City of Greencastle Flood Protection Plan Presented by, United Geotech, LTD

Introduction Team Overview Project Overview Design Requirements Project Approach Final Design Questions

Team Overview Sarah Bireley– Project Manager Amee Wicks – Project Engineer Brad Pickering – Project Engineer Troy Cunat – Project Engineer

Project Overview Greencastle Water Treatment Plant Located in Greencastle, Indiana south of Big Walnut Creek Six wells provide 4,000 gpm peak Serves population of 10,000 Site subject to flooding Located in the flood plain Rains on Labor Day flooded site

Project Overview (cont.) Well field Big Walnut Creek Filter Facility Lagoon US-231

Project Overview (cont.) Taken September 16, 2003 Taken September 2, 2003

Design Requirements Confirm finished floor elevation of filter facility Confirm base flood elevation Investigate flood protection options Investigate security options Deliverables Proposal Progress report Final report

Project Approach Site assessment Codes and regulations Research design options Flood protection Security Choose final design Complete final design

Site Assessment Topographic map Finished floor elevation = feet (MSL) Filter Facility Lagoon Big Walnut Creek

Site Assessment (cont.) Watershed area obtained 216 mi 2 Determined base flood elevation Obtained Big Walnut Creek topographic map 100-year flow determined Q = 21,400 cfs Maximum flows used in HEC-RAS to determine base flood elevation feet (MSL)

Site Assessment (cont.)

Low head dam Finished floor elevation

Codes and Regulations Cannot raise base flood elevation more than 0.15 feet Water tower must be enclosed in fence Maximum levee side slope of 1:2.5 No levee construction restrictions

Design Options Flood control options Levee under construction Floodwall under construction

Design Options (cont.) Flood control options (cont.) Elevated structure Dry floodproofing

Design Options (cont.) Initial Cost (35%) Lifespan (35%) Maintenance (20%) Constructability (20%) Overall Levee Floodproofing Floodwall Building Relocation Decision based on four criteria Initial cost Lifespan Maintenance Constructability

Levee Design Obtained soil borings & performed tests Clay (CH), silt (MH), and sand (SW) present Suitable for levee B1 B2 B3 B4 B5 B6

Levee Design (cont.) Lagoon Expansion Filter Facility

Levee Design (cont.) Levee cross sections

Seepage Analysis Used SefDam to calculate seepage Elev. 692’ 13’ Elev. 690’ SectionPermeability (ft/s)Height (ft)Width (ft)Seepage (ft 3 /s/ft) A-A’3 x x B-B’3 x x C-C’3 x x D-D’3 x x E-E’3 x x Total seepage is ft 3 /day

Slope Stability

Slope Stability (cont.) XSTABL utilized to analyze slope stability Eroding slope improved by Greencastle Additional load from levee analyzed Additional load does not cause failure

Security Fencing, lighting, and cameras investigated Lighting and cameras may be added in future Initial Cost (30%) Lifespan (30%) Maintenance (20%) Protection (20%) Overall Chain Link Fence with Barbed Wire Color Weatherproof Camera Infrared Sensor Lights

Security (cont.) Filter Facility

Cost R.S. Means Manual used to estimate costs Levee $71,500 Security $24,000 Total cost $95,500

Conclusion Flood levels warrant need for flood protection Levee chosen as protection option Seepage and slope stability not a problem Fencing with barbed wire chosen for security Cameras and lighting may be added Total cost of $95,500 Levee - $71,500 Security - $24,000

Questions???