FLOOD08183

• County: Summit
• Community: Breckenridge
• Stream Name: Blue River
• Basin: Colorado Mainstem
• Title: Floodplain Information Breckenridge
• Date: 9/1/1974
• Prepared For: Summit County
• Prepared By: Leonard Rice Consulting Water Engineers, Inc.
• Floodplain - Doc Type: Floodplain Report/Masterplan

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around Cemetery Road but the flow returns immediately to the
channel downstream of the crossing. Flooding on the Intermediate
Regional Flood is a function of crossing capacity which is
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~exceeded by the peak flows. As stated previously in the report,
'I all crossings were assumed to be operating and not plugged with
debris. However, it i~ possible, as in the case of the June 1965
'''-flood, that the crossings can become plugged with debris and
flooding can occur on a more widespread basis. The flooding,
however, would remain localized around the crossings.

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The Standard Project Flood also parallels the streambed of the
Blue River, but inundate much more land than the Intermediate
Regional Flood. All of the six crossings in the town are exceeded
in capacity and produce backwater effects which increase the area
inundated by flood waters. The flood waters roughly parallel
the Blue River and are restricted to within 200 to 300 ft. of
the channel bed in the Blue River above the Four Seasons area.
Immediately below the first pond in the Four Seasons area the
Standard Project Flood is no longer restricted to the narrow
band parallelling the river. At this location, the flood waters
back up into Illinois Gulch, cross Colorado State Highway No.9
and flow northward through the town. Flood water depths through
the town range from 2 to 4 feet. Because of the high elevations
of the western bank of the Blue River,'flooding does not occur
to the west, but remains very close to the active channel of the
river. Immediately below the Watson Street crossing, most of
the Standard Project Flood returns to the channel bed of the
Blue River and only a portion of the flood waters continue on
through the town. Flood water depths of the portion of the
flow that remains in the town downstream from the Watson Street
crossing are on the order of 1 to 2 feet. Most of the flow has
returned to the channel of the Blue River. Immediately upstream
from French Gulch, the entire flood waters from the Standard
Project Flood returns to the channel of the Blue River and the
flow remains within the channel until the next crossing. The