FLOOD03190

• County: Morgan
• Community: Weldona
• Basin: South Platte
• Title: Flood Mitigation Project - Schaefer Draw/South Platte Basin
• Date: 8/1/1996
• Floodplain - Doc Type: Flood Mitigation/Flood Warning/Watershed Restoration

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Colorado Water Conservation Board
Department of Natural Resources
721 Centennial Building
1313 Sherman Street June 30, 1997
Denver, Colorado 80203
Phone: [phone]
fAX: [phone]

STATE OF COLORI\DO

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Roy Romer
Governol

Mr. Mark Arndt, Commissioner
Morgan County Government
231 Ensign
Fort Morgan, Colorado 80701

Jil.mes 5. Lochhead
Executive Director, ONR

DariesC. Lile, P.E
Director, (WeB

Dear Mark:

It was a pleasure to meet with you on June 18 regarding the insufficient storm drainage system in
Weldona. We have recently received your request for technical assistance in developing an
engineering feasibility study to address the drainage problems.

Larry Lang, Chief of the Flood Control and Floodplain Management Section, has informed me
that this study will be incorporated into our Section's new work plan. The new work plan will
become effective during July 1997. Upon completion, the draft feasibility study will be
presented to the County for review and comment. Our staff can readily provide the requested
technical assistance free of charge, however we are not a funding agency and do not have the
ability to provide grant money for project construction. The County would be responsible for
'-.../ making application to various agencies to obtain project funding.

In the meantime, I have performed some preliminary calculations for estimating the peak flow
and the culvert sizes for the State Highway 144 crossing. It is my understanding that the CDOT
will be paving the highway in the very near future, and the new culverts should be placed before
CDOT completes their work. Ideally, a 48" diameter culvert should be placed at the highway
crossing near Warren Street if the slope and cover requirements can be met. Otherwise, I would
recommend using two 36" or two 30" diameter culverts as the second and third options,
respectively. These sizes are based on a lO-year design flow of 90 cubic feet per second (ds) for
a 144 acre drainage basin to the north of the town. It was assumed that the area located to the
north of the Weldon Valley Ditch does not contribute to the storm runoff in Weldona.
Additional improvements will need to made within the town in order to reduce the flooding
problems. Those improvements will be addressed in the feasibility study.

If you have any questions regarding this issue, please contact me at [phone].

Tbem.al> W. Browning, P.E.
Flood Control and Floodplain Management Section

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