FLOOD03422

• County: Statewide
• Community: na
• Basin: Statewide
• Title: Flood Hazard Mitigation Plan
• Date: 2/1/1998
• Prepared For: State of Colorado
• Prepared By: CWCB
• Floodplain - Doc Type: Flood Mitigation/Flood Warning/Watershed Restoration

199a - Colorado Rood 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_______________ _______. _______.__________u ___________.__ ___________.________ ._____:__.._.__________. 1-1
1.3.2 State u _ _. _ _ _ _._ _ _ _ _ __ _ _ _ __ _ _ __ _ _ _ _ ___ _ _ __ _. _ _ _ _ _ __ _ _ __. _ _ _ _ ___ _ _ _ _ _ _ __ _ _ _ _ __ _ _ _ _ _ __ __ _ - - _.._ - -. __ __ _ _ _ __ __ _ _ _ 1-1
1.3_3 Local Govemment._..._______..________._.._____..._______.._______..________._________....___________ 1-2

1.4 Goals and Objectives ............................................................................................... 1-2
1.5 DetinitiollS................................................................................................................. 1-2
2.0 Hazard Identification and Evaluation . 2-1

2.1 People and Hazards......................:........................................................................... 2-1
2.2 Types of lfazarrls...................................................................................................... 2-1
2.2_1 Floods __ __ _ __ _ __ _ ___ __ _ _ _ __ __ _ _ _____ _'_ _ _ __ __ _ ___ ___ _ __ _ _ __ __ __ __ _ _ __ _ -. - u ___ _ _ _ _ _ _ _____ -. -- -. _ __ __. _ _ __ _ _ _ _ 2-1
2_2_1_1 General Rain R<>ods.._____..___._______________.______________u___._.____.u_______ 2-3
2.2_1.2 Thunderstorm Roods _______._.._______._______.__________________.__.______________ 2-3
221_2_1 19lJ7 - Rood Event Description _____________.u____________ 2-4
2.2_1_2_2 191)7 - Surface and Hydrology_____._______.______..___u___ 2-6
221_3 Snowmelt Roods_.__________________.__________.._____________._____u________________ 2-6
2_2_1.4 Rain on Snow Roods___._________._____.___._____.u_____.__________________________ 2-7
2.2_1_5 Ice Jam Roods_u______u___._______u____________u___.______________u_____u________ 2-8
2_2_1_6 Dam Failure Roods ___._________________._________________________.__________________ 2-8
2_2.2 Geologic Hazards Closely Associated with Flooding _______u._______.________________ 2-9
2_2.2_1 Mud and Debris Rows_____._________________________________._______________.______ 2-9
2_2_2_2 Catastrophic Landslides___________u__________.______._____________________________ 2-9

2.3 Historic Damages .........................................................................,..~.......-............. 2-10
2_3_1 Flood Damages___________________u__________.________________________;_____._.______________._ ------ 2-10
2_3_2 Mud and Debris Flow Dam:ages__u______u._____________._______________.uu___u_____u____ 2-11
2_3_3 Catastrophic Landslide DaiTIages u____u___________._____________________u_____uu____u__ 2-11
2_3_3_1 Buffalo Creek Flood Event (1996)______________________.______...______.____ 2-11

2.4 Risk Information ..................................................................................................... 2-12
2.4.1 Loss Polenlialu_______.__u_.__.u_______...______________._______._______________________________._u 2-13
2.4.2 Polenliallmpact of No Action ______._______._______._____._______.______.uuu__.______u_____ 2-13
3.0 Capability Assessment 3-1

3.1 Legal Framework...................................................................................................... 3-1
3_1_1 Floodplain Management.____.__u____._______________u_______._.___._.____________._________._____ 3-1
3_1.2 Geologic Hazard Management _____________________.________________________.___._______________ 3-1
3.2 Govemment Organizations & Roles of Different Levels
and Internal 6rgan;zations.......................................................................................3-1
3_2_1 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 CQIorado Water Conservation Board______________._____ 3-2
3_2_1_2_2 CQIorado Geological Survey_______.u_______________________ 3-4
3_2_1_2_3 Division of Water Resources ____.______._______________.____ 3-4
3_2_1_2.4 Colorado Soil Conservation Board_____._____________.____ 3-6
3_2_1_2.5 Division of Wild/ife _________.______________________________________ 3-6

Contento. 3

1129/98 8:44:35 AM .