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4. ECCSR 10-17-2007Lake Orono Dam Assessment Report Prepared for Elk River Municipal Utilities Elk River, Minnesota September 2007 4700 West 77th Street Minneapolis, MN 55435 BAR R phone: (952) 832-2600 Fax: (952) 832-2601 1.0 Introduction Elk River Municipal Utilities is considering redevelopment of hydroelectric generation at the Lake Orono Dam project. The Lake Orono Dam formerly generated electricity. It has been reported that the powerhouse formerly had two 150-KW generating systems. When the dam was rehabilitated in the early 1980s, all of the equipment was removed and the powerhouse intakes and outlets were filled with concrete. Presently the dam impounds water that creates Lake Orono that is a valuable regional resource. This report presents the results of a preliminary evaluation of issues related to redevelopment of hydroelectric generation. Redevelopment of hydroelectric facilities requires an economically viable site and careful attention to the permitting issues. The following sections present the results of preliminary assessment of the following categories: • Relicensing Process • Assessment of Generation Capability • Economic Factors • Summary and Conclusion P:\Mpls\23 MN\7]\237]089 Elk River Municipal-Orono Dam\WorkFiles\Report\Lake Orono Dam Assessment Report.doc 1 Based on our recent experience with the relicensing of a hydroelectric facility in Michigan, it is estimated that the process could cost between $500,000 and $2,000,000. The actual costs will be highly dependent upon the position of the stakeholders and the studies that are required. Attached as Appendix 2-2 are the table of contents and some selected sections from a Draft License Application for Minor Water Power Project, Minnesota Falls Hydroelectric Project, FERC Project No. 10336-00 and Initial Consultation Package Orienta Hydro Project FERC Project No. 10781-00. The City of Granite Falls held the preliminary permit for the Minnesota Falls dam at the time the draft license application was submitted. Dahlberg Light and Power Company was seeking the preliminary permit when the initial consultation package was submitted. These two documents provide examples of the level of effort that was required for these two projects and might represent the level of effort required for the Lake Orono Dam. P:\Mpls\23 MN\71\2371089 Elk River Municipal-Orono Dam\WorkFiles\Report\Lake Orono Dam Assessment Report.doc 3 4.0 Economic Factors Economic factors will be the overriding issue to determine the viability of the project. Development of hydropower is capital intensive to license, permit, and build the project. Once the project is completed and online, the ongoing operation and maintenance costs are minimal. Like wind power and landfill gas, the fuel is essentially free. However, the availability of the fuel to run the plant is generally outside of the Utilities' direct influence. The power plant would be run-of--river with a very narrow operating band on the headwater. Once the project is constructed and operational, power will be generated when water is available. Detailed costs for dam improvements and generating equipment have not been completed for this report. However, previous assessment of the equipment was completed by Elk River Municipal Utilities. Review of the costs indicates that they are on the low side. Based on our initial assessment of the project, we have developed a cost summary that is presented as Table 4-1 below. Values that were included in the ERMU cost estimate were based on the Engineering New Record (ENR) cost indices from 2000 to present. The cost of the turbine generator, electric feeder, switchgear, and to modify the discharge and riprap were increased for the upper bound value based on a ratio of the highest generation capacity/lowest generation capacity. Engineering was assumed to be 8% of construction. A contingency of 25% was added to the estimated total cost of permitting and construction. Table 4-1 Cost Summary Estimated Cost Item Description Lower Bound Upper Bound Permitting 1 Preliminary Filing to FERC $20,000 $50,000 2 Engineering Through RFQ $150,000 $250,000 3 Environmental Studies $500,000 `* $2,000,000 4 Follow-up Studies $80,000 $150,000 Subtotal Permitting $750,000 $2,450,000 Construction 5 Trash Racks " $25,000 $38,000 6 Clear Draft Tube " $65,000 $100,000 7 Modify Deck $30,000 $50,000 8 Modify Discharge and Riprap $95,000 $210,000 9 Turbine Generator $125,000 $280,000 10 Electric Feeder $30,000 $70,000 11 Switch Gear $30,000 $70,000 12 Engineering & Inspection (8%) $32,000 $65,000 Subtotal Construction Cost $432,000 $883,000 Subtotal $1,182,000 $3,333,000 Contingency (25%) $295,000 $833,000 Total $1,477,000 $4,166,000 * Source of cost is ERMU Cost Estimate 1/18/00 ''* Estimated to be in the range of P:\Ivlpls\23 MN\71\2371089 Elk River Municipal-Orono Dam\WorkFileslReport\Lake Orono Dam Assessment Report.doc 5 5.0 Summary and Conclusion Redevelopment of the Lake Orono Dam is dependent upon the requirements of state, federal, and local agencies, the cost of studies and construction, and the revenue the project can develop as well as the desire of the Elk River Municipal Utilities to redevelop the project. While the current sentiment is for renewable energy, regulations of water-based structures including dams and hydroelectric activities can be a detriment in the process. Two hydroelectric projects are currently in process for development in the city of Minneapolis. One is the Crown Mill site, located on the right bank adjacent to the St. Anthony Falls, Upper Lock and the other is the Lower St. Anthony Falls site, located on the left bank and to the left of the Lower St. Anthony Falls Lock and Dam. Both sites are located on the Mississippi River. Water rights differ between the two sites that will impact the volume of water that is available for generation. The upper Crown site has about 50 feet of head while the lower St. Anthony Falls site has about 25 feet of head. Neither site has an existing powerhouse or any other generation equipment. Development within the city of Minneapolis can be challenging, the Crown site has been in the development process for over a decade and the lower dam site has been idle since 1985 when the dam failed. These sites have favorable head (50 feet and 25 feet) and flow but still remain undeveloped- indicating the difficultly with the overall process. Development of Lake Orono for hydroelectric generation will be costly and may not have favorable economic factors. A preliminary net present worth of the annual revenue from generation ranges from $500,000 to $1,000,000 using an annual interest rate of 5% for a period of 20 years, and $600,000 to $1,370,000 for a period of 40 years. The range of estimated costs to permit and construct the project is $1,477,000 to $4,166,000. This initial cost estimate and assessment of revenue shows that the project will not provide a 20-year return on investment. These revenues and costs are highly variable and may change over time. The revenue/cost comparisons are meant to provide an order-of-magnitude comparison. If hydroelectric development at the Lake Orono Dam remains of interest to Elk River Municipal Utilities, the following are recommended: • Send a letter to the local, state, and federal stakeholders seeking their input regarding development of hydropower at the Lake Orono Dam. • Complete a Phase 1 inspection to determine the condition of the facilities and suitability for development. • Refine the selection of the turbine generator capacity/output. • Evaluate optional turbine generator supplies to better determine cost and required site modifications. • Revise the economic assessment to consider the revenue per Kw-hr and an annual interest rate for the capital expenditures. • Reassess the estimated cost and revenue. P:\Mp1s123 MN\71\2371089 Elk River Municipal-Orono Dam\WorkFiles\Report\Lake Orono Dam Assessment Report.doc 7