Cleaning up after Hurricane Ike
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About 50 miles southeast of downtown Houston in eastern Texas is one of the oldest and largest healthcare complexes in the state—the University of Texas Medical Branch (UTMB) at Galveston. Spanning 85 acres with seven hospitals and an assortment of specialized clinics, centers, and institutes including a medical school, the UTMB is not only the primary health science center for Galveston, but also the largest employer on Galveston Island and the seventh largest in the eastern Texas region.
On September 13, 2008, Hurricane Ike wreaked havoc on the UTMB campus, bringing with it a wall of water over 13 ft high and 100-plus mph winds. The storm’s surge from the Gulf of Mexico inundated approximately 750,000 sq ft of the campus’ facilities. Several campus buildings took on corrosive saltwater in basements, ground floors, and first floors. The MEP equipment in more than 60 of the 121 buildings on campus was severely affected, resulting in more than $700 million worth of damage.
Days before Hurricane Ike made its landfall, UTMB’s catastrophe action team mobilized a large group of people to minimize the damage that would occur. An explosion at a nearby yacht basin, just hours before the storm’s arrival, forced the UTMB staff to shut off the outside fresh air units to protect people inside the hospital complex from the smoke.
After Hurricane Ike pounded the campus, the catastrophe action team tore down damaged walls, removed debris, and pumped more than 1,000,000 ft3 of water from several buildings. Numerous portable chillers, generators, air handlers, and dehumidifiers were brought in to restore electrical service to as many buildings as possible.
Within a few hours, the storm flooded UTMB’s vast network of underground steam pipes and seeped through its insulation jackets, jeopardizing its ability to provide steam to several buildings. To restore steam service, UTMB staff dried out the insulation jackets for three days by pushing steam through the pipes, much like drying out a wet towel using a hot iron.
Biological contaminants also complicated the cleanup efforts. These included Legionnaire’s bacteria, borne by the flood waters, which forced the UTMB staff to flush potable water lines using a chemical disinfectant.
After the initial cleanup efforts, UTMB turned to Lockwood, Andrews & Newnam Inc . (LAN) to conduct a detailed assessment of all the MEP equipment exposed to seawater in each building and provide a report summarizing recommendations and options for dealing with the damage.
With a team of engineers and a basic floor plan of each building, LAN began the task of assessing the MEP equipment in the basement, ground floor, first floor, and the roofs of more than 80 buildings in three weeks. UTMB staff provided a priority list of buildings, which enabled the team to approach the task methodically.
During the assessment, engineers found that almost all the buildings had suffered some form of flood damage, with water levels ranging from several inches deep to almost 6 to 8 ft in certain buildings. In extreme cases, such as the Rebecca Sealy Hospital, which houses UTMB’s day surgery services, entire wall sections were destroyed and mechanical rooms were swamped. The food service area in the first floor of John Sealy Hospital, a 414-bed general care teaching hospital, also was heavily damaged.
Furthermore, the equipment in some of the buildings had been in use for a long time, with some of the switchgears and motors running continuously for almost 15 to 20 years. The combination of seawater and old age caused several electric motors, transformers, fire alarm systems, switchgears, electric panels, and associated power conditioning equipment—as well as pumps, air handlers, and other rotating machines—to shut down.
“Subjecting equipment that is complex, largely metal, and that relies on electrical power to saltwater is typically problematic at best,” said Jeffrey Thomas, LAN’s project manager. “Adding the dirt and debris found in a flood condition to the bath mixture makes the potential for long-term damage even greater.”
Consequently, engineers were concerned that even if the equipment was cleaned and restarted quickly, further issues such as failure of contacts due to corrosion, entrapment of water in windings and coils, and contamination due to mold growth would surface over time, ultimately resulting in the equipment’s failure.
After investigating the various types of equipment and considering their responses to saltwater exposure and its subsequent effects over time, the assessment team recommended the following short- and long-term solutions:
Replace all electric motors subjected to water. The majority of the motors are small totally enclosed, fan cooled (TEFC) motors, which makes replacement more economical than disassembly and cleaning. Even operational motors with no apparent damage are likely to fail due to the effects of corrosion.
Clean visible connections at the lugs of submerged transformers and reapply the bonding agent. Inspect the internal components of flooded transformers to determine if the transformer needs to be replaced.
Disassemble, clean, inspect, and replace the bearings and seals of blowers, pumps, and compressors subjected to immersion.
Clean and disinfect coils, pans, air handlers, and ductwork. Replace or re-insulate air handlers and internally insulated ducts subjected to immersion.
Replace feeder conductors submerged in more than 12 in. of water.
Replace fuses and molded case circuit breakers exposed to water. Test larger breakers and disconnects under load with the help of a reputable testing agency to ensure proper operation.
Control panels, fire alarm systems, and variable frequency drives (VFDs) contain many parts that are both mechanical and electronic. The cost of inspection, tear-down, assessment, and repair would greatly exceed the cost of unit replacement in most cases. Replace these parts at the manufacturer’s or distributor’s discretion.
Clean and replace boilers at the manufacturer’s discretion.
Replace chiller control panels and other electronic parts at the manufacturer’s discretion.
Re-insulate exposed pipes and tanks and replace domestic water heaters with more energy-efficient models.
Replace any equipment with wet insulation. The potential for mold, fungus, and other contaminants and the difficulty of cleaning these items makes remediation cost-prohibitive.
The scale and complexity of the assessment presented numerous challenges. Some of these were environmental. The adverse conditions due to the storm forced the team to crawl around dark, hot, muddy buildings that harbored mold, mildew, and debris in order to conduct the assessment.
The flooding in the basements and ground floors of many buildings also raised concerns about access to the buildings. In some buildings, engineers couldn’t do the initial assessment because the basements were inundated.
Many of the buildings at the UTMB campus are 30 to 40 years old. As a result, during the assessment, the record drawings sometimes didn’t reflect the exact location of the mechanical and electrical rooms, which made finding the equipment an exacting challenge.
The team also had difficulty ascertaining the electrical source of certain equipment. UTMB’s electrical infrastructure is built in such a way that a switchgear in one building also feeds several other buildings. Consequently, while assessing a switchgear panel, engineers weren’t sure whether the panel was getting fed from the building they were assessing or from a different building.
UTMB is currently using LAN’s assessment report and recommendations as a starting point in its negotiations with the Federal Emergency Management Agency (FEMA) and other insurance companies to rebuild the campus. As of October 2008, the storm’s cost to UTMB was estimated at $710 million, with approximately $90 million for equipment replacement. According to Thomas, UTMB hopes to recover close to $100 million in potential insurance coverage.
Additionally, UTMB is considering designing preventive measures into buildings to minimize potential risk from future catastrophic events. According to Thomas, some of these measures might include:
Relocate the equipment from the basement and ground floor of the buildings to the first or second floor.
Expand the centralized energy plant. UTMB has a split system. The bulk of the campus is served by the centralized energy plant, while the older buildings, such as the Rebecca Sealy Hospital, are served by individual equipment. Because the central energy plant is built on a berm, the probability of the plant flooding due to a storm is minimal. Consequently, expanding the centralized energy plant’s service to the stand-alone buildings is a potential solution.
Eliminate switchgear panels that serve multiple buildings and give each building its own switchgear. This ensures that if a switchgear fails, it will affect only the building that it serves instead of multiple buildings.
Conduct a capacity planning study to estimate the total capacity of the power coming into the UTMB campus and determine whether it is being distributed properly.
Develop a list of critical buildings and design power solutions to these buildings.
While it will take time for UTMB to recover its losses and rebuild the campus, most buildings have resumed normal operations and UTMB is well on its way to a full recovery, thanks to the efforts of its staff and its team of contractors and consultants.
|Srinivasan is a technical writer with Lockwood, Andrews & Newnam Inc. (LAN), a planning, engineering, and program management firm.|