FLOOD03173

• County: Statewide
• Community: All
• Basin: Statewide
• Title: State of Colorado 2002 Flood Documentation Report
• Date: 1/1/2003
• Prepared For: CWCB
• Prepared By: ICON Engineering, Inc.
• Floodplain - Doc Type: Flood Documentation Report

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According to an article published by the Rocky Mountain News, during the July 2l st
storm, 2.0 inches of rain fell in approximately l.5 hours. This value is unusually high and
does not concur with the other precipitation amounts that were documented, or the
obtained radar images. The data source for this information was not documented, nor was
it determined where this precipitation was recorded. It is possible that this amount of
rainfall did occur in a localized area however, for the benefits of this analysis, this value
is thought to be an outlying data point and is therefore not considered in the storm
frequency analysis.

No flow gages were analyzed or considered in this analysis because there were no reports
of flooding due to nearby streams.

Flooded Area Description

Since no rivers or streams flooded during the two studied events, few areas sustained
major damage or were underwater.

During the July 10th event, the Lost Valley Dude Ranch sustained minor flood damage
from a "river of frothy black water" that covered the area (Emery, l). The ranch is
located within a natural drainage-way where runoff from the storm began to concentrate
before flowing down its drainage path. The dude ranch is located just off Jefferson
County road 126, which is also known locally as South Deckers Road.

South Deckers Road had to be closed during the July 21 51 event due to a four foot deep
river of water flowing across the road near "...Six Mile Hill, which is south of Forest
Road 550 and north of Deckers" (Denver Post, I).

Estimated Flood Dama!!:es & Anv Special Factors Affectin!!: the Flood

Since the studied events were minor in origin (both less than 2-year events) with no rivers
or streams flooding, damage to infrastructure and personal property was minimal.

The only reported damage from the July 10th event was to the Lost Valley Dude Ranch. A
small amount of water found it's way into the lodge soaking a $10,000 area rug (Emery,
1). It is assumed the ranch also sustained some clean-up costs associated with the "river
offrothy black water" but these costs were unknown at the time of this report.

No damage or associated cost estimates were reported for the storm on July 21 st. Most
likely, there was erosion damage and clean-up costs for South Deckers Road but, these
costs were unknown.

No injuries or casualties were reported from these events.

The Hayman Fire was a unique factor that affected the storm events analyzed in this
report. In fact, it is reasonable to conclude the damage from this fire caused, or at least
increased, the effects from the storms. The hydraulic conclusions suggest these storms
ICON 5ng'neec ng, Ine 6 January 2003