The Southwest Florida Water Management
District (SWFWMD) is one of five Districts in the State legislatively charged
with regulation of the withdrawal and use of ground and surface waters by public
and private users. Regulation is accomplished through the issuance of a Water
Use Permits (WUP) for agricultural, industrial, potable public supply, recreational
and mining uses that exceed certain minimum thresholds. Applications for groundwater
withdrawals within SWFWMD that require a permit must undergo an impact evaluation
to demonstrate that the proposed withdrawals will not cause unacceptable adverse
impacts to environmental systems or existing legal users on an individual and
cumulative basis. SWFWMD hydrologists evaluate the permit applications using
groundwater models to assess these impacts. In the past, the assessments have
been conducted using simplified models. Recently, SWFWMD has developed a tool
to take existing large-scale regional models and make local predictions at the
scale of a well or well field. This new tool, called Focus Telescopic Mesh Refinement
(Focus TMR),
automatically creates a new refined model from the regional model. Aquifer properties
are derived from the regional model and can be adjusted by the user. Boundary
conditions at the edge of the new model are also derived from the regional model,
as in existing telescopic mesh refinement techniques. Where the new Focus TMR
differs from existing techniques is that wells are reimported from a database
and surface hydrologic boundary conditions (e.g. wetlands, lakes, streams, and
rivers) are recreated from a Geographic Information System (GIS). In addition,
the grid is automatically refined around the well(s). Standardized reports are
also created to assist the District hydrologists in assessing impacts.