FLOOD04379

• Designation Number: 525
• County: Dolores
• Community: Unincorporated Dolores County
• Basin: San Juan/Dolores
• Title: Flood Insurance Rate Map - Dolores County, CO, Unincorporated Areas
• Date: 1/1/1978
• Designation Date: 9/1/2000
• Floodplain - Doc Type: Floodplain Report/Masterplan

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TABLE OF CONTENTS

PREFACE ....................................................................................................................................... ii

TABLE OF CONTENTS ............................................................................................................... iii

INTRODUCTION ........................................................................................................................... 1

PUI1'ose and Scope.. .... .... ................ ... ..... ..... .... .... ................ ... .... ... ... ..... ...... .... ..... ...... ...... ... 1

Authorizati on....................................................................................................................... 1

STUDY AREA DESCRIPTION .....................................................................................................2

Community Description ....... ...... ... ..... ........ ... ........ ........ ..... ... ... .... ... ....... ... .... ... .... .......... ..... 2

Watershed Description ... ....... ... ................ ... ........ ... ............. ...... ... ... ..... ... ... .... .... .... ....... ...... 2
Flooding Problems and Flooding History ...........................................................................2

Previous Studies .. ..... .... .... ... .... ... ........ .... ...... ...... ........ .......... ... .... ...... ........... .... .... .... ... ........ 3
Community Response to the CWCB Designation and Approval Process ..........................3

ENGINEERING METHODS ..........................................................................................................4

Hydrologic Analysis.. ..... ... .... ... ..... ... ... ..... ....... ...................... ... ....... ..... ............. .... ... ...... .....4

Hydraulic Analysis. ...................................... .... .... ............. ......... ........ ........... ..... ............. .... 6

Floodplain Mapping. .... .... ....... ............... ....... ....... ...... .......... ... ... .... ............. .... ... ..... ......... ... 6

FLOODPLAIN MANAGEMENT ..................................................................................................7

Local Ordinance Requirements ........ ... .... ... .... .... ... ... ... ............. .... .......... ...... ... ........ ............ 7

Flood Insurance ..... .... ..... .... .... ........ ... ... .... ... ..... ............ .......... ....... ............. ...... ..... .............. 7
Floodplain Management Altemati ves .... ...... ........ ...... ..... ..... ... ... ...... ........ .......... ..... ... ... ... ... 7

APPENDIX .....................................................................................................................................9
Designation Request Letter
Streams in Study
CWCB Hydrology Worksheets
USGS Hydrology Worksheet
Peak Discharge at Ungaged Sites worksheet
HEC-FFA Output

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