PSA - Lawson Fisher Associates - SB Dam Underwater Inspection & Bathymetric Survey

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APPENDIX 2 SCOPE OF WORK Project Understandine The Federal Energy Regulatory Commission (FERC) requires that an underwater inspection and a bathymetric survey be performed every ten (10) years at the South Bend Dam. The most recent underwater inspection was conducted in 2005 following the repair of the Dam. The next inspection was to be conducted in 2015 however the City was granted a one (1) year extension by the FERC. The summary report of the inspection and survey are due to the FERC by December 31, 2016. The following is LFA's scope of work for this project: 1. Coordinate with American Electric Power (AEP) regarding water release from the Twin Branch hydroelectric project. In the past AEP has been able to work within the FERC requirements to limit outflow from the Twin Branch project to allow for lower River flows during the underwater inspection and bathymetric survey. While this does not stop flow over the dam, the lower flow does allow for a safer inspection and survey. Coordination with AEP, the FERC and the Indiana Department of Natural Resources (IDNR) is required in order to manipulate the impoundment level upstream of the Twin Branch Dam. LFA will conduct this coordination as part of Task 1. 2. Coordinate and supervise the underwater inspection. LFA will work with the diving company (GUS Commercial Divers) to develop a plan for the underwater inspection of both the upstream and downstream faces of the dam. A video of the underwater inspection will be provided along a diver's report. Based on previous inspections, it is assumed that the underwater investigation will take only one 8-hour day to complete. 3. Perform bathometric survey downstream of dam. During previous inspections the riverbed downstream of the dam was surveyed to monitor the potential movement of river bed material. After several surveys it was concluded the river bed had stabilized and there appeared to be no threat to undermining of the Dam. In order to verify this conclusion, the FERC requires that this area be surveyed every ten (10) years. LFA will collect topographic survey data below the water surface in support of the monitoring of the river bottom conditions, just below the South Bend dam. The bathymetric data shall include: • Mass collection of river bottom grading features typical for creation of a surface model. • Analysis of latest surface model in comparison to the surface model of the same area created in 2000. • A report of findings based on the surface model comparison. 4. Prepare report for submittal to the FERC. LFA will prepare a report documenting the findings from both the underwater inspection and the bathymetric survey. LFA will submit the Report to the City for submittal to the FERC. Appendix 2, Scope of Work FJCDC E-520 Short Form of Agreement Between Owner and Engineer for Professional Services. Copyright CO2009 National Society of Professional Engineers for EJCDC. All rights reserved. Page 1