FLOOD09157

• County: Statewide
• Community: State of Colorado
• Basin: Statewide
• Title: Flood Hazard Mitigation Plan for Colorado
• Date: 1/1/1983
• Prepared For: State of Colorado
• Prepared By: CWCB
• Floodplain - Doc Type: Flood Mitigation/Flood Warning/Watershed Restoration

1.0

2.0

TABLg OF' CONTEN1~S

Page

Letter of Transmittal
Preface ...................."....
ACknowledgements
Table of Contents
List of Figures
Executive Summary

i
ii
v
vii
ix

INTRODUCTION

...............................................n....................... ..

1.1 Purposes . . 1
1,2 Scope .. . .. . 2
1.3 Authority ... 2
1.4 Definitions ., 3
1.5 Conceptual Emphasis ... .. ...... .. ................ .. ........ .. ........ .. 5

................................ n..............,..........................

7

BACKGROUND

2.1

...................... ..,...........0............

2.2

Lawn Lake Dam Failure

7

2.1.1 Setting ........ ... 7
2.1.2 The Flood ........ .. 9
2.1.3 People at Risk ., 11
2.1.4 The Warning ... .. . .. 13
2.1. 5 Loss of Life and Flood Damages ., 16
2.1.6 Agency ReSpOnSE! .... .. 18
2.1.7 Mitigation Measures 25

Identification of the Hazards

........................... ...

28

2.2.1 People and Floods .... .. 28
2,2.2 Historic Flood Damages 31
2,2.3 Causes of Floods .' . 35
2.2,4 General Rain Floods 37
2,2.5 Thunderstorm Floods " 37
2,2.6 Snowmelt Floods ...... .. .. . 37
2,2,7 Rain on Snow Floods 38
2,2.8 Dam Failure Floods 38

2.3

41

Legal Framework

.................... P.............................

2.3.1
2.3.2
2.3.3

41
42
45

Dam Safety ......................
Floodplain Management
Emergency Preparedness

2.4

Governmental Organizations

.. ... '................. ...........

46

2.4.1
2,4.2
2,4.3
2.4.4

City and
County Government
Regional Planning
State Government

..........".... ..

Town Government

46
46
46
47

..... '.

Agencies

v