FLOOD00067

• County: Alamosa
• Community: Alamosa
• Stream Name: Rio Grande River
• Title: Flood Control Status Report for Alamosa County and City
• Date: 7/1/1987
• Prepared For: Alamosa County
• Prepared By: CWCB
• Floodplain - Doc Type: Project

I
I.
.

.'
I
I
I
I
I
1-,
I-
I
I
I
I
I
I
I
I
I

The reduction in magnitude was due in part to diversions by
irrigation ditches and natural storage in the floodplain.

3.1.2

1985 Flood Damages

The existing levee system at Alamosa was constructed by local
citizens to protect the City of A1amosa in the 1940s. The
levee system begins north of the City and continues to the
southwest of town near the sewage lagoons.

The Alamosa flood control levees contained the floodwater;
however, a number of locations were eroded and excessive
leakage occurred. The leakage occurred due to dense tree
population on and adjacent to the levees throughout the lower
reaches of the system. Failure of the levee was prevented by
constructihg a back-up dike and flooding the area between the
levees to back pressure the Alamosa levee system. The levee
system through the ci ty of Alamosa wi thstood the June flood
with two to three feet of freeboard with a number of locations
maintaining only {l. one foot freeboard. Had the levee failed,
the entire business section of Alamosa would have been
inundated. The Corps of Engineers and the Colorado Water
Conservation Board have stated that major flood events in the
future of 25-year or greater magnitude will outflank the upper
end of the levees and become tributary to the areas behind the
levees.

The Division of Water Resources Office in Alamosa, the Division
of Disaster Emergency Services out of Golden, and the Corps of
Engineers out of Pueblo provided technical assistance to Rio
Grande County, Alamosa County, and the City of Alamosa, during
the flood fight (Table 4).

Table 4. 1985 Flood Losses Estimated by Local Governments
(Reported as of July 31. 1985)
Alamosa City of
Damaqe Cateqorv County Alamosa Total
PUblic Facilities $ 92,120 $143,709 $ 235,829
Private Residential
and Commercial none
Property 142,000 reported 142,000
Private Agricultural none
Property 332,000 reported 332,000
Flood Fight
Activities 35,354 44,063 79,417
Total $601,474 $187,772 $ 789,246
-4-