Coastal Solutions

Our first article summarizes an investigative team member’s first impressions on a visit to Galveston Island, TX October 3-5, 2008. See the engineering summary and photographs of the team visit.

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Investigation Team Report – Part 1

Lesley Ewing

The coastal field investigation teams met in Galveston on the evening on October 3^rd.. The drive from Houston provided an introduction to the storm damage – several of the high rise buildings in downtown Houston had lost windows, there were damaged buildings on both sides of the highway, many boats on the side of the road as we crossed the causeway to Galveston and several trailer loads of damaged cars were being carried off island. All the out-of-town team members had been able to get hotel rooms in Moody Gardens, one of the hotels being used by the Red Cross and other volunteer groups. There was a curfew on the island from 7 PM till 6 AM and all drinking water needed to be boiled. The hotel had most services restored, but the restaurant had to close in time for the staff to leave before curfew and most people missed dinner on the first night.

Day 1

The coastal survey participants all met together for the first time on Saturday morning. We went through introductions; signed our forms that acknowledged that we were doing the survey at our own risk; had a short briefing on the hurricane, types and locations of damage reported by earlier surveys or in news stories, the various pre-event surveys and instrument deployment, and anticipated post-event surveys in addition to our effort; and, we discussed what features or locations we wanted to see.

By 9:30 we were divided into four groups and heading to the coast. Each group had loosely identified one or two things to examine – small structures, shore protection, marinas and small boat harbors, sediment transport, geomorphic features and slopes. On the first day all groups stayed on Galveston Island and headed in different directions. Two groups stayed along the gulf coast for the whole day and the other groups headed to the bay side. The gulf coast groups were joined for the first day by a Galveston resident who provided information on what the city looked like prior to Ike.

The Galveston Seawall protects most of the eastern and central gulf shoreline. At the eastern end of the island the seawall veers inland and connects to the western jetty for Galveston Bay. A large beach had built up behind the jetty and seaward of the Seawall and over the years, a number of structures had been built on the beach. Stopping near the jetty we saw rocks displaced from the top of the jetty, lots of debris on the beach and all that remained of the beach club that has been near the jetty was the slab foundation.

A small distance west of the Jetty, and still seaward of the seawall is a new community that is being built to “fortified” building standards. The buildings that were there showed signs of wave damage and flooding at the lower levels; the upper levels seemed undamaged. Construction workers were replacing the damaged drywall, paneling and flooring and landscapers were busy replanting toppled palm trees and reestablishing the beach dune.

Investigative team member Bob Dean showing maximum water level on palm tree, East Galveston

The groups stopped at several spots along the Seawall and groins. There was significant damage on all the piers and one groin had a few rocks that had been dislodged. A lot of the murals that had been painted on the seawall had been sandblasted off during the hurricane, but the wall seemed to have survived well. The investigation did not provide a thorough examination of the seawall or the substrate, but the only signs of damage or displacement were at the very west end of the seawall.

West end of Galveston Seawall

The Seawall does not extend to the western end of Galveston beach. Most of the development along the beach in west Galveston is residential development – detached homes or small townhouses and condominiums. Almost all the buildings seaward of Route 3005 (the main east-west road through the island) had loss of lower stairways and break-away walls, some had damage to the drop foundation and scour around the piles. Many communities were collecting sand from roads and under buildings, sieving it to remove large objects, and either returning it to the beach or stockpiling it for future beach nourishment.

The main objectives of the first day were to observe the types of damage that had occurred, look for and record high water marks (such as debris lines or water stains on piles or interior walls. Galveston was just west of the main hurricane track. There was a lot of flood damage in the bay side of the island and in low lying areas without any shore protection. Wind damage and debris were observed throughout the island. A temporary debris center had been set up near the airport and by the time of our visit, it contained enormous mounds of debris and throughout our visit in Galveston, we saw truck after truck going to the yard to dispose of collected trash.

Geotubes rotated seaward, West Galveston

Homes on Shoreline, Piles toppled seaward, West Galveston

Day 2

The second survey day started at 5:15AM with a long drive east to Bolivar Peninsula and main survey ended when we all met on the 6 PM ferry back to Galveston. Like Galveston, Bolivar had a curfew. We were only allowed on the island between 6 AM and 4 PM and were asked to start leaving the island by 2 PM. The ferry from Galveston to Bolivar normally runs throughout the day, taking about 20 minutes to cross the Bay. Since we were not sure whether or not we could use the ferry, we drove 90 miles to get into the peninsula at High Island near Rollover Pass. Many of the businesses in central Galveston had been cleaned up and were either beginning to reopen or in the midst of repairs. Damage on Bolivar was far more extensive than on Galveston and property owners were in the early stages of site clean-up. We spoke with some people who were cleaning up their properties and were told that the County has imposed a 120 day moratorium on rebuilding – still need to check with the County to see if this is true. Several of the beach-side property owners are reclaiming “their sand” from inland lots. Most utilities to and on Bolivar had been damaged and electric crews from around the country has come to Texas to help replace poles and string line.

Several sections of beach had been protected by geotubes. The geotube system consisted of an apron foundation with a center mat for the geotube and small cells on the seaward and inland sides of the tube to prevent it from moving off the apron. The apron and geotube system was between about 2 to 2.5 meters high. Some geotubes remained in place, but many of the geotube structures had rotated off the apron. Most had rotated seaward, likely from scour under the apron. A few geotubes had rolled inland and deflated. The geotubes may have reduced some erosion and inland flooding, but some local residents said that they left their homes when they saw that the water was more than half way up the geotube and rising quickly.

Homes, Bolivar Peninsula

The third survey day we went to some small craft harbors, marinas, the San Luis Pass, and bay-side developments. More on this later.

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