Opportunity
In June 1979, an exploratory oil well suffered a blowout in the Gulf of Mexico. The resulting oil spill was one of the largest in history.
Oil that reached the shore impacted a wide area. As the oil spill moved northward from Mexican to US waters, skimmers and booms were used to block the inlets to bays and lagoons.
Forming a passage between the Gulf of Mexico and Mesquite Bay, Cedar Bayou separated San Jose Island and Matagorda Island, two barrier islands that help protect the Aransas National Wildlife Refuge. The refuge harbors populations of alligator, armadillo, javelina, roseate spoonbill, and white-tailed deer, and offers a wintering ground for the world’s largest flock of endangered whooping cranes. Cedar Bayou itself was known as a place to catch red drum, flounder, and spotted trout.
Sand was bulldozed to block Cedar Bayou, preventing oil from entering Mesquite Bay and washing onto the shores of the wildlife refuge. However, this interrupted the exchange of Gulf waters with Mesquite Bay and prevented the eggs and larvae of fish, shrimp, and crabs from entering the bay.
Solution
Mott MacDonald was retained in 2005 to investigate the physical processes controlling the hydraulics of Cedar Bayou, and assess the feasibility of restoring the passage.
In 2011, Aransas County secured a permit from the Army Corps of Engineers for a new effort to unblock the bayou. Excavation began in April 2014, with Mott MacDonald providing expertise in design, permitting, and construction. Approximately 540,000 cubic yards (413,000 cubic meters) of material were removed with a hydraulic dredge, excavators, and off-road trucks.
On September 25, Cedar Bayou and nearby Vinson Slough were reconnected to the Gulf for the first time in 35 years. Aransas County Judge Burt Mills manned the excavator that made the final cut releasing the waters of Cedar Bayou into the Gulf of Mexico.
According to Mark Ray, board chairman of the Coastal Conservation Association (CCA), the effort was one of the biggest single infrastructure projects his organization had been involved in. “It’s a dream come true,” he said, “a $9 million gift to the Texas Coast.”
Outcome
“Now that the inlet is open,” said the South Texas TV station KII-TV, “it is great news for local fishermen and for wildlife like whooping cranes that migrate here in the winter. The bayou is called the lifeblood of the bay.”
The Corpus Christi Caller-Times quoted Jason Williams of the Harte Research Institute for Gulf of Mexico Studies as saying, “It’s going to be like a light switch. We should notice improvements almost immediately.” The paper reported, “Biologists suggest the open pass will benefit the production of shrimp, crabs, flounder, redfish and myriad organisms that make up a healthy ecosystem, including the iconic cranes, which feed on blue crabs.”
According to the CCA, “Quantifying the economic benefits of reopening Cedar Bayou is difficult but that does not suggest that the benefits are uncertain. Restoring Cedar Bayou will improve the productivity of the bay system. More fish, more crabs, and more birds mean more birders, more fishermen, more hunters and more visits by folks who love the Texas Coast. More visitors mean more business for local fuel stations, hotels, restaurants, outfitters, marinas, bait stands, sporting goods stores and the like.”