FLOOD10386 ‎(2)‎

• Designation Number: 576
• County: Gilpin
• Community: Black Hawk
• Stream Name: North Clear Creek, Gregory Gulch and Chase Gulch
• Title: Floodplain Information Report - Black Hawk
• Date: 7/1/2004
• Prepared For: Black Hawk and CWCB
• Prepared By: Love and Associates
• Floodplain - Doc Type: Floodplain Report/Masterplan

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TABLE OF CONTENTS

PREFACE.. ..... ........... ..... ................. ......... ......... .... .... ..... ... ......... ........ ...... '" ...... ..... .... ... .... 1

TABLE OF CONTENTS .................................................................................................2

INTRODUCTION.............................................................................................................3

Purpose and Scope.... ...... .............. ................................... ........................................ ..... 3

Authorization................................................................................................................. 3

STUDY AREA DESCRIPTION. ...................................... ......................... ...................... 4
Community Description.. ..... ................ ........... ........ .......... ............................ ..... .......... 4

Watershed Description.................. ....... ..... ... ........ ...... ..... ....................... ..... .... ............. 4

Flooding Problems and Flooding History................................................................... 4

Previous Studies..... ..... ..... .... ..... ............................ ................. ......... ...... .................. ...... 6

Community Response to the CWCB Designation and Approval Process ...............8

ENGINEERING METHODS .......................................................................................... 9

Hydrologic Analysis ............. .......... ....... ........... ..... .,. ... ..... ........................... ........ ....... ... 9

Hydraulic Analysis...................................................................................................... 14

Floodplain Mapping.... ......... .......... ............................. ....... ........... ........ ...................... 19

FLOODPLAIN MANAGEMENT...... ................ .................... ............... .............. .......... 20
Local Ordinance Requirements........ .... .......... ....... ........... ............. .... ...... ............ ....... 20

Flood Insurance..... .................. ............... ...................... .......... .......... ...... .... ................. 20

Floodplain Management Alternatives........... ................ ........................ .................... 20

REFERENCES................................................................................................................ 22

Figures

Figure 1 - Vicinity Map
Figure 2 - FIRM Map (1984 and 1994 LOMR)
Figure 3A-3C - Catchment Areas and Design Points
Figure 4 -1979 Land Use
Figure 5A-5C - 100- Year Floodplain Delineation

Appendix

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