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Chapter 1 INTRODUCTION & ACCESS

Understanding groundwater systems has traditionally been hampered by a lack of data - both for the analysis
or characterization of the system and for conceptualizing, building, calibrating and validating numerical
models. In recent times, though, the geospatial and digital revolutions have led to the availability of massive
datasets such as high-resolution Digital Elevation Models (DEMs) or detailed climate information
(precipitation, temperature). In spite of the availability of this “big data”, its size renders it immovable and
hard to maneuver. As a result, the tools and techniques required to efficiently utilize this data have not kept
pace with the rate of data “creation.” Moreover, the time required for processing the data makes it highly
impractical to accomplish, especially considering that the same process must be repeated for every project.
Obviously, this is an impractical way of efficiently using this data and needs improvement.

1.1 Overview of MAGNET

MAGNET is a data-enabled modeling system built on pre-processed, fully-assembled framework data, i.e.,
data needed to conceptualize and characterize the system (e.g., DEM, recharge estimates, etc.) in a ready-
to-use form at the “global scale”. Even though the data provided by the system may not completely satisfy
the requirements of a particular study, it provides the vast majority of data needed to build a preliminary
model. Thus, the modeler can use the “data-ready” system to refine or modify the preliminary model as
desired by adding site-specific details, and also guide further data collection efforts.

The system allows users not only to access and utilize pre-processed big datasets, but also to do so in real-
time and interactively. Within the GIS-enabled modeling environment, users can zoom in anywhere to
create a data-enabled model groundwater flow and contaminant transport, and immediately evaluate model
performance using physical groundwater data available within the study area. All model inputs and
representations (e.g. conceptual/structural, sources and sinks, number of layers, grid resolution, and display
parameters) can be interactively modified and further customized based on study objectives and other
available (local) data, as well as user experience and expertise. The users can: 1) change assumptions,
conceptual framework, resolution, or representation, and immediately see the integrated effects, the
ultimate implications, and the complex interrelationships presented intelligently in a meaningful context;
2) initiate or pause contaminant particle tracking or reactive plume modeling; and 3) perform well (head
and concentration) monitoring and perform mass balance analyses.

The MAGNET modeling environment is designed in such a way that modeler feels as though they are using
a single model that provides multiple options. The process starts with a global Google Map that allows
users to select an area of interest, after which a geo-referencing model is determined based on the area
selected. A GIS-based interface is provided for the user to fine-tune the computational domain and to add
additional data such as i) polyline or polygon data used to represent a stream/lake in the model, or ii) geo-
referenced images used as a base-map for digitizing a geological formation. For example, a polyline layer
could be either treated as a stream with attributes of stage, leakance and bed elevation or as an injection
trench with a prescribed flux; and a polygon layer could be defined as a lake with attributes of lake level
and leakance, or as a contaminant source.

The remaining chapters of this User Manual explain the different functionalities of the MAGNET modeling
platform. Chapter 2 overviews the MAGNET Modeling Environment and the assortment of modeling,
visualization and analytical tools that are available. Chapters 3 through 6 guide users through the different

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