FLOOD09522

• County: Logan
• Community: Sterling, Atwood
• Basin: South Platte
• Title: Pawnee Creek Flood Mitigation, City of Sterling, Town of Atwood and Logan County
• Date: 7/1/1999
• Prepared For: Logan County
• Prepared By: URS Greiner Woodward Clyde
• Floodplain - Doc Type: Flood Mitigation/Flood Warning/Watershed Restoration

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TABLE OF CONTENTS

Section 1.

Section 2.

Section 3.

Introduction ........ .......................... ....... ..... ....................... .............. ........... ...................... 1.1

1.1 Background.............................................................................................. 1.1

1.2 History ...................................................................................................... 1.1
1.3 Purpose and Need .................................................................................... 1-2

Alternatives Cons idered ............... ........................ ..... ..... ............... .......... ................ ...... 2.1

2.1 Alternatives Analyzed and Dismissed ..................................................... 2-1

2.1.1 Flood Control Levees................................................................... 2. I
2.1.2 Upstream Flood Control Reservoirs ............................................ 2-1
2.1.3 Construction of Drainage Floodway Upstream of Atwood ......... 2.2

2.2 Alternatives Carried Forward................................................................... 2.2

2.2.1 Alternative I - No Action ............................................................ 2-2
2.2.2 Alternative 2 - Improve Routing of Pawnee Creek Flood
Flows (Proposed Action) ............................................................. 2.2

Affected Environments and Environmental Consequences ...................................... 3.1

3.1 Geology and Soils.................................................................................... 3.1

3.1.1 Alternative 1 - No Action ............................................................ 3-1
3.1.2 Alternative 2 - Improve Routing of Pawnee Creek Flood
Flows (Proposed Action) ............................................................. 3-1
3.1.3 Alternative 3 - Pawnee Creek Overflow Cutoff........................... 3-2

3.2 Land Use and Planning ............................................................................3.2

3.2.1 Floodplain Encroachment ............................................................ 3-3

3.2.1. I Alternative 1 - No Action ............................................. 3-3
3.2.1.2 Alternative 2 - Improve Routing of Pawnee Creek
Flood Flows (proposed Action) .................................... 3-3
3.2.1.3 Alternative 3 - Pawnee Creek Overflow Cutoff............ 3-4

3.2.2 Prime Fannland....................................... .............. ....................... 3-4

3.2.2.1 Alternative 1 - No Action ............................................. 3-5
3.2.2.2 Alternative 2 - Improve Routing of Pawnee Creek
Flood Flows (Proposed Action) ....................................3-5
3.2.2.3 Alternative 3- Pawnee Creek Overflow Cutoff............ 3-5

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