On June 30, 2002, a low-pressure system migrating westward
from Florida combined with a flow of deep tropical moisture
from the Gulf of Mexico and moved over southern Texas. The
system hit a wall of high pressure and stalled over the central
and south-central parts of the State. For 8 days, the storm
system continued to draw moisture from the Gulf, which triggered
several massive storms throughout much of the area. As much
as 35 in. of rain fell during the event, with heaviest depths
occurring in the Texas Hill Country northwest of San Antonio.
Flooding affected about 80 counties in Texas.
Heavy rain also fell in parts of West Texas, including Abilene,
where 12-14 in. of rain in the pre-dawn hours of July 6 caused
flooding that required numerous evacuations. Heavy rains also
caused Lake Brownwood to overflow, causing evacuations and
flooding in parts of Brownwood.
The floods caused 12 deaths and damage to about 48,000 homes.
Nearly 250 flood rescue calls were reported, more than 130
roads were closed, and thousands of homes and businesses lost
electrical power and telephone service. Twenty-four counties
were identified by the Federal Emergency Management Agency
(FEMA) as Federal Declared Disaster areas14 counties
were eligible for individual assistance and 10 counties for
individual and public assistance. Emergency management representatives
had not yet assessed the total cost of damages.
The storms produced large volumes of runoff and as many as
four flood peaks at each of many streamflow-gaging stations
in the Brazos, Colorado, and Guadalupe River Basins. Record
flood stages occurred at sites on the Medina River, San Antonio
River, Sabinal River, and Nueces River. For the first time
since it filled in 1968, Canyon Lake (northeast of San Antonio)
poured over its spillway, adding to the flooding in the Guadalupe
River. Emergency managers also were concerned about the 90-year-old
dam at Medina Lake (west of San Antonio). Medina Lake topped
its spillway and rose to within 18 in. of the top of the dam.
Areas downstream from the dam were evacuated as a precaution
because of the fear of dam failure.