The $20 million U.S. Army Corps of Engineers/Texas General Land Office Coastal Texas Planning Study covered the Texas coast and examined both storm surge protection and ecosystem restoration. The report is out for public comment through Jan. 13.

The corps and land office have made a real effort to explain their outcomes to the public through visuals and interactive programs. This is a welcome addition to a now 1,000-page report that was missing in the first version. Overall, this second report is much improved and shows the results of a lot of hard work on a complex problem.

However, the design can and must be made better.

The first thing that strikes us is the poor overall performance of the corp’s design for its estimated expenditure of $26.17 billion. The plan states expected damage reduction of only 60 percent over the 50-year period of economic analysis.

The principal issue causing these large damages is a failure to hold to the coastal spine “Ike Dike” principles of strong protection at the coast and keeping water out of Galveston Bay.

The corps has used the coastal spine concept but made it weaker by not gating San Luis Pass and proposing very weak protection for the land barrier on west Galveston Island and Bolivar Peninsula.

The original Ike Dike plan first proposed in 2008 had all protection at about 17-foot height throughout the spine and gated San Luis pass. The corps plan varies considerably in height and strength of protection. The Bolivar roads gates are at 21.5-feet height and the present seawall raised to 21 feet.

But the principal coastal land barriers are two sand dunes at 12 and 14 feet. These sand dunes have effective protection much less than those heights.

The corps’ dune response modeling shows that the dunes would be below 12 feet for 75 percent to 80 percent of the time. This very weak dune component allows water into the bay during storm events and won’t hold up over the multiple years between nourishment.

Because the regional storm surge protection modeling was done assuming the dunes afforded 12 feet solid protection, the expected regional surge damages are actually greater than already poor stated results.

The other source of water into the bay is an open San Luis Pass. Not closing the pass during storm or high water events allows forerunner surge in the bay, as well as regular storm surge which directly affects structures on the West End of Galveston Island and on the mainland north side of west bay.

It also disallows sealing the bay at low tide with an approaching hurricane to reduce bay elevations as much as possible. Every contribution to water height in the bay increases the surge in the bay and thus increases the need for and strength of the bay lines of defense.

Future articles will focus on three areas of concern: natural sand dunes as designed are simply not strong enough, the need for San Luis Pass gating to reduce surge effects throughout west and Galveston Bays, and the approach to Galveston Ring Barrier protection.

William Merrell, Ph.D., is a professor at Texas A&M University at Galveston.

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(7) comments

Ted Gillis

If we get a Rita or a Katrina striking south of San Luis Pass in the near future, there will be little reason to continue with this effort, as there won't be much left standing on the west end or inland to protect. A 25' surge will put salt water past highway 6 in Santa Fe, and standing water in homes east of I 45 up past Baytown. A 25' surge will top the Seawall by several feet and top the Texas City barrier too.

I'm all for fairness and I do have environmental concerns for what these protective structures would create, but this is a plan that we need to implement now.

One more hurricane like Ike or Harvey will cause me to pack up and leave for good.

Gary Miller

Building codes requiring raising anything needing protection from storm surges may be the most cost effective. Raising the Galveston "break water" from 17 ft. to 21 ft would protect properties directly behind it but little else. The 23 ft. TC/LM storm levee has done a good job so far but was almost topped by a Cat 3 storm. With no way to remove water If topped it would worse than no levee.

George Laiacona

Let us face reality, until a storm comes along that will cripple the Oil Companies investments in Galveston and the surrounding counties, any plan will not convince government officials that funding will be made available to project Galveston Island and surrounding areas. Some how we have to get the people with the money to get on board in order fee to finance this project or any other proposal. Dr Merral is right and needs help convincing the Oil people of the advantages of coastal protection.

Gary Scoggin

Any smart operator is making the assessment of future flooding risk when deciding on investments in coastal areas. I agree that until a better flood mitigation plan is built, these companies are not going to rely on it in their analysis.

Moreover, rising sea levels and stronger storms linked to climate change only makes this issue more acute.

Ted Gillis

I agree Gary. Building slab on grade stuctures around these parts is probably going to be a thing of the past, and something insurances companies will inevitably frown upon.

Stephanie Martin

Not sold on it.

Jarvis Buckley

While some type of protection is needed from Freeport to Orange 🍊 Texas to guard our waters from possible pollutants from the the chemical chemical Plant located along our coastal water ways a one size fits all project is likely to be nicked by political resistance. Land owners along the coast property values will tumble in my opinion causing the to scream to their political representatives to vote no on this proposal. Just my thoughts.

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