Galveston’s Strategic Retreat by Ted Eubanks

Conservation, Politics, Sustainability, ,

The brouhaha over the buyout of beach front dwellings has flamed into an inferno. Many demand that the Hazard Mitigation Grant Program money be spent in less affluent neighborhoods in the central city, repairing homes that may well attract residents back to the city. Heber Taylor, editor of the GCDN, has argued this case repeatedly and effectively. As recently as today Heber is bemoaning the fact that West Enders are getting a sweet deal on their homes.

There is merit to both arguments, I believe. I live in the central city, and I would love to see hazard mitigation money be used to redevelop the contracting neighborhoods that surround me. But I also see how a strategic buyout on the west end offers an opportunity to address our flood risks in a unique fashion. To be honest, One Galveston should address both of these issues, no matter income levels or geographical location,.

For the moment let me focus on the west end. In recent weeks there has been a push for Galveston to consider armoring the entire length of the west end of the island. This “Ike Dike” would connect with a series of retractable or collapsible flood gates at Bolivar Roads, San Luis Pass, and across the GIWW. Even though the cost of such a massive project would be many billions of dollars, there has been little critical debate concerning its merits (like, would it work?). Galveston’s mayor and the county judge have already sped ahead with lobbying for this approach without critical analysis (or thought). If we are going to spend billions on such a massive structure, shouldn’t we at least know that it is not a Maginot Line?

During my past week’s recovery, I have had the chance to spend several days reviewing the literature (the only side benefit of being stuck in a hospital with a laptop). A review of the science, I found, should give us pause. Hardened or armored coasts are among the most significant causes of the loss (not gain) of beaches. In fact, Galveston’s seawall is often identified as the classic example (the beach having disappeared by 1916). Any “Ike Dike” would require continuous beach replenishment, a cost for which a source has yet to be identified (perhaps to be funded by beach front property owners?) The debate over who should pay for beach renourishment has been a point of contention around the country for decades, with many citizens objecting to being taxed to fund sand that benefits only a few.

There is an alternative to armoring the coast – a manageable or strategic retreat. In this scenario development is removed from the beach and the natural dune system is allowed to restore. In the case of west Galveston Island, the funds available for buyouts would be used to remove all beach front dwellings. Beach renourishment would still be necessary to stabilize the shore slope (the Bruun Rule), but a broad beach with an extensive dune structure would provide a buffer against all but the most severe storms. Since dune building is generally an aeolian (wind driven) process, I suspect that it would also be necessary to restrict vehicular traffic along the beaches to avoid compaction.

The same strategy of managed retreat would be necessary along the bay shore as well. Housing development should retreat to the upland properties that form the ridge of the island. The coastal wetlands should then be restored, and near shore boat traffic restricted, decreasing turbidity and allowing the once-prevalent sea grass beds to regenerate. Beach replenishment along the bay could come in the form of beneficial use of spoil from the dredging of the GIWW to extend the bay shore outward. In other words, a combination of beach replenishment and bay shore restoration with spoil would serve to widen the island and protect development in the interior.

The ultimate goal, of course, is to restore the natural buffers that once protected this island. With elevated housing limited to the interior, development can continue with limited risk. Natural beaches and wetlands will have been restored, offering residents recreational and aesthetic benefits that far exceed those available today. Significant efforts to rebuild a broad dune structure may well function in tandem with the planned flood gates at the ends of the island. In other words, Galveston may well be able to develop a cutting edge flood protection system where a majority of the structure is a restored natural system of protective dunes and wetlands.

No one is lobbying for a massive taking of property. Such a program could be accomplished by willing sellers selling to willing buyers (the government). This program would also require that the city planning department develop a progressive Comprehensive Development Plan, backed by council passing forceful rules and restrictions to insure the implementation of the plan. Of critical importance would be for rules that would disallow any new development in these buffer areas.

Today Secretary of State Hillary Clinton stated that “the time for action and realism is now” when facing the challenges of global warming. The same is true for Galveston and sea-level rise. We simply can no longer afford to blithely stumble forward, pretending that the forces of global climate change will somehow overlook our small sliver of sand.

In conclusion, the following is a summary from a study by Western Carolina University that speaks volumes to these very issues.


To reverse our losses, we must learn how to retreat from the shoreline. Where development already confronts the ocean, we must adopt corrective measures that are sure and fair. Where beaches are relatively undeveloped, we must apply preventive measures. A commitment to retreat as a guide to public policy and private investment would achieve the following goals:

  1. Reduce the loss of property and lives by replacing present high risk development with stable, safe development in suitable locations away from the open beaches.
  2. Meet increasing demand for public beaches by improving public access to natural beaches.
  3. Develop a more stable economic future for coastal communities.
  4. Eliminate unessential government spending and move coastal investment closer to a marketplace mechanism where economic decisions include realistic risk and cost without the benefit of direct or indirect government subsidies.
  5. Facilitate removal of many of the defensive structures and developments that now magnify the effects of erosion and the costs of disasters.

Stopping Erosion by Dr. John Anderson

Conservation, Sustainability, ,

Yesterday, Saturday January 24th, my wife Doris and I attended the town hall meeting at Sea Isle and wandered around the various booths reading the comments posted for each group. At the Environment Booth I was struck by one comment in particular that read “Stop Erosion”, which provoked me to sit down and write up this summary of the problem. Stopping beach erosion is about as complicated as stopping volcanoes from erupting and earthquakes from quaking and the sooner we accept this reality the sooner we will get on with the business of sustainable development in Galveston. I welcome questions and comments and am happy to provide scientific documentation of the statements I have made in this summary.

  1. For those who would question the importance of sea-level rise in controlling coastal retreat (erosion), consider that in the past 17,000 years, since the last major glaciation, sea-level has risen approximately 100 meters causing the shoreline to retreat approximately 80 miles from it previous location at the edge of the continental shelf to its current location.


  2. The current rate of shoreline retreat, which averages 3 feet/year along the west end of the island but in places is as much as 10 feet/year, is slow compared to times in the past when sea level was rising at a more rapid rate, at times as much as 50 feet/yr.
  3. The rate of rise in any given location is combination of eustasy (global sea level rise) and subsidence. This is called relative sea-level rise. Eustasy is fairly constant across the northern Gulf of Mexico but subsidence is highly variable. In western Louisiana the rate of subsidence is in places as much as 30 times faster than the rate of eustatic rise. Our neighbors to the east are already contending with problems that we will face by the end of this century. The rate of subsidence in Texas is significantly lower but locally is still a major contributor to shoreline change. Unfortunately, we have relatively few locations where elevation changes are being monitored and those are not all in the most ideal locations. There are ways to acquire long-term subsidence measurements but little work has been done in the field. Remember, we spend all our money in Texas dumping sand on the beach and pitifully little goes to address the real issues of why the coast is changing. If we don’t know why, we can’t begin address the problem.
  4. Sediment supply is as important as sea-level rise in controlling coastal change. If sediment is added to the coast fast enough to keep up with the rate of sea-level rise the shoreline will remain stable and even grow. This is how Galveston Island formed at a time when sea level was rising and why beaches adjacent to the north and south jetties have grown since the jetties were constructed. Sediment supply to the upper Texas coast is minimal. So, even a slow rise in sea level results in shoreline retreat. We still do not have an accurate sediment budget for the upper Texas coast. The recent study by the Corps of Engineers was a poor attempt to quantify the sediment budget and until the budget is improved it will not be possible to predict the response of the Gulf and Bay shorelines to accelerated sea-level rise. I have a PhD student, Davin Wallace, who is currently working on a more accurate sediment budget for the Texas coast.
  5. Many of the current maps that show coastal inundation through time are highly inaccurate because they simply flood the landscape with different scenarios for sea level rise. They do not account for subsidence or sediment supply. For the most part, they are best-case scenarios.
  6. The current Galveston Island Geohazard Map is a more accurate approach to predicting coastal change because it relies on historical rates of shoreline change to predict future change. However, it assumes a constant rate of sea level rise and does not take into account changes in sediment supply through time. Neither does it account for the impact of hurricanes. So, it is a best-case scenario and should be immediately adopted by the city until we have a better handle on subsidence and the sediment budget.
  7. Eustasy is controlled by the temperature of the oceans (remember water expands when heated) and the contribution from glaciers and ice sheets. There is no question but that the oceans are getting warmer as the atmosphere warms, and this is the main contributor to the current acceleration in sea-level rise. In addition, 80% of the glaciers on Earth are melting. The net result is that the rate of sea-level rise has nearly doubled (from an average of 1.8 mm/yr to nearly 3.0 mm/yr) this century. The contribution of ice sheets to sea-level rise is the greatest uncertainty when it comes to predicting future rise, but it is by far the most important in terms of magnitude. If the Antarctic Ice Sheet were to melt global sea level would rise 60 meters (~200 feet). While this is not going to happen in the next few tens of millions of years, the most current scientific evidence suggests that the West Antarctic and Greenland ice sheets are going to contribute to sea-level rise this century. At the most recent meeting of the American Geophysical Union in San Francisco one of the keynote speakers at the meeting (Dr. Eric Rignot) summarized the current scientific information on ice sheet mass balance and concluded that global sea-level rise will likely reach 5 mm/yr by the end of this century. Dr. Rignot is one of the best, most respected scientists in the field and I see no scientific justification to doubt his predictions.
  8. Let’s put Dr. Rignot’s sea-level prediction into perspective. If we want to view the world of coastal change at a time when sea level was last rising at a rate of 5 mm/yr we have to turn back our geological clocks 7,000 years. I have spent the past three decades studying the evolution of the Texas coast before and after 7,000 years. Take it from me, this was a time when our coast, including estuaries, was changing at a rate most people cannot (don’t want to) imagine. This is not science fiction, this scientific consensus based on the peer-reviewed literature. This is why we have to fight to educate people about the seriousness of the situation. We can no longer tolerate ignorance, indifference and greed on the part of those who control the destiny of our coast. We owe it to our children and grandchildren to fight for a more sustainable coast.

For additional reading consult Dr. Eric Rignot’s research.

John Anderson

Maurice Ewing Professor of Oceanography

Department of Earth Sciences

Rice University

Houston, Texas 77251-1892

Recovery Galveston – A Warning

Conservation, Politics, Sustainability,

The new Recovery Galveston website is now functioning. This is a joint effort of Lee Roane’s Galveston.com and Dolph Tillotson’s Galveston County Daily News. Potentially this is an excellent resource for the LTCRC, yet I am concerned about the signficant gaps in the information required in order for the LTCRC (and the community) to make informed decisions about our future. I realize that this is early in the process, but given the tight schedule there is little time to waste.

Let me give two examples. Two of the reports posted on the website are as much pitch pieces as information resources. The tourism analysis, by AngelouEconomics (a firm that apparently specializes in helping communities attract high-tech industries), argues in favor of beach renourishment, continued support of events such as the Lone Star Rally, and the need for more state funds to support the traditional tourism industry (in other words, the Parks Board agenda). Interestingly, the report admits that ecotourism represents 7.9% of our visitors (double those that come for conventions and cultural activities), and that the revenues from ecotourism (which the firm seems to have a poor grasp of) amounts to 7.5% of direct spending (triple that from cultural events). However, there is not a single recommendation or mention of existing nature tourism venues (such as the need to quickly restore GISP) or the organizations such as GINTC that are already working in this field. Featherfest is nowhere mentioned in the report (although Dickens, Lonestar Rally, etc. are dealt with in detail). In truth, little that they have assessed or addressed remotely reflects a sustainable tourism sensitivity.

The second report, Texas Rebounds, is a report from the Governor’s office that details the damage to various aspects of the Galveston economy and society. Interestingly, the report says little about environmental impacts other than those on the commercial fishery and forestry.

The LTCRC needs to have input from a wide variety of information sources, not only those filtered by city staff. Therefore I am requesting that there be a link to One Galveston so that the the committee can take advantage of the information provided here (such as the links to the various sources of information about sea-level rise).

The new LTCRC website is now available for the public to review. My advice is to keep a very close eye on what is being posted there. Everyone is contributing with the best of intentions, but I also believe that it is better safe than sorry.

Ted Eubanks

New Report Raises Spector of Sea Level Rise

Research

A new report issued by US federal agencies, including the US EPA and the US Geological Survey, estimates that sea levels will rise higher than estimated as recently as 2007. The new report concludes that Florida and Louisiana are the states most vulnerable to sea-level rise, followed by North Carolina and Texas. The report presents three scenarios for sea-level rise by 2100: a rise of about 16 inches, of about 2 feet, and of about 3 feet. The report notes that if sea level should rise more than three feet during the 21st century (the worst-case scenario), “it is likely that some barrier islands in this region will cross a threshold” destabilizing and breaking apart.

Galveston is currently considering how to resurrect itself from the unimaginable destruction of Hurricane Ike (the worst natural disaster, in terms of damage, in Texas history and the third worst in U.S. history). The new Long-Term Community Recovery Committee (LTCRC) has integrated “sustainability” into its considerations, but I wonder if meeting the challenges of sea-level rise is among those issues being considered. To be blunt, how can it be avoided?

Concurrently, the USACE is considering several new development projects on the west end of Galveston Island (in truth, pre-Ike holdovers). The most recent (Marquette) has apparently ignored the impacts of Ike in its resubmission. Not only must the damage wrought by Ike be considered in any new development proposal and permit (how can we add insult to injury as the Bay is still healing?), but the USACE must also consider the impacts of the 2-to-3 foot rise of sea level within the foreseeable future. We can only hope that the new administration, with its clear commitment to new U.S. leadership in meeting the challenges of global warming, will extend this commitment to how its agencies, specifically the USACE, oversee the permitting of proposed coastal developments.

Ted Eubanks

For more information about the impacts of sea-level rise on Galveston Island, read the following:

Final Report – Abrupt Climate Change (US Geological Survey et. al)

EPA Global Warming Website

Living with Geohazards on Galveston Island: A Preliminary Report with Recommendations (Gibeaut, Anderson, and Dellapenna)

Coastal Geomorphic Responses to Sea Level Rise: Galveston Bay, Texas (Leatherman – PDF)

Modeling Future Changes in Barrier-Island Wetlands on Galveston Island, Texas (Gibeaut)

Hurricane Impact Map [prepared] for Galveston City Hall, Galveston, Texas (PC Weather Products, Inc.)

Coastal Erosion, Global Sea-Level Rise, and the Loss of Sand Dune Plant Habitats (Feagan, Sherman, and Grant)

How Will Climate Change Affect Transportation Decisions – The Gulf Coast Study (American Meteorological Association)

Look at Past Sea-Level Rise Points to Troubling Future (Anderson et.al)

Changes in Barrier Island Environments During Sea-Level Rise (PPT by Gibeaut)

National Assessment of Vulnerability to Sea-Level Rise (USGS)

Global Warming Risks for Texas (Environmental Defense Fund)

Summary of Coastal Program Initiatives that Address Sea-Level Rise as a result of Gobal Climate Change [according to this report (Feb 2008] “at this time the Texas Coastal Program does not have sea-level-rise policies or initiatives specific to climate change.”]

Florida Tool Box for Coastal Planning

OCEN 400 Environmental Sustainability PPT (beach alternatives)

Beach Preservation and Stratetic Retreat (West Carolina University)

Responding to Global Warming Along The US Coast (USEPA)

Local Population Impacts and Mitigation of Sea Level Rise

Wintering Warblers – A Warning

Conservation, Research,

In year’s past Yellow Warblers were exceedingly uncommon in Texas in the winter season. There would always be that odd one or two in the extreme lower Rio Grande Valley, but by in large they were absent until returning in the spring. Of course there are those warbler species that winter here at the northern fringe of their wintering range (Black-and-white, Black-throated Green, Wilson’s, Ovenbird, Northern Waterthrush), but Yellow, for the most past, has not been among this group.

In the past several years this has changed. Now Yellow is being seen regularly in winter as far north as the Coastal Bend (see Ebird map). This year there have been several along the central coast, including one in Port Aransas at the Turnbull Birding Center and four at Hans Suter Park in Corpus Christi. There have also been several Rose-breasted Grosbeaks, with one seen as far north as Galveston. So what gives?

As most CBC participants are aware, there are good years and there are bad years. There are years when there are volumes of lingering migrants, and there are years when you couldn’t buy one. But when we look across the vagaries of these annual fluctuations, it does appear as though there are increasing numbers of neotropical migrants that are short-stopping their flights to the tropics to spend the winter season along our coast.

The difficulty with assessing the concepts of global warming as applied (not theorized) is in finding tangible evidence of its impacts. Sea level rise in Texas? No problem. Melting ice shelves and glaciers? Got ’em. Rising mortality in coniferous (boreal) forests? No doubt. But what about these seemingly insignificant scraps of evidence such as lingering neotropical migrants or tropical species (Couch’s Kingbird, Green Jay, Greater Kiskadee, Clay-colored Thrush) pushing north? Aren’t these just as important in piecing together the global effects of temperature changes?

Texas is on the frontier of this work. By being positioned at the doorstep of the tropics, slight changes in northern ranges in bird species are felt here first. This is precisely why it is critical to collect as much information on these wintering birds as possible, including being sure that the data related to these sightings are entered into a repository such as eBird. Yes, it is great fun to find a rarity out of season (such as the recent Swainson’s Thrush). But this find may also provide evidence of a much more significant change afoot, one that will ultimately impact us all, feathered or not.

Of course you can contribute to piecing this puzzle together. Enter your sightings, not matter how brief or (to you) insignificant into Texas eBird. The combined efforts of thousands of birders are critical to documenting these changes at the landscape scale. Spend the time necessary to correctly document and identify these lingerers (isn’t it amazing how many species one can turn an Orange-crowned Warbler into?). Finally, follow these lingering neotrops throughout the season. Some are late fall migrants, but many are true winter residents. The trends in those that actually remain here for the entire winter could be a critical study.