LIDAR Magazine

C’est la Vie

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Louisiana is a place of hospitality, and joviality, as evidenced by bals de maison, fais do-do, cochon du lait, carnival, and more. The embrace of welcome is the norm in this oft-misunderstood region. Late one Sunday night in August 2005 a lady named Katrina paid a visit and repaid that hospitality with an unbelievable mess. Only a few Sundays later, another lady named Rita paid a similar visit leaving behind a similar hangover. It was a year of records. Hurricane Katrina was the strongest hurricane ever recorded in the Gulf of Mexico. Less than a month later Hurricane Rita took that record for herself. The devastation of nature’s one-two punch was a near knock-out for this relatively small state of almost 52,000 square miles and nearly 2.5 million people. However, Louisiana and Louisianans are resilient.

Louisiana has 64 parishes. Following the storms, dozens of them had significant damages. Today, nearly a year later, a half dozen, for all practical purposes, are still shut down. Many folks "on the ground" have too much spirit to throw in the towel, but they face daunting odds for a semblance of normalcy any time soon. Emergency systems were overwhelmed. Bureaucratic idiocy, usually a mere nuisance, took its toll in lives and property. Governmental houses of cards are still strewn on the table; each card is waiting for the other to act before it will or can act. There are significant changes in these communities.

Predictably, those who practice surveying have seen changes in their practices as well. The situation wasn’t created overnight. The storms were simply the catalysts that accelerated or exposed the changes.

Modern Louisiana took shape over 8,000 years with the help of the Mississippi River. Draining most of North America from the Great Lakes in the north to the Gulf of Mexico in the south, and from the Rockies in the west to the Appalachians in the east, the Mississippi with its tributaries, (particularly the Ohio and Missouri Rivers) deposited sediment that resulted in the Pelican State. The southern portion consists of 70,000 feet of sedimentary material, the weight of which loads the crust causing it to bend downward. The huge pile of material also develops faults and slides with remarkable dynamism. The material de-waters and then compacts and is, historically, replenished by more sediment and the process continues. The resultant delta supports prolific flora and fauna that, when it decays, adds to the sediment. Its natural process is to deposit and grow sediment, compact, bend and fracture downward — to subside. The result is South Louisiana, a shallow plain sloping to the Gulf of Mexico.

Everything in Louisiana, including surveying, is the result of, or in response to, these facts of nature. Efforts to protect human investment along the river and elsewhere with levees and "improved" drainage disrupt part of this process with the notorious result of significant subsidence. Subsidence in South Louisiana varies from one-half inch to more than two inches per year! It is exacerbated inside those areas protected by levees.

When asked, "What has changed since the storms?" surveyors respond differently, depending on where they practice. Of universal notice by those who’ve been to the hard hit coastal parishes is the eerie silence no sounds of traffic, children playing, construction, or music. In a part of the world renowned for music and joviality, the stillness is disorienting.

Immediately following the storms, government agencies called in firms to survey various aspects of the damage. Often local surveyors were dismayed to see out-of-state license plates and unfamiliar company names on crew trucks measuring high water lines and providing other services, especially if the local surveyors were lacking work.

David Patterson, President of Louisiana Society of Professional Surveyors (LSPS) responded, saying that today most surveyors are now overwhelmed with new work, many to the point of becoming choosy about what jobs they accept. Parishes just north of the worst hit areas are booming with new construction. Baton Rouge has kept about a 25% increase in population since the storms. James Webb of Calcasieu Parish says there are "no workers available in southwest Louisiana. [just] getting away [for a day is] a chore." Surveyors who work offshore, like T. Baker Smith and Sons, report plenty of work locating damaged and submerged oilfield and maritime structures on the bottom of the Gulf.

Steve Estopinal of St. Bernard Parish said he, like some others hard hit, is closing his business. He now works for CSRS, Inc. in East Baton Rouge Parish. Estopinal Surveying & Engineering, Inc. was once the only surveying company in St. Bernard Parish. "The government may still be operating but there are no clients left there to hire you," he says. This can be true in several other parishes as well; Plaquemines, Cameron, Vermillion, for example. Where have the people gone? They’ve gone to wherever they could find places to live and work and go to school after fleeing the storm. Why haven’t they returned? Because of the bureaucratic house of cards. Many want to rebuild. The banks want to lend them the money to build, but not without flood insurance. The Flood Plain Administrators want to provide flood maps, but publication has been delayed to study the post-storms data. The flood maps are based in part on the fitness of levees and pumps, and the Corps of Engineers needs significantly more money to meet their charge. The surveyors would like to stake elevations, but there are practically no valid NGS benchmarks. People want to rebuild. The bank wants to lend … ad nauseam.

In the August 2001 Report to Congress, NGS, noting unaccounted subsidence, reported "Most of the vertical elevations (heights) used by surveyors and engineers have not been calibrated, or checked since 1988 and may currently be in error of one foot or more." In the interim, the Louisiana Spatial Reference Center was established at the Louisiana State University Center for GeoInformatics. Research at the LSU C4G on bench mark behavior resulted in NOAA Technical Report 50 and provided the data that permitted NGS to validate 85 bench marks along the southern portion of the state. Surveyors were temporarily excited to have some bench marks but quickly came to realize that with the cited subsidence rates most of the marks would become stale quickly.

Another significant change was first illustrated in the terms used by the U.S. Army Corps of Engineers to describe how the levees would be rehabilitated. The point in time was very specific. Some months after the storms, ViceAdmiral Thad Allen called a town hallstyle meeting of agencies involved with hurricane response and recovery and state and local officials in New Orleans. At the beginning, and up to the point of the meeting the phrase used was, "We will rebuild the levees to pre-Katrina heights." During the meeting, the Admiral demanded a uniform understanding of the seemingly innocuous terms elevate and elevation. After the discussion, a subtle change could be noted. The phrase became, "We will rebuild the levees to their authorized heights."

Because of the subsidence, the heights of levees above the surrounding ground would have to be significantly more than originally constructed to result in the authorized height (typically 16 ft.). Recent announcements that the Corps could rehabilitate the levees for $4.1 billion (except in Plaquemines Parish), enabled FEMA to release Federal Flood Advisories. In these areas the advisories require base flood elevations three or more feet higher than the older requirements. For some this will mean selling their property and for others it means they now know one more requirement for rebuilding.

LSU C4G has set up a network of CORS in Louisiana known as GULFNet. The network needs only a few additional stations to complete coverage at a 75-km spacing (similar to the National CORS density). The needs of Louisiana and her surveyors are greater than that. LSU C4G hopes to provide 35 km spacing. This should provide a robust, redundant, uniform, reference network across the state, allowing coordination of projects in any part of the state to any other part. Agencies such as the Louisiana Department of Natural Resources have spent years and millions of dollars, trying to relate their projects together without success, through traditional bench marks and normal quick-field procedures. The state, especially in the southern portion, has very little vertical relief, so the accuracy needs to be extraordinary. On top of that, subsidence varies from place to place and over time. CORS technology comes at precisely the right time. As the ground subsides, GULFNet will make the ideal reference. With positions calculated daily and adjusted every three days they provide timely and correct 21st century quality version bench marks.

The attitude and practices of surveyors regarding elevations have changed as well. Ever since the NGS report to Congress, most surveyors providing base flood elevation certificates have used what was assumed to be most correct the latest published elevations for the bench marks. But NGS declared them unreliable. Perhaps that declaration was the latest publication. The usual expectation was that NGS will shortly update them and we’ll be home free. After the storms, many surveyors were understandably upset. Bench marks they’ve trusted are now well known to be unreliable. Their clients wanted flood certificates, but the maps were mapped onto NGVD 1929, yet FEMA wanted reports to indicate the latest, best data which is NAVD 1988. Meanwhile, conflicting rumors abound as to what elevations to actually use.

Most surveyors are now either learning how to perform vertical surveys with GPS and GULFNet or collaborating with a colleague who can. Some are working together to re-measure frequently used bench marks to serve them temporarily. Others are asking NGS State Advisor, Denis Riordan, and C4G to measure or set some for them.

The attitudes of bureaucracies concerning new technologies have also changed. Neither NGS nor C4G has the resources to re-level all the bench marks in the state. Conventional geodetic leveling costs $1,500 to $2,000 per mile to execute. That comes to upwards of $16 million to cover the primary network routes for the state’s control. GULFNet can be completed for a fraction of that cost with the added benefit of not going stale like conventional bench marks. C4G, with support from FEMA and NGS, are starting a project to increase the number of CORS in the network, run some conventional levels, and include gravimetric measurements to verify the new values. Included is a pilot project to provide a network-based RTK solution for southeast Louisiana. FEMA estimates that savings by avoiding increased Base Flood Elevation certificate costs alone would exceed $50 million! That will be welcome change indeed.

A new standard is developing among surveyors for executing control surveys. Points of interest are identified. Multiple (2 minimum) long GPS occupations (2-1/2 to 5 hours) are made on the points. Data from surrounding CORS are downloaded. The occupation data is submitted to NGS’ Online Positioning User Service (OPUS). Averages of the OPUS results are used as seed values from which the usual GPS network processing and adjustment takes place. Excellent results are the rule.

Another big change had its genesis prior to the storms with its significance brought into focus in their wakes. Despite efforts in opposition by LSPS, the legislation sponsored by large commercial land owners and the railroads became Act 802 of the 2003 legislative session. It amended RS14:63 relative to criminal trespass. The change was drastic. Where landowners were once required to actively claim their property and prohibit trespassing, the new statute forbids setting foot on any property that is not one’s own or known to be public. Surveyors had once presumed right of entry in the execution of duties; now they may only enter property for the purpose of a survey until asked not to. A hostile neighbor can effectively prohibit, or at least postpone, someone from verifying his property’s extent. One issue to be settled is whether the act stopped prescriptive rights from running, since one cannot enter another’s property without permission, and to do so is criminal. Can one meet the requirement to notoriously occupy? After the storms’ immediate emergencies abated, there remained many legitimate reasons for public officials or their contractors to enter people’s property. Act 802 became a stumbling block. Public officials, no longer responding to eminent danger, need permission to enter. Locating absentee property owners is a difficult chore.

The change in trespass law is joined by another tradition in Louisiana in ways that may serve to hamper recovery in storm ravaged areas. Louisiana’s French heritage includes patience with government (courtly) excesses, but one’s property was sacrosanct. The politicians could meet and plan and do what politicians do, just "don’t take my land." The homestead exemption is almost absolute in Louisiana. It has traditionally been set high enough that only the wealthiest might owe taxes on their homes and land. Until recent decades of inflation, this worked. Even now the amount of property taxes is much lower than in most other states. The U.S. Supreme Court ruling of June 23, 2005 that upholds the legitimacy of applying eminent domain on the basis of increased revenue may be particularly damning to landowners in a state that has a high homestead exemption (ostensibly to preserve one’s right to the property). A simple lemonade stand may generate more revenue than the homeowner pays in taxes. Silly changes in law alter the playing field in surprising and unexpected ways shown in the light of the storms’ wakes.

Some changes began forty years ago following Hurricane Betsy. A Corps of Engineers’ website notes that "Betsy prompted Congress to authorize a ring of levees 16 feet high around the city…" Betsy wiped out the fishing communities of St. Bernard Parish in 1965 similarly to the way Katrina did in 2005. After Betsy, the "powers that be" didn’t deem it significantly important to aid those who were rebuilding in determining that the property was indeed their own. One result was many built and occupied wrongly assumed lots ever since. (Prescription without color of title in Louisiana is 30 years.) Those people had good evidence of continuous occupation for 40 years that would enable a good claim to be made. Katrina changed that by wiping out that very evidence of occupation. Going forward, the GULFNet system should enable all surveyors to locate any survey relative to all others with a certainty only barely dreamed of in the past.

Hurricanes and a subsiding coast are simply "nature doing what nature does." Springtime brings an abundance of bright green in the swamps and forests are blown clean of leaves by the high winds and water. Nature doesn’t know disaster. Nature goes on. Disaster is a description of what happens when man’s expectations are too ambitious or too naive or when he thinks he understands, or even worse, controls nature. Disasters only happen to the artifacts of man. That doesn’t change.

One change is very positive. Surveyors are consulted more quickly since the storms. Warnings by surveyors are taken more seriously now. Surveyors’ expertise is wanted. Surveyors, in turn, are talking to scientists, seeking better understanding of the processes at work. Some of these processes are geologic, some environmental, some sociological, some political. Louisiana surveyors have a strong collegial bond. With the obvious exception of Act 802, they have many legislators who seek their counsel.

Louisiana surveyors are in the midst of many changes. The trusty, ol’ bench marks have abandoned them. They are seeing business as feast or famine. Many have to stretch to serve their clients well. Legal requirements are changing. Definitions are shifting. Their opinions are requested. It is the best of times. It is the worst of times.

One needs to live in Louisiana to understand her and her children. Like the jazz funeral, weekly festivals and Mardi Gras in a dilapidated city, the need to celebrate LIFE is innate and imperative. The unspoken but well understood principle that life is change is a deeply ingrained instinct. That said, it seems, too, that the more things change, the more they stay the same. Life is change; those who understand that this truth doesn’t change are able to carry on. Surveyors are no exception.

Tony Cavell is Associate Director of the LSU Center for GeoInformatics & Louisiana Spatial Reference Center in Baton Rouge.

Sidebar
A Few French Terms

bals de maison [house dances] Parties or soires usually requiring a large residence. These were ritzy affairs.

c’est la vie [it’s the life] A phrase idiomatically translated as "That’s life." The author’s meaning is more literally "It’s life."

carnival [from carne, meat + levare, to remove] Prior to the period of fasting during Lent, this became the period of merrymaking and feasting. Due to lack of adequate refrigeration, families, butchers, indeed entire towns would feast on meat that would otherwise go to waste.

cochon de lait [milk pig] A community affair in which the butchering and/or cooking of a suckling pig, roasted over coals for hours and served to all assembled.

fais do-do [go to sleep] Pronounced fay doe doe, this is a type of community social held in the evening to which even the children were brought and who would eventually tire and fall asleep. It was a social place acceptable for young Cajun men and women to meet, dance and socialize. Today it usually means a nighttime dance-social.

Mardi Gras [Fat Tuesday] This carnival celebration, French in origin, is most famous in New Orleans. It is a proper noun, so substituting the English is incorrect. In 1699, Pierre Le Moyne, Sieur d’Iberville, sailed to the mouth of the Mississippi on Shrove Tuesday and celebrated Mardi Gras with a mass. This place is still known as Mardi Gras Island.

A 1.818Mb PDF of this article as it appeared in the magazine complete with images is available by clicking HERE

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