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Expanding Houston Ship Channel While Benefiting the Environment

Project Background

Houston Ship Channel Project

In 2016, a new class of ships began traversing the Panama Canal. Dubbed the Neo Panamax,” these ships reached lengths of 1,200 feet long, 168 feet wide, and up to 50-foot draft, with up to 14,000 container capacity. Shortly thereafter, these ships began transiting the Houston Ship Channel to terminals at Port Houston.

Arrival of these new ships created a problem—the channel was only wide enough for one Neo Panamax ship to pass at a time, creating delays and traffic problems. Expansion of the channel was deemed the natural solution. Port Houston is partnering with the U.S Army Corps of Engineers in Project 11 to safely and efficiently sustain national energy security and support economic growth by widening about 26 miles of the nation’s busiest waterway by 170 feet in Galveston Bay and deepening an upstream segment to 45 feet. HVJ has supported Port Houston’s commitment to environmental stewardship by using dredge material to create new features that benefit the environment.

Practice: Geotechnical Engineering

Sector: Port

Location: East Texas

Services: Slope Stability, Settlement, USACE PSDDF and SETTLE analysis

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The Problem

In 1912, the group that is known today as Port Houston began dredging work on a deep-water ship channel connecting the port to the Gulf of Mexico. The completion of this channel turned the city into an economic powerhouse, exporting vast amounts of oil, rice, cotton, and other commodities.

After a century of loss due to development and land subsidence, the vital wetlands surrounding Galveston Bay became diminished. These marshes provide a home for much of the wildlife in the area, including birds, fish, and shrimp. HVJ has supported Port Houston for over 25 years in their successful program to improve the environment through their expansion projects.

The Goal

HVJ working with Gahagan & Bryant Associates and Turner, Collie, and Braden (now AECOM) supported Port Houston to achieve three large-scale objectives:

  1. Design and implement protected bird habitats taking the form of islands located at least a mile from land to insulate threatened species from human intrusion.
  2. Replace thousands of acres of marsh that have sunk due to subsidence, restoring an important breeding ground for native fish and shrimp.
  3. Restore oyster reefs—a critical element when it comes to preventing erosion and filtering bay water —by creating a thin layer of limestone on the bay bottom and encouraging oysters to attach.

Since 1992, HVJ has demonstrated expertise in creating these habitats by using dredge materials in a beneficial way. Since then, the firm has continued to evolve its understanding of wetlands by designing marsh environments at over 15 additional sites where marsh had been lost due to development, erosion, and subsidence.

The Solution

HVJ was able to predict how to pump the watery clay into a site so that it settled at a specific elevation which is the key to successful marsh projects. Too little material would result in open water, and too much would mean that the ground is too high to support the marsh grasses that are characteristic of the biome.

By carefully analyzing how the ground settled after the clay-rich water was pumped in, HVJ was able to predict the amount of material to place at a marsh site so that the final surface was within about half a foot of elevation—the perfect conditions for creating marshland. As of this writing, HVJ has been able to repurpose dredge material from the port expansion into thousands of acres of new wetlands, while creating new habitats for the rich wildlife that forms part of the core ecosystem in the Gulf of Mexico.

Previous beneficial use projects have received the Engineering Excellence Award from the Consulting Engineers Council of Texas, the American Association of Port Authorities Environmental Enhancement Award, and the Texas Commission on Environmental Quality Clean Texas Award.

“HVJ has been the go to geotechnical engineering firm for the JV. They have continually performed complex scopes of work with expedited schedules on time and within budget in order to support the design and successful construction of beneficial use projects in Galveston Bay.”

Dana Cheney
Vice President, Gahagan & Bryant Associates

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