The Los Angeles River watershed, 1990 ENLARGE
PAST, PRESENT, AND POSSIBILITIES
1990s
The above map illustrates the flooding for a 100-year
storm event in Los Angeles River basin as predicted by the Army Corps
of Engineers' 1992 evaluation of the region's storm drainage system. The
table below compares this estimate with actual floods in the following
years.
|
1992 (est) |
1992 |
1993 |
1995 |
|
| Deaths |
500,000 |
8 |
9 |
4 |
| Damage in adjusted millions |
$2,300 |
$150 |
$150 |
$200 |
| Flooded Area % of non-mountainous area |
82 sq mi |
N/A |
N/A |
N/A |
| Peak River Outflow in cubic feet / second |
N/A |
N/A |
N/A |
N/A |
Data on the 1992 estimate for the damage of a 100-year flood is from Blake Gumprecht, The Los Angeles River (Baltimore: The Johns Hopkins University Press, 1999) p 278
Data on the 1992, 1993, and 1995 floods is from Mike Davis, Ecology of Fear (New York: Metropolitan Books / Henry Holt Company, 1998) p 8
Although the regions' flood control system prevented widespread inundation during the 1968-9 winter, in the following 25 years the population of the Los Angeles River basin increased by 25 percent. The roads, parking lots, and other solid ground surfaces of the urbanization associated with this population growth decreased the capacity of river basin to absorb flood water before entering the storm drains. Thus by the early 1990s the design capacity of the Los Angeles River channel had been exceeded by the increased waters of the 100-year flood. The renewed flood threat initiated the Corps' Los Angeles County Drainage Area project and counter proposals from the Friends of the Los Angeles River. Yet ultimately the Corps' plan was adopted, with projected completion date in 2001.
Searching the Federal Emergency Management Agency's website with the terms "Los Angeles Floods" yields a variety of articles, insurance information and maps related to flooding predicted by the Army Corps' 1992 evaluation of Los Angeles flood control system. Information about the Los Angeles County Drainage Area project is available from the Army Corps of Engineers - Los Angeles District.