FLOOD02980

• County: Summit
• Community: Breckenridge
• Stream Name: Blue River
• Basin: Colorado Mainstem
• Title: Floodplain Information Blue River
• Date: 11/1/1974
• Prepared For: Breckenridge
• Prepared By: Leonard Rice Consulting Water Engineers, Inc.
• Floodplain - Doc Type: Floodplain Report/Masterplan

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Over half of the area in the Blue River basin above Brecken-

ridge is
tundra.

spruce,

above timberline with vegetation limited to alpine
The remaining is land is predominantly covered by
fir, pine, aspen, willows, sage and grassland.

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Above the town, all the tributary basins draining into the
Blue River from the Tenmile Range on the west have been glac-
iated, whereas the tributaries draining into the Blue River
from the east have not. As a result of the different geo-
logic origins, the tributaries on either side of the Blue
River have different hydrologic properties, Sub-basins that
have been glaciated have soils developed on glacial material,
These soils are generally coarse textured and may vary from
a very stony or rocky clay to a very coarse textured gravel
with boulders and cobble. Infiltration rates and losses for
this type of parent material can be high. In the non-glaciated
basins east of the Blue River, the soils have been developed
on very hard dense igneous and metamorphic rocks. Infiltra-
tion rates and losses through soils or debris developed on
the igneous rocks may be relatively low. The valley of the
Blue River also has been glaciated and land located within a
half mile to one mile on either side of the river is covered
by glacial material. Consequently, infiltration rates and
losses are exceptionally high,

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Below the town, the drainage basins on either side of the
Blue River differ markedly from those above the town. Geologic
conditions are different in that the parent materials for soils
are sedimentary rocks or alluvial fans. Hydrologic properties
of soils developed on these materials can be different than
those developed on parent materials located above the town of
Breckenridge. Infiltration rates and losses through the soils
developed on sedimentary rocks may be relatively low whereas
infiltration rates and losses through soils developed in the
alluvial fans may be moderate to high. However, local varia-
tions of infiltration rates and losses may vary considerably
within each major area.
~ Leonard Rice Consulting Water Engineers, Inc.