The ‘Ike Dike’ is the Army Corps of Engineers’ largest project ever. It may not be big enough – Grist Magazine

Excerpt:
The $30 billion barrier may fail to block climate-fueled storm surge — and won’t prevent other urban flooding in Houston.

In September 2008, Hurricane Ike made landfall near Galveston, Texas, as a Category 4 storm with around 20 feet of storm surge. Even though the hurricane caused more than $7 billion in damage, it soon became clear that the disaster could have been much worse: If the storm surge had struck the coast at a different angle, water might have funneled up the Houston ship channel and inundated the city’s all-important petrochemical hub, not to mention thousands of homes.

In the aftermath of the storm, Texas officials searched for a way to protect Houston from similar events in the future, and they soon settled on an ambitious project that came to be known as the “Ike Dike” — a chain of sea walls and artificial dunes along the 50-mile-length of Galveston Bay, anchored by a two-mile-wide concrete gate system at the mouth of the ship channel. The gate would stay open during calm weather to allow ships to enter and exit the channel, but would close during hurricanes, shielding the city and its oil infrastructure from flood events.

The Ike Dike has since become synonymous with hurricane resilience in Houston: Local officials have spent a decade lobbying for the project, and now it’s closer than ever to becoming a reality. The U.S. Army Corps of Engineers, the nation’s chief builder of levees and flood walls, secured congressional approval to move forward with the barrier last year. The $31 billion system is the largest project that the Corps has ever undertaken, with the gate system accounting for two-thirds of the cost. The agency says it will take around two decades to complete.

Despite the massive scale of the project, there’s one big problem: Experts say the Ike Dike won’t reliably protect Houston from major storms…