FLOOD02855

• County: Larimer
• Community: Larimer County
• Stream Name: Big Thompson River
• Basin: South Platte
• Title: Big Thompson River Flood Report
• Date: 10/1/1976
• Prepared For: Larimer County
• Prepared By: UDFCD
• Floodplain - Doc Type: Flood Documentation Report

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CONTENTS

TABLES

Page

Page

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Conversion table
Abstract
Introduction

.. __"____n_n_n 2

Table 1.
Table 2.

Peak discharges, Larimer County. Co]o., July 31-August I, 1976 10

High-water elevations and cross-section data at selected
sites on the Big Thompson River basin un _ m____ 11

High-water elevations and cross-section data at selected
sites on the ),Jorth Fork Big Thompson Hiver .... m________ _______...... 11

Uuuuuuuuuuuuu 3
3
3
3
5
10

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Table 3.

AcknowledgmeIlts
General meteorological
The flood
Flood stages, discharges, and flooded areas

conditions

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CONVERSION TABLE

English nnits in this report may be expressed as metric units by use
following conversion factors:

To convert English units
inches (in)
square miles (mil)
miles (mi)
feet (ft)
cubic feet per second (ft'ls)

of the

ILLUSTRATIONS

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Figure 1. ~lap showing location of flood areu, flood-data sites,
and total prceipitatioll _______n_u___"m_m___

Multiply by
25.4
2.590
1.609
.305
0283

To obtain metric units
millimeters (mm)
square kilometers (km')
kilometers (km)
meters (m)
cubic meters per second (m ~/s)

'uu'uuuuuu 4

2-10. Photographs showing:

2. Aerial views of "before" and "after" the flood at
Waltonia, Co]o. .uuuu.uu............ ...........u uuu. uu..... 6

3. Aerial views of "'before" anu "after" the flood at
Cedar Cove, Colo. . un.. .....u... 6

4. Destrllction of U.S. Highway 34 in
Big Thompson Canyon 7

5. Destruction of homes and vehicles at Drake, Colo. .......mm. 7

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Uebris from the Big Thompson Canyon piled up
against a railroad bridge at Loveland, Colo.. __..__ ___________m.

Silt deposited on inside of bcnd, North Fork Big
Thompson River near Drake, Colo. ____ _________.................... 8

8. Remains of Lovclanu powerplant near Cedar Cove, Colo. 9

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6.

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7.

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Big Thompson River near mouth of canyon, near
Loveland, Colo. unuu.............

u............ 9

10. Big Thompson River at mouth of canyon, near
Loveland, Colo. Note irrigation siphon washed
out and end of U.S. Highway ,34 uuuuuuu........ 9

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Figure 11. lnuex of aerial photographs showing flood outlines _

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Plates 1-51. Aerial photographs showing outline of flood area
along the Big Thompson River.

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NFI-NF15. Aerial photographs showing outline of flood area
along the \Iorth Fork Big Thompson River ..

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