Prepared For: Prepared By: In Cooperation with: GAINESVILLE COMMUNITY REDEVELOPMENT AGENCY SWEETWATER BRANCH DAYLIGHTING FEASIBILITY ANALYSIS Gainesville Community Redevelopment Agency | October 2015 1 TABLE OF CONTENTS 4 PERMITTING AND REGULATION .................................................................................................................... 52 4.1 Federal ............................................................................................................................................................ 54 0 EXECUTIVE SUMMARY ...................................................................................................................................... 6 4.1.1 United States Army Corps of Engineers (USACE) ................................................................................. 54 1 INTRODUCTION ................................................................................................................................................. 12 4.1.2 Federal Emergency Management Agency ............................................................................................. 54 1.1 Background ..................................................................................................................................................... 14 4.2 State ................................................................................................................................................................ 54 1.2 Objectives ........................................................................................................................................................ 14 4.2.1 Florida Department of Environmental Protection .................................................................................... 54 1.3 Power District Technical Advisory Team (TAT) .............................................................................................. 14 4.2.2 St. Johns River Water Management District ........................................................................................... 54 2 DATA REVIEW ................................................................................................................................................... 16 4.3 Local ................................................................................................................................................................ 55 2.1 History ............................................................................................................................................................. 18 4.3.1 City of Gainesville ................................................................................................................................... 55 2.2 Stream Flow .................................................................................................................................................... 18 5 RECOMMENDATIONS & IMPLEMENTATION STRATEGY ............................................................................ 56 2.2.1 Conclusions and Recommendations ...................................................................................................... 18 6 REFERENCES.................................................................................................................................................... 60 2.3 Geomorphic Data ............................................................................................................................................ 18 TABLES 2.3.1 Conclusions and Recommendations ...................................................................................................... 19 2.4 Infrastructure Analysis ..................................................................................................................................... 19 Table 1 Sweetwater Branch- Estimated Flood Stage and Peak Flow at SE 4th Avenue ................................... 18 2.4.1 Conclusions and Recommendations ...................................................................................................... 21 Table 2 Daylighting Study Area – Summary of Existing Infrastructure .............................................................. 20 Table 3 Sweetwater Branch Culvert Descriptions ............................................................................................. 21 2.5 Effective Special Flood Hazard Area .............................................................................................................. 21 Table 4 Sweetwater Branch- Estimated Flood Stage and Peak Flow at SE 4th Avenue ................................... 22 2.5.1 Estimated Flood Areas ............................................................................................................................ 21 Table 6 Relative Potential Benefits List ............................................................................................................. 38 2.5.2 Conclusions and Recommendations ...................................................................................................... 22 EXHIBITS 2.6 Historical Environmental Issues and Constraints Review ............................................................................... 22 nd th Exhibit 1 Streambank Erosion in Sweetwater Park (Between SE 2 Place and SE 4 Avenue) ....................... 19 2.6.1 Summary of Previous Assessment Activities .......................................................................................... 22 th Exhibit 2 Sweetwater Branch Creek Park at SE 4 Avenue ............................................................................... 19 2.6.1.1 Parcel 1 ................................................................................................................................................... 22 Exhibit 3 Examples of a Stream Channel and Floodplain with Retaining Walls .................................................. 39 Exhibit 4 Example of an Earthen Channel with Low Retaining Walls.................................................................. 41 2.6.1.2 Parcel 4 ................................................................................................................................................... 22 Exhibit 5 Sweetwater Branch Creek Daylighting Conceptual Rendering ............................................................ 41 2.6.5 Conclusions and Recommendations ...................................................................................................... 23 Exhibit 6 Wallers Creek in Austin, Texas during the Memorial Day 2015 Floods ............................................... 46 3 DAYLIGHTING.................................................................................................................................................... 36 Exhibit 7 Blue Road in Drachten .......................................................................................................................... 46 3.1 Qualitative Evaluation Methodology ................................................................................................................ 38 3.2 Current Condition ............................................................................................................................................ 38 3.3 Option 1 – Remove the Box Culvert and Replace It with Retaining Walls...................................................... 39 3.4 Option 2 – Remove the Box Culvert and Replace It with an Earthen Channel and Low Retaining Walls ............................................................................................................................................................... 41 3.5 Option 3 – Remove the Box Culvert and Replace It with an Earthen Channel .............................................. 43 3.6 Other Alternatives Evaluated .......................................................................................................................... 45 3.6.1 Leave the Box Culvert in Place and Daylight Base Flow ........................................................................ 45 3.6.2 Create an Open Channel Using the Box Culvert .................................................................................... 45 3.6.3 Create an Architectural Representation of the Underground Creek ....................................................... 46 3.6.4 “Do Nothing” ............................................................................................................................................ 46 3.7 Summary ......................................................................................................................................................... 47 2 FIGURES CRA DOWNTOWN ADVISORY BOARD Gigi Simmons, Chair Figure ES-1 Sweetwater Branch Creek Daylighting Conceptual Rendering .............................................................. 9 Kali Blount Figure ES-2 Sweetwater Branch Creek Daylighting Conceptual Rendering Cross-Section .................................... 10 Gracie Castine Figure ES-3 Sweetwater Branch Creek Daylighting Conceptual Renderings .......................................................... 11 Figure 1-1 Power District Conceptual Redevelopment Plan .................................................................................. 15 Jude Dawson Figure 2-1 Power District in 1937 ........................................................................................................................... 24 Adrian Hayes-Santos Figure 2-2 Power District in 1964 ..........................................................................................................................