Animals in Research Facilities / 87- The rainfall overwhelmed the city’s fl ood-control systems. The
most severe damage occurred in two areas: downtown Houston and
the Texas Medical Center (TMC), often described as the “city within
a city.” The TMC is the world’s largest medical complex. Its nearly
seven-hundred-acre campus encompasses thirteen hospitals, two
medical schools, four schools of nursing, and numerous research
facilities, including Baylor College of Medicine and the University of
Texas Health Sciences Center at Houston. Consequently, the TMC
houses countless animals used in research.
The TMC sits in a bowl-shaped depression. Through it runs
Brays Bayou (sometimes spelled “Braes”), part of the network of
bayous, gulleys, and culverts that makes up Houston’s drainage
system. The region regularly receives intense rainfall; in Harris
County, where Houston is located, fl oods occur fi ve to eight times a
year and reports of destructive fl ooding date to 1843, shortly after
the city’s founding. To complicate fl ood management efforts, Hous-
ton has experienced tremendous population growth, nearly dou-
bling its population during the 1950s and again in the 1960s. As
the population has grown and the urban areas have expanded, the
amount of cement and blacktop infrastructure has only increased
the risk of fl ooding. When Brays Bayou was built in 1968, it could
contain water from a one-hundred-year fl ood event. However, rapid
development has “degenerated” its capacity. Engineering stud-
ies indicated that, by 1999, Brays Bayou could barely handle the
water from a ten-year fl ood.^6 As Allison stalled over Houston in
June 2001, the city received 80 percent of its total annual rainfall
in fi ve days. Most of the bayous overtopped their banks, and sev-
eral exceeded one-hundred-year fl ood levels. In downtown Hous-
ton, surface water run-off alone reached depths of fi ve feet.
When the storm moved north and the rain abated on Friday,
June 8, TMC employees headed home for the weekend. Thus, few
were on campus when the fl ooding began. According to reports,
many tried to reach the complex but found the area roads inun-
dated and impassable. Houston has the world’s largest pedestrian
tunnel system. At the TMC, the tunnels provided a conduit that car-
ried fi lthy water directly into the buildings. Water poured down