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Water bodies, watersheds and storm water

Upper St. Johns River Restoration Initiative

Meet the Technical Team

Name:Dianne L. Hall, Ph.D.

Title:Environmental Scientist V — Ecologist


  • Doctorate, Biology, Texas Tech University
    • Minors — Environmental Science, Biostatistics
  • Master of Science, Biology, Texas Tech University
  • Bachelor of Science, Biology, University of Central Florida


Dr. Hall has been with the district since December 2002, specializing in wetland restoration and adaptive management of wetland systems.

Primary Initiative Responsibility:

Dr. Hall’s work on the initiative team includes managing and collaborating with the University of Central Florida on the ongoing research project concerning the impact of willows on the hydrology of floodplain marshes, completing all biological monitoring required by the U.S. Fish and Wildlife Service and the U.S. Army Corp of Engineers associated with the construction permits for the Fellsmere Water Management Area; assisting in the development of hydrologic and environmental restoration plans for St. Johns Marsh Conservation Area, and managing and coordinating with the Natural Resource Conservation Service on the cooperative wetland restoration project at Turkey Creek (Seminole County).

Name:Tom Jobes

Title:Senior Engineer Scientist


  • Bachelor of Arts, Applied Mathematics-Environmental Science, Harvard College


Jobes has been with the district since November 2006, specializing in watershed hydrology, hydraulic and water quality modeling. He has 23 years of experience with HSPF (Hydrologic Simulation Program — FORTRAN, a standard watershed modeling software package), including software devel­opment and watershed hydrologic and water quality modeling.

Primary Initiative Responsibility:

Jobes is tasked with most of the watershed modeling performed for analysis of the Upper St. Johns River Basin Restoration Initiative, including Fellsmere Water Management Area, as well as some hydraulic modeling, GIS analysis and inter-bureau coordination.

Name:Lawrence Keenan, Ph.D.

Title:Environmental Scientist V


  • Doctorate, Zoology (Ecology), Clemson University
  • Bachelor of Science, Biology, Valdosta State University


Dr. Keenan has been with the district since September 1990, specializing in ecohydrology and water quality.

Primary Initiative Responsibility:

Dr. Keenan oversees the total maximum daily load development and compliance for water quality in the Upper St. Johns River Basin and studies on evapotranspiration under varying vegetation and water level conditions. He also works on environmental hydrologic criteria development and application, which will optimize the timing, depth and return interval of the water in different communities.

Name:Steven J. Miller

Title:Supervising Environmental Scientist


  • Master of Science, Environmental Biology (Aquatic Ecology), Eastern Illinois University
  • Bachelor of Science, Environmental Biology, Eastern Illinois University


Miller has been with the district since June 1991, specializing in wetlands restoration and manage­ment, hydroecology and fisheries.

Primary Initiative Responsibility:

Miller guides water management activities in the Upper St. Johns River Basin Project to maximize environmental benefits of the project and works on fisheries related issues throughout the district.

Name:Doug Voltolina

Title:Land Manager


  • Bachelor of Science, Forest Resources and Conservation, University of Florida


Voltolina has been with the district since November 1996, specializing in management of public lands.

Primary Initiative Responsibility:

Voltolina oversees the land management program in the Upper St. Johns River Basin. His duties include all aspects of public use and recreation on district property in the upper basin, such as boating, fishing, hiking, biking and hunting. He also is the region’s “burn boss,” conducting prescribed burns on district property. Voltolina is primarily responsible for the development of the Upper Basin Recreation Access Plan.


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St. Johns River Water Management District
4049 Reid Street, Palatka, FL 32177
(800) 725-5922