FLOOD11555

• County: Larimer
• Community: Larimer County and Incorporated Areas
• Basin: South Platte
• Title: FIS - Larimer County and Incorporated Areas - Vol 4
• Date: 6/17/2008
• Prepared For: Larimer County
• Prepared By: FEMA
• Floodplain - Doc Type: Current FEMA Regulatory Floodplain Information

TABLE OF CONTENTS

Volume 1

Page

1.0 INTRODUCTION.............................................................................................................. 1

1.1 Purpose of Study..... .................................. .................. ....... ................. ........... ..... ........... 1

1.2 Authority and Acknowledgments .................................................................................. 1

1.3 Coordination............................................................................................................ ...... 5

2.0 AREA STUDIED .............................,................................................................................. 8

2.1 Scope of Study....... ......................,.............. ....................... ........................ .................... 8

2.2 Community Description.................................................................... ............................. 9
2.3 Principal Flood Problems......................................................................................... .... 14
2.4 Flood Protection Measures........................................................................................... 17

3.0 ENGINEERING METHODS..................... ...................................................................... 19

3.1 Hydrologic Analyses....................... ........ ........................................................... .......... 19

3.2 Hydraulic Analyses...................................................................................................... 21

3 .3 Vertical Datum............................................................................................................. 34

4.0 FLOOD PLAIN MANAGEMENT APPLICATIONS..................................................... 40

4.1 Flood Boundaries....................,.................................................................................... 40

4.2 Floodways .................................................................................................................... 42

5.0 INSURANCE APPLICATIONS .................... ................................................................ 135
6.0 FLOOD INSURANCE RATE MAP .............................................................................. 136

7.0 OlliER STUDIES ......................................................................................................... 138

8.0 LOCA nON OF DATA ................................. ................................................................ 142

9.0 BIBLIOGRAPHY AND REFERENCES....................................................................... 142
10.0 REVISION DESCRIPTIONS.................................................................. ...148