From Bridge to Landbridge: Orleans Landbridge Shoreline Protection Project
Jerry Carroll, P.E. & Brett Geesey, P.E.
In 2010, the Louisiana Department of Transportation and Development (LaDOTD) replaced the
I-10 Twin Span bridge over Lake Pontchartrain damaged during Hurricane Katrina. Public law
requires any state which demolishes a bridge eligible for Federal assistance to first make the
debris available for beneficial use. The demolition of the bridge would yield over 200,000 tons
of reinforced concrete structural elements. Due to the Orleans Landbridge Shoreline Protection
Project (PO-36) being in close proximity to the I-10 Twin Span Demolition project, the Coastal
Protection and Restoration Authority (CPRA) coordinated with LaDOTD to obtain the bridge
material for incorporation into the design and construction of the PO-36 project.
The PO-36 project was constructed to protect approximately 8 miles of vital marsh complex
along the perimeter of Lake Borgne from Bayou Bienvenue to Alligator Point. This area is part
of the “East Orleans Landbridge” which forms a land barrier between Lake Pontchartrain and
Lake Borgne. The project is also a continuation of previous shoreline protection projects in the
Lake Borgne area, including Coastal Wetlands Planning, Protection, and Restoration Act
(CWPPRA) projects PO-30 and PO-32, and a state surplus project, Biloxi Marsh Shoreline
Protection Project PO-72. CPRA’s stated objectives for this project are to halt shoreline retreat
and marsh loss along Lake Borgne, reestablish a sustainable lake rim, restore saline marsh
habitat, and enhance fish and wildlife habitat over the specified 20-year design life.
This presentation focuses on the design and construction of a shoreline protection feature which
includes a revetment constructed of marine mattresses filled with crushed recycled concrete.
Jerry Carroll, P.E.
Coastal Protection and Restoration Authority
450 Laurel Street, Baton Rouge, Louisiana 70801
225-342-1346 – jerry.carroll@la.gov
Jerry Carroll is the Chief of the Engineering Division at the Coastal Protection and Restoration
Authority. He has been employed with CPRA for 9 ½ years, have served in his current position
for the last 1 ½ years. He possesses a degree in Civil Engineering from the University of
Louisiana – Lafayette and a degree in Geology from LSU.
Brett Geesey, P.E.
HDR Engineering, Inc.
201 Rue Iberville, Suite 115, Lafayette, Louisiana 70508
337-347-5598 – brett.geesey@hdrinc.com
Mr. Geesey is a Coastal Project Manager in HDR’s Lafayette, LA office working on coastal
restoration projects throughout the Gulf coast. Mr. Geesey’s project experience includes
shoreline protection, dredging, beach nourishment, marsh restoration/creation, numerical wave
and circulation modeling, and the evaluation of coastal processes and their structural interaction.
In particular, Brett has extensive experience working in soft soil conditions found within many
Gulf coast estuaries.