FLOOD04416

• Designation Number: 304
• County: Adams
• Community: Unincorporated Adams County
• Stream Name: Big Dry Creek, (ADCO), North area tributaries
• Basin: South Platte
• Title: Flood Hazard Area Delineation - Big Dry Creek, ADCO, North Area Tributaries
• Date: 7/1/1989
• Designation Date: 1/1/1990
• Floodplain - Doc Type: Floodplain Report/Masterplan

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The headwater area for South Fork Preble Creek lies in the vicinity of
160th Avenue and Huron Street. This drainageway flows in a northeast-
erly direction and joins Preble Creek where the latter crosses 168th
Avenue.

non-existent In the tributary hasins. and the sponsors are not aware of
any recurring problems. Flooding and drainage problems, therefore, are
the result of relatively rare and unusually intense storm events.

The Bull Canal and 1-25 cross South Fork of Preble Creek in the upper
part of the basin. Significant storage (i.e., approximately 60 AF)
through inadvertent detention exists at the 1-25 crossing.

The only problem reported by Adams County staff occurs at Colorado
Boulevard between 160th Avenue and 162nd Avenue where runoff overflows
the stream channel. This problem is reported to be caused by insuffi-
cient culvert capacity under the UPRR embankmenl.

Preble Creek
Preble Creek has a drainage area of approximately 7.2 square miles
which includes the South Fork Preble Creek basin. The stream flows in
a northeasterly arc from the headwater area to a point approximately
0.4 miles north of 168th Avenue along 1~25 before turning to the south-
east. The total length of the main channel is 5.2 miles, 3.6 miles of
which is within Adams County. At the east 168th Avenue crossing of
Preble Creek, the creek joins with South Fork Preble Creek.

Preble Creek IS a well-defined channel throughout most of its length.
Bank heights are typically 2 to 3 feet deep and relatively steep. The
channel geometry and environment are similar to that of Big Dry Creek.
In the reach between Big Dry Creek and the Weld County line (l68th Ave-
nue), the channel slope IS approximately one-half percenl. In the
western part of the study area, the channel slopes from I percent to
I. 3 percent.

Both the Bull Canal and 1-25 cross Preble Creek in Weld County.

C.

PAST PROBLEMS
The lack of development in
drainage-related problems under
vided by the sponsors indicate

the study area limits the extent of
present conditions. Information pro-
that flooding complaints are virtually

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