Seawater Intrusion and
Coastal Aquifer Vulnerability
A one-day decision-maker workshop exploring the current state of coastal aquifers, the vulnerability of
coastal aquifers to seawater intrusion, gaps in necessary data regarding vulnerability and development
of better management tools.
Date: Tuesday May 29, 2012
Times: 9:00am to 3:00pm (Lunch Provided)
Location: Weeks Bay Reserve Resource Center, US 98 between Fairhope and Foley, Alabama
Objectives:
1) Audience can identify seawater intrusion patterns based on status of coastal aquifers and based
on current and projected use patterns.
2) Audience can identify aquifers vulnerable to seawater intrusion.
3) Audience can list gaps in data regarding aquifer vulnerability to seawater intrusion.
4) Audience can identify strategies to better prevent seawater intrusion.
Draft Agenda
9:00am - 9:15am
Welcome
9:15am- 10:15am
Current Water Quantity and Quality in Coastal Aquifers (S. Baldwin
County, AL)
1) Hydrogeology, Stratigraphy, LULC Change/Impacts, Water Quantity,
Recharge
 recharge estimate for water quantity (to be conducted)
2) Water Quality; Chloride and Nitrate Data (Extent and Source)
 chloride and nitrate data (the extent of contamination and source
identification)
10:15am - 10:45am Current and Projected Use Patterns and Vulnerability [ADECA/OWR]
3) Water Demand, Consumption, Water Use [Tom]
 use patterns now and in the future based on best available estimates
 projected use patterns
10:45am - 10:50am Break
10:50am - 11:45am Current and Projected Vulnerability [Geoff/Dorina]
4) Water Use Impacts on Seawater Intrusion and Aquifer Vulnerability under
Current and Projected Use patterns [Geoff/Dorina]
 seawater intrusion geochemical assessment
 vulnerability assessments using isotope and geochemistry forensic analysis;
delineation of recharge areas
 the 2000 vulnerability study (stratigraphic and geochemical vulnerability
assessment)-Area 13
 cross-sectional model showing nitrate transport to coastal waters
 LULC change evaluations
 If all current production is north of the Intracoastal Waterway, is there a
problem? What is the impact of the IW?
11:45am - 1:00pm
Lunch Provided
1:00pm - 2:00pm
Management Strategies, Optimization, Reduced Vulnerability [UA, GSA,
ADECA/OWR, ADCNR]
1) SWTGA: Study Results, Applicability and Use by Water Resource
Managers/Regulators [Geoff]
2) SWTGA: Optimized Management Scenarios [Geoff]
 well placement, pumping options, LULC
3) Development Management Strategies Reduce Vulnerability [Geoff/Dorina,
Marlon, Tom]
 activities that take place on the land surface: tight coupling between land use
decisions and groundwater resource management decisions
 methods and evaluation strategies to determine water management options that
are balanced with the commercial, industrial, agricultural, and community
design directions
2:00pm - 3:00pm
Basic Facilitated Discussion of Data Gaps Regarding Aquifer Vulnerability
[GSA, ADECA/OWR, ADCNR, UA]
 Data availability in area south of the Intracoastal Waterway (limited by the
absence of sampling sites for the deeper aquifers)
 Time series investigations to determine the response to different aquifer
stresses (increased pumping); potential for aquifer recovery
 Water use for large-scale irrigation
 How much actual field data was used in the modeling and how much is
needed?
 Lack of field data.
 Misunderstanding of the hydraulics and hydrogeology of the system.
 Unrealistic result of modeling.
Format:
2) Lecture
3) Q/A
75%
25%
Workshop Sponsors:
Alabama Department of Conservation and Natural Resources, State Lands Division, Coastal
Section; Geological Survey of Alabama; University of Alabama, Department of Geological
Sciences; Alabama Department of Economic and Community Affairs; Coastal Training Program of
the Weeks Bay National Estuarine Research Reserve; Baldwin County Soil and Water
Conservation District; National Oceanic and Atmospheric Administration and Weeks Bay Reserve
Volunteers.
Funding for this project was provided in part by Award No. NA08NOS4190462 through the Coastal Zone Management Act
of 1972 (as amended), administered by the Office of Ocean and Coastal Resource Management, National Oceanic and
Atmospheric Administration and in conjunction with the Alabama Department of Conservation and Natural Resources,
State Lands Division. The Weeks Bay National Estuarine Research Reserve is a component of the National Estuarine
Research Reserve System established by Section 315 of the Coastal Zone Management Act, as amended, and funded by the
Alabama Department of Conservation and Natural Resources, Lands Division, Coastal Section, in part, by a grant from the
National Oceanic and Atmospheric Administration, Office of Ocean and Coastal Resource Management.