1	Hydrogeology of Lake Jackson Thomas Kwader, PhD, PG Alan Niedoroda, PhD, PG
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6	Lake Jackson & Watershed Basin: 43 Sq Mi Lake Area: 6.5 Sq Mi Closed Basin: Water level controlled by: Direct rainfall Surface run-off Shallow aquifers seepage Evaporation Loss to deeper aquifer
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8	Sink Hole History – 1950s 1957: Lime sink opened September 1982: Porter Hole #1 opened, plugged itself September 1999: Porter Hole #2 opened and stayed opened until 2005 Summer 2007: Porter Hole #1 reopened
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12	Perched Lake Lake Jackson – Without Sink Hole
13	Perched Lake Lake Jackson – With Sink Hole
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17	Direct Funding Direct funding for the restoration: Leon County: $4,460,250 Florida Legislature: $2,650,000 Northwest Florida WMD - $500,000 Florida FWCC- $396,633 Florida DEP - $250,000 In addition to the direct funding, the project partners provided substantial staffing and services
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23	To Plug or Not To Plug - Pros Safety Hazard: Deep open hole 30 – 40 feet deep
24	To Plug or Not To Plug - Pros Recreational Value: Most valuable natural resources of Leon County and by far the largest and best for: Outstanding Florida Water and designated aquatic preserve Fishing - famous bass fishing lake - $10M in revenue 1980 Boating Water sports Recreation – swimming/canoeing
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27	To Plug or Not To Plug - Pros Water Quality Concern: Direct conduit for possible contamination of Floridan Aquifer from stormwater runoff containing petroleum products nutrients from fertilizers (nitrates) herbicides pesticides bacteria viruses toxic algae (microcystis) animal waste
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32	To Plug or Not To Plug - Cons Flooding: Helps control flooding by draining water Draining: Period draining of lake is good to reduce vegetation
33	To Plug or Not To Plug - Compromise Build a levee or berm around sinkhole with: Overflow capabilities – to drain during flood events Gates - to drain lake dry if so desired
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