Hacker, Jester & Associates Rose-Hulman Institute of Technology 5500 Wabash Avenue Terre Haute, IN 47803 May 9, 2007 Geotechnical and Hydrologic Solutions Mr. Siavash E. Beik, P.E., CFM Christopher B. Burke Engineering, Ltd. 115 West Washington Street, Suite 1368 South Indianapolis, IN 46204 Dear Mr. Beik: Hacker, Jester & Associates has completed the inundation map for Crooked Creek Dam. To finish this task, the team collected hydrologic data and performed a hydrologic analysis on the watershed. We determined that the water overtops the dam by 2.7 feet during a 24-hr Probable Maximum Precipitation (PMP) using HEC-HMS. The team modeled a dam breach due to overtopping, which resulted in a peak reservoir outflow of 8,185 cfs. The outflow was used in HEC-RAS in conjunction with ArcGIS to create the inundation map. The team has also completed the slope stability analysis of Crooked Creek Dam. Available soil parameters and dam data were obtained from a report titled “Proposed Dam Rehabilitation Improvements – Crooked Creek Dam” (Burgess & Niple, 2004) and verified by us. With this information, we computed the factor of safety of the downstream slope stability using the program XSTABL. We found that the factor of safety is 1.80, which is considered acceptable since it is greater than 1.50. We enjoyed working with you and would like to thank you for considering us for this project and for your help throughout the analysis. Please contact us with any questions or comments you may have. Sincerely, Adam Hacker Chris Jester Project Manager Geotechnical Engineer Daniel Lexsa Matthew Mead GIS Technician Hydrology Engineer Richard Ballard Field EngineerFinal Report Crooked Creek Lake Dam: Dam Breach Analysis for Christopher B. Burke Engineering, Ltd. May 9, 2007 Hacker, Jester & AssociatesHacker, Jester, & Associates i Geotechnical and Hydrological Solutions DISCLAIMER The contents of this engineering design report were prepared by civil engineering students at Rose-Hulman Institute of Technology for their senior capstone design class. Hacker, Jester & Associates is a fictitious company created by these students (Adam Hacker, Chris Jester, Daniel Lexsa, Matthew Mead, and Richard Ballard) for the purpose of this class. These students are not registered professional engineers! All material presented herein should be reviewed and stamped by a professional engineer prior to construction. A liability waiver has been signed by the client, and copies are available from the client and from Rose-Hulman Institute of Technology.Hacker, Jester, & Associates ii Geotechnical and Hydrological Solutions Executive Summary Christopher B. Burke Engineering, Ltd. (CBBEL) is developing an Emergency Action Plan (EAP) for eighteen state-owned high hazard dams in Indiana. In the state of Indiana, a high hazard dam is defined as a dam whose failure would cause loss of life and/or significant property damage. To compile the EAPs, CBBEL selected Hacker, Jester and Associates to complete the key component, a detailed inundation map of Crooked Creek Lake Dam, located within Yellowwood State Forest so that our client could create an Emergency Action Plan. Yellowwood State Forest is in Brown County Indiana, which is approximately 50 miles south of Indianapolis. Hacker, Jester & Associates performed a breach analyses on the dam (sunny day and design flood), created downstream inundation maps, completed a slope stability analysis on the backside of the dam, and assessed different spillway design options to prevent the dam from overtopping during the design flood. The inundation map shows that the residential development south of the lake is not affected by the design storm during the dam breach. The design flood for this dam, as designated by the Indiana Department of Natural Resources, is the probable maximum flood (PMF) resulting from the 24-hour probable maximum precipitation (PMP). The hydrologic model result shows that the 24-hour PMP produces a peak outflow of over 19,000 cubic feet per second, a total outflow volume of over 800 acre-feet, and a peak storage of over 270 acre-feet during the PMP design storm. The results of the hydraulic model show that none of the three bridges will be overtopped in the event of a dam breach during either the sunny day or the PMP design storm. However, there were homes immediately downstream of the dam that will be flooded. The slope stability analysis shows that the dam is stable with a factor of safety of 1.80, which is greater than the required 1.50 factor of safety.Hacker, Jester, & Associates iii Geotechnical and Hydrological Solutions Table of Contents 1.0 Project Description 1 2.0 Design Requirements 2.1 Client Requirements 2.2 Constraints 2.3 Deliverables 4 4 5 3.0 Project Approach 6 4.0 Dam Failure Assessment 4.1 Codes and Regulations 4.2 Mapping 4.3 Hydrologic Data Collection 4.4 Hydrologic Modeling Results 4.5 Hydraulic Analysis 4.6 Inundation Mapping 4.7 Slope Stability Analysis 8 8 9 10 11 12 14 5.0 References 15 Appendices Appendix A: Codes and Regulations Appendix B: Mapping Appendix C: Hydrologic Data Collection Appendix D: Hydrologic Modeling Results Appendix E: Hydraulic Analysis Appendix F: Inundation Mapping Appendix G: Slope Stability AnalysisHacker, Jester & Associates 1 Geotechnical and Hydrologic Solutions 1. Project Description The Indiana Department of Natural Resources has contracted Christopher B. Burke Engineering, Ltd. (CBBEL) to prepare detailed dam breach inundation mapping for two of eighteen state-owned, high hazard dams in Indiana. Due to financial constraints, the remaining sixteen dams will receive breach inundation mapping that are based only on a “rule-of-thumb” flood wave height determination method. To make the most of the state funding that is available, CBBEL has contracted with Hacker, Jester & Associates to perform detailed dam breach analysis under their supervision on the Crooked