complex reactive contaminant transport problems
- Understanding the effects of environmental system heterogeneity
...I try to do these all at once. It hasn't worked yet.
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Current Graduate Students
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Tussanee Nettasana, Ph.D. Candidate
(Co-supervised with Prof. Bryan Tolson)
- B.Sc. Geology, Chiang Mai University, M.Sc. Hydrogeology, Khon Kaen University
- Thesis Title: "Conceptual model uncertainty in the management of the Chi River Basin, Thailand"
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Andy Snowdon, Ph.D. Candidate
- B.Sc. Geology, University of Guelph, M.A.Sc. Civil & Environmental Engineering, University of Waterloo
- Thesis Topic: Upscaling groundwater-surface water interactions in regional water balance models
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Sanders Wong, Ph.D. Candidate
- B.Sc. Civil Engineering, M.A.Sc. Mathematics, University of Guelph
- Thesis Title : "Series solution methods for regional groundwater systems with natural stratigraphy"
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Simon Haslam,M.A.Sc.Student
- B.Sc. Geological Engineering, University of Waterloo
- Thesis Topic: Improved design tools and loop configurations for geothermal heat loops
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Richard Simms,M.A.Sc.Student
- B.Sc. Computational Science (Earth Science Specialization), University of Waterloo
- Thesis Topic: Modelling horizontal geothermal heat loop systems using XFEM
At our geoexchange monitoring site during system installation. Guelph, Nov 2010.
Left to Right: Richard Simms, James Craig, Dave Broderecht (from
NextEnergy), Simon Haslam
Computational hydrology researchers pretending to be field savvy. Yukon, Nov 2008.
Left to Right: Lucy Liu, Angela MacLean, Andy Snowdon, Frank Seglenieks, James Craig;
Bottom: Carol Soulis, Kaitlyn McIntyre, Bryan Tolson
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Lucy (Guoxiang) Liu, Ph.D.
(Co-supervised with Prof. Ric Soulis)
- Thesis Title: "Improved interflow and infiltration algorithms for distributed hydrological models"
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Cameron Dunning, M.A.Sc.
(Co-supervised with Prof. Ric Soulis)
- Thesis Title : "Hydrological modeling of the Upper South Saskatchewan River basin: Multi-basin calibration and gauge de-clustering analysis"
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Chao Huo, M.A.Sc.
(Co-supervised with Prof. Neil Thomson)
- Thesis Title : "Mathematical simulation of a dipole delivery system for in situ remediation"
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Erin L. Jones,M.A.Sc. [Joint with Biology]
(Co-supervised with Prof. Ralph Smith)
- B.Sc. Environmental Engineering, University of Waterloo
- Thesis Title: "Ecological modelling of Lake Erie : Sensitivity analysis and simulation of nutrient, phytoplankton, and zooplankton dynamics"
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Andy Snowdon, M.A.Sc.
- Thesis Title: "Improved numerical methods for distributed hydrological models"
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