A jetty solution for safer navigation
Texas General Land Office / Port Aransas, Texas
Piper Channel, also called Mustang Beach Channel and Island Moorings Channel, provides access from the Gulf of Mexico to a subdivision and marina called Island Moorings. The channel experiences sedimentation and pressure field effects from passing vessels that cause the channel to shoal and diminishes navigation safety.
In 1996, two 800-foot geotextile tube jetties were installed at the connection of the channel with Corpus Christi Ship Channel in an attempt to reduce channel shoaling and shoreline erosion. In 2001, a 200-foot section in each jetty breached, allowing sediment to migrate into the channel. The channel was then closed.
In 2002, the Texas General Land Office retained Mott MacDonald to design a permanent solution to protect the channel entrance from erosion, sedimentation, and extreme hydrodynamic conditions that affect the safety of navigation.
The project consisted of removing all portions of the existing jetties and replacing them with a new flared jetty alignment that would reduce channel sedimentation, reduce wave energy penetration, and improve navigation safety.
Mott MacDonald performed a feasibility study, conducted engineering analysis and design, and provided engineering services during construction. The new jetty structure was composed of coated steel sheet piling, a waler system, vertical steel piles and batter (angled) piles, and navigational aids. We also designed a new shore protection system consisting of a rock revetment and an erosion control system for upland surface water runoff.
The new jetties, completed in 2007, eliminated the need for continuous maintenance dredging. The Airport and Channel Corporation retained us to monitor the performance of the structures and implement maintenance projects to prolong the life of the structures.