FLOOD00275

• County: Adams
• Community: Westminster
• Title: Bruchez Farms Property - Big Dry Creek at Wadsworth Parkway
• Date: 1/1/1998
• Prepared For: Bruchez Farm
• Prepared By: Wright Water Engineers Inc
• Floodplain - Doc Type: Floodplain Report/Masterplan

I
II
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I

15

pond that, accordlno to the 1986 studY, would be 25 feet deep at the time the peak
discharge rate was approaching the culvert.

However, this Is not what would physically occur at the site. The depth of water

upstream from the culvert entrance will only rise to the height necessary to permit

the peak outflow rate to pass throuah the culvert as Illustrated In Figure 5, i. e. ,

the peak of the outflow hydrograph. The shaded area is the volume of storage up-

stream of the culvert being utilized. The greater the available volume of storage,

the greater w1l1 be the reduction In peak flow rate.

Total ExlsUng Volume
Using the available topographic mapping, the total volume of storage presently
existing upstream of the culvert was determined. The total available storage at
2-foot Intervals Is listed In Table 2. If the water surface elevation upstream of the
railroad culvert were 5364, about 300 acre feet of runoff would be temporarily
stored upstream of the culvert.

ExlsUng Volume Within the Floodway
At some point In the future, the land outside of the floodway upstream of the
railroad culvert could be f1I1ed. This would reduce the amount of storage available
for the temporary detention of flood water. For this reason, the volume of avail-
able storage upstream of the railroad culvert was recalculated, assuming that the
land outside the floodway had indeed been f1I1ed. These results are also listed In
Table 2.