Degrove Completes Hydrographic/Topographic Survey at Mile Point; Supports Efforts of USACE & JAXPORT

Degrove Surveyors recently completed a Hydrographic and Topographic Survey for the U.S. Army Corps of Engineers in support of their efforts on the Mile Point Project.  Mile Point is an area located between river miles four and five west of the Atlantic Ocean along the St. Johns River, at the confluence of the river and the Intracoastal Waterway (IWW).  The IWW enters the St. Johns River from the south out of Pablo Creek at an angle almost parallel with the channel, with flow usually running in the opposite direction of the flow of the river.

These difficult crosscurrents not only cause concerns about erosion of the Mile Point shoreline, but also prevent certain large vessels from navigating this portion of the river during the ebb tide.  As a result, the problems at Mile Point present the greatest obstacle to the growth of Jacksonville’s ports.

The Corps has partnered with Jacksonville Port Authority (JAXPORT) to address these problems.  The Corps and JAXPORT recently signed the Project Design Agreement which will allow the design to move forward.  Currently, the recommended plan includes relocation and reconfiguration of the existing training wall, restoration of Great Marsh Island, and creation of a flow improvement channel in Chicopit Bay.  An illustrated presentation of these details can be viewed here.

Degrove’s services included a Hydrographic and Topographic Survey of this entire area, including the area along the training wall and rock jetties, Great Marsh Island, and large portions of Chicopit Bay.  Degrove completed the field work in less than three weeks, with as many as three crews working on it at a time.  RTK GPS was utilized for both the uplands and hydrographic portions of the project.  Hydrographic crews utilized Degrove’s 14-foot Demaree inflatable-pontoon boat.  This platform has the advantages of a very shallow draft, superior stability, and a rugged construction that allows the vessel to make contact with jetty rocks without incurring any damages.  All data was used to create a Digital Terrain Model. 

Above: Image shows coverage area of survey data that Degrove achieved for the Mile Point project.