Biophysical Methods and Data Analysis for Simulating Overland Flow in
the Everglades
- Judson Harvey,
- Jay Choi
Abstract
The Everglades in south Florida supply fresh drinking water for more
than 7 million people, host a National Park, and are classified as a
Ramsar wetland of international distinction. Predicting trajectories of
water flow and water storage changes in the future is important to
managing the Congressionally authorized restoration of the Everglades.
Here we describe the needed data sources and analysis approaches to
build the inputs for biophysically based modeling that can protect water
and ecological resources in the face of changing water management and
climate conditions. A biophysical approach to modeling overland flow in
the Everglades can help predict future outcomes for ecological habitat,
water storage during droughts, and water conveyance during floods. The
needed data include measurements of vegetation stem architecture,
microtopography, and landscape pattern metrics. Stem architecture
measurements present the opportunity to estimate flow roughness of
distinct vegetation communities based on hydraulic principles. At a
larger scale, the microtopography and the connectivity of the sloughs
between ridges offer a way to quantify the effects of flow blockage and
tortuous flow paths on overland flow. Combined with theory these data
provide the capacity to simulate overland flow in both the historical,
pre-drainage Everglades as well as in the present-day managed
Everglades. Also provided are the hydrologic data, e.g., water slopes,
water depths and overland flow velocities, that can be used to verify a
biophysical model. Ultimately, the purpose is to anticipate how changing
flow and water depth will interact with evolving vegetation and
landscape conditions to influence future water availability for society
and for the ecosystem, both in the Everglades and in other low-gradient
floodplains.