Presently, GBA is the largest engineering firm in the United States specializing in dredging and marine related projects. With offices in Philadelphia (PA), Wilmington (DE), Baltimore (MD), Wilmington (NC), Tampa (FL), Houston (TX), Los Angeles (CA) and San Francisco (CA), GBA is strategically located to meet each client’s needs. GBA of NC, PLLC maintains an office in Wilmington, NC to provide engineering services in North Carolina.

Navigational Channel Design

GBA is actively involved in designing ship channels, turning basins, and berthing areas throughout the United States.

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Dredging Engineering

GBA approaches the solution to a dredging need based on its extensive experience as a major dredging contractor.

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Beneficial Use of Dredged Material

GBA is on the forefront of developing beneficial uses for dredged material through environmental restoration.

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Agency Coordination

When working with the U.S. Army Corps of Engineers (USACE), GBA helps state and local agency clients save both time and money.

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Hydrographic Surveys

GBA is a pioneer in the field of hydrographic surveying and has a broad range of experience and background surveying for every major port in the U.S.

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Coastal Engineering

GBA has extensive experience in beach nourishment, wetland creation/restoration, artificial reef construction, shore protection, structural design and more.

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Construction Management

Our inspection services cover all phases of construction from dredge operations to the final placement of the dredged materials as landfill and more.

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Witt Barlow - Senior Executive Vice President

Witt Barlow has 39 years of experience in the dredging industry. As former president of the largest U.S. dredging company, Great Lakes Dredge & Dock Company (GLDD), and former owner and CEO of B+B Dredging. He has direct knowledge of all aspects that go into the dredging contractor’s analysis and ultimate bid for a project and in project execution. He is instrumental in developing cost estimates that are correct and clearly defendable during the federal coordination and has extensive experience in construction management utilizing every dredge type.

Frank Lowell Hamons - Senior Associate

Frank Hamons joined the Company as a Senior Associate in November, 2013. Prior to that he developed and directed the Maryland Port Administration’s Dredged Material Management Program for 33 years, gaining executive level port management experience in long range planning, feasibility studies, channel system design, modification and maintenance, placement facilities selection, construction and operation, innovative reuse of dredged material and public outreach and involvement. He has 13 years’ experience in natural resources management ranging from shellfish management and propagation to watershed planning, monitoring and management. He earned a B.A. in Liberal Arts with a Major in Biological Sciences, Ecology from Frostburg State College – 1966.

Bob Callegari - Vice President

Bob Callegari has over 43 years of experience working in the areas of navigation planning, coastal planning and analysis, dredging and dredge material management and beneficial use of dredged materials. He worked in the Corps of Engineers for 31 years, the last 14 of which he was Chief of Planning for the USACE Philadelphia District. In this capacity, Bob Callegari was responsible for developing the analyses that were the basis for the construction authorization of over $3 Billion dollars in projects, ranging from deep draft navigation to flood control to environmental restoration. Since leaving the USACE, he has worked on a variety of policy, economic, and engineering issues dealing primarily with deep draft navigation dredge material disposal and management as well as beneficial use of dredged material. He currently heads GBA’s efforts to assist the Philadelphia Regional Port Authority in the implementation of the deepening of the Delaware River Main Channel to 45’.

Stan Lulewicz - Senior Associate

Stan Lulewicz joined Gahagan & Bryant Associates in 2006 as a senior engineer. From 1973 - 2006, he was employed by the Philadelphia District U.S. Army Corps of Engineers (USACE). He has over 30 years of project management experience with large-scale feasibility and pre-construction engineering and design water resource studies/projects. He has managed studies/projects from inception to design and construction involving deep-draft navigation, coastal and marine shore protection, flood control, and environmental mitigation. He is very familiar with USACE Section 10/404 permitting; Dredged Material Management Plans; Environmental Impact Statements and Environmental Assessments in compliance with National Environmental Policy Act, Clean Water Act, Coastal Zone Management. He is a Professional Engineer in the State of New Jersey, New York, Delaware, Pennsylvania, and Maryland. He is responsible for providing, engineering, hydrographic surveys and consulting services to clients on dredging, environmental assessments, permitting and construction requirements, geotechnical investigations & analysis, preparation and review of plans & specifications and project construction. He earned a Bachelor of Science Degree in Civil Engineering from Villanova University and Master of Science Degree in Civil Engineering from Drexel University.

Douglas C. Moore - Survey Division Manager (PLS) (CIH)

Doug Moore joined Gahagan & Bryant in 2003 as Survey Division Manager. He was previously employed by the Philadelphia District U.S. Army Corps of Engineers from 1965 until 2003, when he retired as Chief of the Survey Section. He is a Professional Land Surveyor licensed in the State of New Jersey and a Nationally Certified Hydrographer. He was selected to the U.S. Army Corps of Engineers Distinguished Gallery of Employees in 2005 and inducted into The Hydrographic Society Hall of Fame in 2013.