Sanitary Sewer #200 Area Flow Equalization Review of Project Design Criteria and Storage Options City of Northwood Planning Commission – Preliminary Site Plan Review Meeting – December 8, 2014 1
Project History City of Oregon Agreement with Ohio EPA Requires Various Improvements to Oregon System District Flows limited to 5 mgd District / City of Oregon Agreement Renewed April 2014 Flow Rate Limitation Maintained at 5 mgd New Requirements Flow Control Equipment Permanent Flow Metering 2 Million Gallons of Storage 18 months to Complete Improvements (October 2015) 2
Facility Planning Report (J&H) Existing Conditions 5 mgd rate exceeded 60+ times in 18 months* Recommendations I/I Removal & Reduction Flow Equalization Storage *Study Period from 1/2011 to 6/2012 3
Inflow and Infiltration (I/I) Reduction Repairs to the existing sewer system. District is committed to reducing I/I in the long term. I/I Reduction is not feasible in the short term. Costly – Estimated at over $20 million dollars. Time Consuming – I/I reduction schedule in years, not months. Results Uncertain – sealing leaks in one area often moves leak to another. Definitions: Inflow - Surface runoff directly entering Sanitary Sewer through illegally connected piping. Infiltration – Groundwater water entering pipe and manhole defects. 4
Why is Flow Equalization Storage Needed? To reduce wastewater pollution draining into Lake Erie. Wastewater from SS-200 Area goes to City of Oregon for Treatment. Average daily flow of 1 mgd. District is contract limited to 5 mgd into City of Oregon. Wet weather flow often exceeds 5 mgd. SS-200 contributes to Oregon’s overflows. City of Oregon has direct overflows into Lake Erie during extended wet weather. 5
How was Flow Equalization Site Selected? Near 48-inch Trunk Sewer Reduce Piping Costs Reduce Pumping Costs At downstream location on Trunk Sewer Optimize Operation – Basin requires sewer to surcharge to fill. Upstream of City of Oregon SS-200 Sanitary Sewer Service Area Existing Flow Control Structure City of Oregon Treatment on Curtice Road 6
How was Flow Equalization Site Selected? Enlarged Vicinity Map 7
How was Flow Equalization Site Selected? Profile of 48” Trunk Sewer 8
Flow Equalization Storage Options Above Grade Storage Basin Below Grade Storage Buried Pipeline Buried Structure 2.5 MG Basin – Terra Haute, IN 9
Below Grade Storage Pipeline Passive Operation – Fill / Drain by Gravity. Buried – No Above Grade Structure. Selected Alternative from Facility Planning Report. 10
Below Grade Storage Pipeline Preliminary Design Route Selected Considerations High Tension Electric Wetlands Construction Methods Preliminary Costs for the Storage Pipeline 11
Above Grade Storage 2.0 MG Prestressed Concrete Tank Pump Station for Filling Gravity Drain to 48” SS-200 Trunk Sewer Architectural Finish 2.1 MG Basin Butler County, OH 12
13 Above Grade Storage Basin
Economic / Financial Comparison Option 2 MG Storage 2 MG Above Grade Pipeline Basin Cost Savings Estimated Initial Project Cost $7,800,000 $5,100,000 $2,700,000 Estimated Annual O&M Cost* $37,400 $92,100 $(54,700) Estimated Annual Debt Service on Initial Project Cost (20 yrs at 3.1% APR – Ohio EPA DEFA Loan) $530,000 $340,000 $190,000 Estimated Total Annual Cost $567,400 $432,100 $135,300 *Includes Equipment Replacement Costs. 14
Operation & Maintenance Comparison Option / Criteria 2 MG Storage Pipeline 2 MG Above Grade Basin Land / Site Permanent Utility Easement Lands Purchased by District Operation Fill & Draw by Gravity Pumping to Fill Access Below Grade Above Grade Cleaning Outside Contractor Flushing Equipment & District Equipment Hydraulic Level and Flow Control Devices Pump Station & Telemetry (10MGD Capacity) Minimal Electric Power New 3 Phase Power for Pumps None Required Required for Pumps Backup Power Basement Flooding Due to Reduction in Minimal, excess flows to Oregon District Risk from Equipment Failure Sewer Freeboard Pays Flow Surcharge Site Maintenance Minimal Mowing / Landscaping Building Maint. Semi-annual Internal Inspection Annual Inspection Outside Utilities Toledo Edison & Sunoco Pipelines City of Northwood, Toledo Edison & Sunoco Pipelines Coordination Insurance Buried Pipe Above Grade Structure 15
Construction Schedule Comparison 2 MG Above Grade Task 2 MG Storage Pipeline* Basin NWSD / City Contract Effective Date April 2014 Final Design Complete October 2014 December 2014 Bidding May 2014 March 2014 Construction Commencement July 2015 June 2015 Construction Complete August 2016 January 2016 Contract Deadline for District Construction of Storage Improvements October 2015 All dates estimated as normal construction projects. Accelerated design and construction schedules may be possible at a cost premium. *The presented construction schedule based upon favorable pipe procurement. 16
17 Proposed View of Basin from Wise Street
Enlarged View of Proposed Basin from Wise Street 18
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