Task 1: Review of Available Reports & Information and Data Collection The Consultant shall review the existing data and reports from previous investigations of Pine Hill Reservoir Dam. Documents of this type are included in Appendix A. The Consultant shall create a plan for the collection of field data not already compiled and deliver it to the DPW&P for review. Additional field data that is reasonably expected to be collected includes: • Wetland delineation and survey in accordance with local, state, and federal regulations. Wetland delineation and survey shall also include the access driveway from end to end in anticipation of it needing to be reconstructed as part of the dam project. • Topographic survey of the dam and the immediate area. Topographic survey shall also include the access driveway for the purposes described above. • Dam and spillway inspections. • Concrete assessment including vertical coring to assess internal conditions. Horizontal coring to assess the condition of both the upstream and downstream integrity. It is anticipated that laboratory testing will be required to adequately assess concrete type and compressive strength. • Earthen embankment inspection including soil borings. • Underwater inspection of the dam. • Pipe inspections of both outlet pipes and seepage pipes/galleries. • Bathymetric survey of the of the upstream and downstream areas. The width and depth of the survey shall be enough to establish underwater slope geometries. Task 2: Pre-design Following the completion of Task 1, the Consultant will provide the DPW&P with an assessment summary of the Consultant’s findings. This summary shall include: • Summary of collected reports and data collection. • Existing conditions summary report with plans & sections showing deficiencies. • A ranking of deficiencies relative to severity and criticality. • Concept approaches to addressing the identified deficiencies. • Hydrologic and Hydraulic Analysis using the most up to date land use, topographic, and rainfall data. Task 3: Alternatives Analysis The Consultant shall create an alternatives analysis addressing the deficiencies identified in the predesign summary. The alternatives analysis, preferred approach, conceptual design, and opinion(s) of probable cost shall be provided to the DPW&P for review. It is expected that the Consultant shall engage with the DPW&P with at least three meetings to determine the selected alternative. The alternatives analysis should consider the following key design elements items: • Upstream face repairs. • Downstream face repairs. • Spillway repairs. • Seepage gallery improvements. • Slope and gravity stability improvements. • Mechanical equipment repair or replacement. • Dam operability improvements (level controls, gate operation, access, safety, security, telemetry, etc. • Vegetation control / clearing / maintenance. • Aesthetic consideration. • Permit considerations for the selected design and its environmental impacts and cost. • Post-construction access road restoration. • Other. Opinion of Probable Cost(s): Project costs shall be identified by project component described above or by other components discovered during the design. The Consultant shall use bid values of recently completed projects, manufacturer’s quotes, cost estimating guides, and the Consultant’s experience to determine cost estimates.
