FLOOD07020

• County: Statewide
• Basin: Statewide
• Title: Flood Hazard Mitigation Plan for Colorado
• Date: 2/1/1998
• Prepared For: CWCB
• Prepared By: Kistner and Associates
• Floodplain - Doc Type: Flood Mitigation/Flood Warning/Watershed Restoration

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1I9a. Colorado Flood Hazard Mitigation Plan (409)

Table of Contents I

Preface Contents-2
Table of Contents Contents-3
1.0 Introduction 1-1

1.1 Purpose..................................................................................................................... 1-1
1.2 Scope ........................................................................................................................ 1-1
1.3 Authority ................................................................................................................... 1.1
1.3.1 FederaL............. ....... ,..................... ............. ....... ............... ..... ................. 1-1
1.3.2 State..........................,.............................................................................. 1-1
1.3.3 Local Government............... ............... ....... ...... ............. ...........................,. 1-2
1.4 Goals and Objectives ...............................................................................................1-2
1.5 Definitions................................................................................................................. 1-2
2,0 Hazard Identification and Evaluation 2-1

2.1 People and Hazards......................:........................................................................... 2-1
2.2 Types of Hazards...................................................................................................... 2-1
2.2.1 Floods......................................... .........................,.................................... 2-1
2.2.1.1 General Rain Roods................................................................. 2-3
2.2.1.2 Thunderstorm Roods ...............................................................2-3
2.2.1.2.1 1997 - Rood Event Description ............................ 2-4 '
2.2.1.2.2 1997 - Surface and Hydrology.............................. 2-6
2.2.1.3 Snowmelt Roods...................................................................... 2-6
2.2.1.4 Rain on Snow Roods................................................................ 2-7
2.2.1.5 Ice Jam Roods......................................................................... 2-8
2.2.1.6 Dam Failure Roods ..................................................................2-8
2.2.2 Geologic Hazards Closely Associated with Flooding ..................................2-9
2.2.2,1 Mud and Debris Rows.............................................................. 2-9
2.2.2.2 Catastrophic Landslides............................................................ 2-9

2.3 Historic Damages ................................................................................................... 2.10
2.3.1 Flood Damages.....,............. .............. ...................................................... 2-10
2.3.2 Mud and Debris Flow Damages............................................................... 2-11
2.3.3 Catastrophic Landslide Damages ......................,..................................... 2-11
2.3.3.1 BuffaJo Creek Rood Event (1996)........................................... 2-11

2.4 Risk Infonnation ..................................................................................................... 2-12
2.4.1 Loss Potential.................................................................................,....... 2-13
2.4.2 Potential Impact 01 No Action ..................,...............................................2-13
3.0 Capability Assessment 3-1

3.1 Legal FrameWDrlr...................................................................................................... 3-1
3.1.1 Floodplain Management............................................................................ 3-1
3.1.2 Geologic Hazard Management .................................................................. 3-1
3.2 Government 9rganizations & Roles of Different Levels
and Internal Organizations.,..................................................................................... 3-1
3.21 State Departments .................................................................................... 3-1
3.2.1.1 Governor's Office ..................................................................... 3-2
3.2.1.2 Department of Natural Resources............................................. 3-2
3.2.1.2.1 Colorado Water Conservation Board.................... 3-2
3.2.1.2.2 Colorado Geo/ogical Survey................................. 3-4
3.2.1.2.3 Division of Water Resources ................................ 3-4
3.2.1.2.4 Colorado Soil Conservation &arrJ........................ 3-6
3.2.1.2.5 Division ofllVildlife................................................ 3-6

Contents. 3

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