Memorial Medical Center’s backup generators

Memorial Medical Center’s backup generators were the hospital’s lifeline after utility power failed during Hurricane Katrina—and a stark example of how a lifeline can depend on vulnerable connections. The three main generators stood above the rising water, but parts of the electrical system that distributed their power sat low enough to be flooded. After nearly two days of operation, the generators failed one by one. Two smaller generators later brought back limited electricity, useful for fans, lights, and cooling, but only after the principal backup system had gone dark.

A known vulnerability

After Hurricane Ivan narrowly missed New Orleans in September 2004, Memorial’s leaders reviewed their hurricane plans. Plant operations director Eric Yancovich attended a meeting with the U.S. Army Corps of Engineers and studied storm-surge models estimating that a major hurricane could drive twelve to fifteen feet of water around the hospital, which sat three feet below sea level. He then made a hand-drawn elevation sketch on lined paper, measuring hospital entrances and outdoor equipment against Magnolia Street, behind the hospital.

The sketch exposed the distinction between the generators and the system that made their electricity usable. The generators were on the second floor, at what Yancovich considered a safe elevation. But less than four feet of street flooding could send water over the loading dock and into the hospital, while crucial components of the emergency power distribution system—including transfer switches—were in the basement or only inches to a few feet above ground. Yancovich warned his supervisor that comparatively little water could disable most of the Medical Center. He anticipated that the main hospital could lose power and that patients would need to be moved to the newer Clara Wing, where he believed the electrical circuitry was better protected.

Some protective work was done: floodgates were added and the vent for the underground diesel tanks was raised. More extensive improvements were recommended for the low-lying transfer switches and for pumps supplying medical air and vacuum suction, both important to patients with respiratory problems. A partial bid for electrical work exceeded a quarter of a million dollars. Yancovich’s memo recorded that, because of a lack of capital, he did not expect the work to be approved at that time. Thus the later failure was not simply a matter of water reaching equipment no one had thought to protect: the hazard had been examined, sketched, and described in advance, while essential upgrades remained undone.

The three main generators under strain

The three teal-colored generators, each rated at 750 kilowatts, supplied electricity through a network of feed lines, riser circuits, and transfer switches. Each could produce roughly the power of six engines from a popular Toyota Camry. Under ordinary conditions, an outside company serviced them; Memorial’s maintenance staff mainly changed the oil and ran brief monthly tests. Those tests reflected national codes that treated hospital generators as support for vital functions lasting minutes or hours. Memorial’s disaster plan, by contrast, expected the equipment to carry the hospital for at least three days. By the time the failures described in the book unfolded, the generators had already been running for two.

No electrician or engineer on site was a generator mechanic. When one engine shut down and part of the hospital went dark, workers judged that it had overheated. Using flashlights, they added water to its radiator and managed to restart it. Later, they faced what appeared to be low oil pressure. They brought barrels of diesel in an effort to prime the motors and restart them, and crossed a bridge to the surgery building to get more fuel from a generator there. Meanwhile, some areas lost power; in others, the light seemed to dim.

The aging hospital’s electrical layout compounded the difficulty. Additions to the original 1926 building had left a system of separate but overlapping circuits, difficult for the workers to understand as a whole. When another generator failed, staff tried to connect some of the circuits it served to a working generator. Wearing rubber boots, they waded through knee-deep basement water and climbed to a mezzanine in the core electrical building. About a third of the automatic transfer switches were at a low level, where the water suggested that switches and associated distribution panels might already be submerged—a vulnerability Yancovich had predicted.

Failure and the last transfer

In a narrow corridor lined with electrical panels, beneath a warning sign about hazardous voltage, a worker used a flashlight to find a metal lever with a yellow rubber-coated handle. The bypass handle allowed the load from the failed generator to be connected to a working one. But a gauge soon showed that the operating engine was drawing too much current, suggesting a short circuit. The workers tried to separate the loads to reduce the danger of fire. That possibility was especially alarming because the sprinkler-system pumps were underwater and city fire trucks were presumed to be out of commission. They also shut off scattered branch circuits serving unused fixtures and devices in an effort to lower the demand.

Another generator failed. This time the workers had an idea of what had gone wrong, but no spare parts with which to fix it. They tried to salvage parts from the failed equipment; the repair did not work. The struggle to keep the generators operating lasted about two hours. At roughly two in the morning on Wednesday, August 31, nearly forty-eight hours after Katrina made landfall near New Orleans, the last backup generator surged and died. Ewing Cook, lying in his office on the second floor, heard the sudden silence. Alarms flashed and sounded elsewhere in the hospital; on the eighth floor, nurse manager Karen Wynn climbed onto a chair and struck an alarm panel with her shoe to quiet it.

Limited power returns

The main generators’ failure did not mean that no electricity would return. On Wednesday evening, after Yancovich came back from ferrying passengers in his fishing boat, he and his staff discovered and repaired two small generators. One electrician, who had feared being shot or having to shoot someone while assigned to security, instead worked on setting up a generator in the parking garage. The contrast was practical and consequential: equipment that might have helped patients dependent on electrical devices if used earlier was now brought into service after the main system had failed.

An extension cord ran from the garage through a stairwell into the lobby, powering a high-speed centrifugal blower normally used to dry floors. In the heat, it served to cool patients and staff. The renewed supply also brought back box fans and lamps collected around the hospital, supplementing cardboard fans and Coleman camping lanterns. The small generators lit a handful of old incandescent bulbs on the long-unused helipad; only a few of about thirty bulbs still had working filaments. This was not a restoration of the hospital’s original backup system, but a patchwork return of specific functions—air movement, some lighting, and relief from heat—after the larger generators and their vulnerable distribution network had failed.