Meet our leaders

Michael A. Register

Michael A. Register, P.E.

Executive Director

Michael A. Register was appointed Executive Director by the District’s Governing Board on Sept. 14, 2021. He has been with the St. Johns River Water Management District since 1990.

During his tenure with the district, he has worked in a variety of areas, including environmental resource permitting, consumptive use permitting, water supply planning, engineering and environmental sciences.

As director of the Division of Water Supply Planning and Assessment, he was responsible for overseeing the Bureau of Watershed Management and Modeling and the Bureau of Water Supply Planning. These work groups are responsible for performing surface water and groundwater modeling, developing minimum flow and levels (MFLs) and prevention/recovery strategies, and conducting the district’s water supply planning efforts.

Register holds Bachelor of Science and Master of Engineering degrees in agricultural engineering from the University of Florida. While at the University of Florida, he conducted research on using reduced irrigation rates to freeze protect commercial foliage crops. He is a registered professional engineer in Florida.

Mary Ellen Winkler headshot

Mary Ellen Winkler

Assistant Executive Director

Mary Ellen Winkler is the Assistant Executive Director with the St. Johns River Water Management District. In this role, she oversees the work of the District’s Divisions of Water Resources, Water Supply Planning and Assessment, Infrastructure and Land Resources, and Basin Management and Modeling. She also provides oversight for the District’s Real Estate Services office and Chief Resilience Officer.

Ms. Winkler has been with the District since 1999 and most recently served as General Counsel. Prior to that, she served as an Assistant, Senior Assistant and Deputy General Counsel. During her time with the District, she has received several awards for her service to the agency. While with the Office of General Counsel, her primary areas of practice have included consumptive use and environmental resource permitting, minimum flows and levels and water supply planning. Ms. Winkler has also represented the District in numerous cases before the State of Florida Division of Administrative Hearings.

A native of Brevard County in Florida’s Space Coast, Ms. Winkler graduated with high honors from the University of Florida College of Law where she was awarded the Order of the Coif and Order of the Barrister. She previously graduated summa cum laude with a Bachelor of Science in Engineering from the University of Central Florida and also earned a Master of Engineering in Environmental Engineering from the University of Florida where she was a U.S. Department of Energy Applied Health Physics Fellow.

Headshot of Brad Purcell

Brad Purcell

Chief of Staff

Brad Purcell is Chief of Staff at the St. Johns River Water Management District, bringing with him more than 30 years of experience in environmental work in the public and private sectors.

As Chief of Staff, Purcell provides leadership to the Regulatory Services, Governmental Affairs Program, Strategic Communications and Engagement, Finance, Information Technology, Safety and Risk, and Business and Administration Service functions.

Purcell began his career working for the District from 1985 to 2000 and returned to the agency in December 2012. Prior to being named Chief of Staff in October 2021, Purcell worked in a variety of capacities for the agency, including the Director of Process Excellence and Special Projects and Service Center Director for the Palatka headquarters, and served as Ombudsman.

In addition to three terms of elected office as a county commissioner in Putnam County, he was president of a multidisciplinary planning, engineering and environmental science consulting firm and worked for Georgia Pacific as an Engineer focused on environmental compliance.

Purcell earned a Bachelor of Science degree in Business Administration from Jacksonville University and a black belt from the Lean Six Sigma program at Flagler College. He has received honors such as Legislator of the Year from the Northeast Florida Association of Realtors, Presidential Advocacy Award from the Florida Association of Counties and the Division of Emergency Management’s Florida Outstanding Service Award.

Outside the office, he has served as Chairman of the Board of Directors for the Putnam County YMCA, Board of Directors for the First Coast Community Credit Union, Board member for the United Way of Putnam/St. Johns County, and Board of Trustees for Putnam Memorial Hospital.

Headshot of Jeff Prather

Jeff Prather

Director
Division of Regulatory Services

Jeff Prather joined the St. Johns River Water Management District in July 2018, bringing more than 20 years’ experience in environmental protection to his role as director of the district’s Division of Regulatory Services.

Under his leadership, the division is responsible for implementing the district’s Consumptive Use and Environmental Resource Permitting programs. This division encompasses the Bureau of Water Use Regulation, which is responsible for water use permitting, water well construction permitting, water well contractor licensing, compliance and enforcement, and the Bureau of Environmental Resource Regulation, which is responsible for environmental resource permitting, administration compliance and enforcement.

Prior to coming to the district, Prather worked for more than 18 years in the Florida Department of Environmental Protection, including as Director of the Central District Office; and Deputy Director and Communications Director/Ombudsman, also in the Central District Office. He also worked in the private sector with Siemens Information and Communications Systems, where he was the Environmental, Safety and Health Manager. In the public and private sectors, he has worked with diverse groups of stakeholders in all areas of environmental protection. Prather has served in the community as a governor’s appointee to the Wekiva River Basin Commission.

A graduate of Ferris State University (Michigan), he holds Bachelor’s Degrees in biology and industrial and environmental health management. Outside of work, he enjoys camping in Florida State Parks and is an avid bass fisherman.

Headshot of Erich Marzolf

Erich R. Marzolf, Ph.D.

Director
Division of Water Resources

Dr. Erich Marzolf worked for the St. Johns River Water Management District from 1994 to 2012 and returned to the agency in October 2015 after three years as the Suwannee River Water Management District’s Water Resources division director.

In his current role, Marzolf is responsible for directing the St. Johns District’s aquatic sciences, water resource management activities, and hydrologic and water quality data collection efforts.

During his tenure with the district, he has worked as a limnologist, working on the Upper and Middle St. Johns River basins’ restoration programs as a supervising scientist with the Lake Apopka restoration program. He has also worked as a technical program manager for the Middle St. Johns River and Orange Creek basins, overseeing all aspects of the district’s scientific work in the basins.

Marzolf holds a Bachelor of Arts degree in biology from Colorado College and master’s and doctorate degrees in ecology from the University of California Davis, where he focused on subalpine lake ecology. Marzolf moved to Knoxville, TN, to work as a post-doctoral scientist at the Oak Ridge National Laboratory where he worked on nutrient cycling in stream ecosystems.

Head shot of Dale Jenkins

Dale Jenkins, P.G.

Director
Division of Infrastructure and Land Resources

Dale Jenkins is division director for the St. Johns River Water Management District’s Division of Infrastructure and Land Resources, where he began work in summer 2015.

He directs the division’s work for the bureaus of Operations and Maintenance, District Projects and Construction, Transportation and Facilities, and Land Resources leading in the bureaus’ strategic planning activities, budgeting, identification of key projects and priorities, and providing proactive insight into possible challenges and solutions. This division is responsible for district-led project feasibility and pilot projects, engineering and construction of district water resource restoration projects, flood control structure operation and maintenance, transportation and facilities maintenance, as well as managing the public conservation areas owned and managed by the district.

Mr. Jenkins previously served for five years as the district’s Chief of the Bureau of Project Management. In that role, his responsibilities included leading a team of project managers and professionals that implement the district’s annual Districtwide and REDI community / innovative projects cost-share funding programs.

Prior to joining the St. Johns District, Mr. Jenkins served as a Senior Hydrogeologist at the Suwannee River Water Management District for six years, where his responsibilities included the implementation of district-led water resources projects and water supply assessment and planning efforts.

Mr. Jenkins is a water resources professional with more than 36 years of planning, assessment and management experience encompassing water resources and related projects. Before joining the water managements districts, his experience ranged from managing water resource assessments to providing technical support for the acquisition of various permits. Project work included water supply planning, watershed studies, groundwater and surface water resource assessments, wellfield studies, and alternative water supply assessments.

He holds Bachelor of Science and Master of Science degrees in Geology from the University of Florida.

Headshot of Clay Coarsey

Clay Coarsey, P.E.

Director
Division of Water Supply Planning and Assessment

Clay Coarsey has been with the St. Johns River Water Management District since 2016. Prior to becoming division director, he served as bureau chief for the Bureau of Water Supply Planning, a bureau responsible for identifying future water supply needs for a 20-year planning horizon, and programs and projects needed to ensure sustainable supplies. Bureau staff’s work includes developing the water supply plans in the District’s three planning regions.

He began his career at the District as the lead hydrologist in the District’s Consumptive Use Permitting Program at Palatka Headquarters. He later served as a technical program manager over the District’s Groundwater Modeling Section. Prior to coming to the St. Johns District, he worked for 12 years at the Suwannee River Water Management District as a professional engineer. His other professional experience includes adjunct instructor of mathematics at Lake City Community College and as an undergraduate research assistant at the University of Florida.

Coarsey is a licensed professional engineer in the State of Florida. He holds a Bachelor’s degree in agricultural and biological engineering from the University of Florida. He is also an active volunteer in his community.

Michelle Brown headshot

Michelle Brown, P.E.

Director
Division of Basin Management and Modeling

Michelle Brown has been with the St. Johns River Water Management District since 2016. Prior to becoming division director, she served as the bureau chief for the Bureau of Watershed Management and Modeling.

In her role as division director, Brown coordinates the work that encompasses two bureaus: the Bureau of Watershed Management and Modeling and the Bureau of Basin Management and Project Development. Together, the division is responsible for developing and implementing detailed work plans to address the science, data and projects needed to address water resource challenges in the drainage basins within the District, as well as for performing surface water and hydrodynamic modeling to support District efforts such as minimum flows and levels and water supply planning. The Districtwide and Rural Economic Development Initiative (REDI) and Innovative Projects Cost-Share programs are also administered through the division.

Brown has more than 15 years of engineering experience, having previously served as an engineer, senior project manager and environmental resource program coordinator at the District. Prior to joining the District, she worked as an engineer in the private sector for 10 years.

A graduate of the University of Florida, she holds a Bachelor of Science degree in Civil Engineering and is a licensed professional engineer in Florida.

Erin Preston

Erin Preston

General Counsel

Erin Preston represents the District as the General Counsel. Ms. Preston provides advice and counsel to the District’s Governing Board, the Executive Director and staff regarding matters of law and policy.

Ms. Preston joined the District’s Office of General Counsel in 2016. She has handled a variety of matters for the District, including permitting, contracts and procurement, human resources and complex litigation. Prior to joining the District, she was a senior trial court staff attorney for the Eighth Judicial Circuit.

Ms. Preston holds a Bachelor of Arts in Business Administration with a minor in Agricultural Law from the University of Florida. She earned a Master of Business Administration and Juris Doctorate with honors from Stetson University.

Headshot of Tom Frick

Thomas Frick

Chief Resilience Officer

Tom Frick is the St. Johns River Water Management District’s Chief Resilience Officer. He began work with the District in December 2019.

As the Chief Resilience Officer, Frick leads the District’s efforts to prepare for the environmental, physical, and economic impacts of climate change, especially sea level rise. He will work with staff within the District as well as local governments and other state agencies to develop and coordinate the implementation of comprehensive Districtwide resilience goals to mitigate and adapt to the challenges facing the District’s core missions from climate change.

Prior to joining the district, Frick was director of the Division of Environmental Assessment and Restoration at the Florida Department of Environmental Protection (DEP) for six years.

Frick began his career as an environmental scientist with the DEP Chemistry Laboratory. He has more than 27 years of experience in both the private and government sectors specializing in the areas of data collection, quality assurance, ecological assessment, interpretation of environmental data, and water body restoration. His focus during his tenure with DEP was to ensure the highest quality data, methodologies and technology to inform better environmental decisions to assess, restore and protect Florida’s unique water resources.

He holds a Bachelor of Science degree in chemistry from Florida State University.

Headshot of Sam Gardner

Sam Gardner

Inspector General

Sam Gardner joined the District as Inspector General in August 2021 with more than 24 years of government experience in Florida.

Gardner was employed earlier in his career with the Florida Division of Retirement, then with offices of inspector general at the Department of Management Services and Department of Revenue, and more recently with Florida State University (FSU) as the Northwest Regional Data Center’s (NWRDC) compliance officer. Previous work experience includes internal and compliance auditing and audit management, information systems auditing, and managing internal controls and compliance initiatives.

Gardner earned a Bachelor’s degree from the University of North Florida, Master’s degree from FSU, and holds several relevant professional certifications.