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Cleveland Public Library Photograph Collection. NEORSD. 62 Member Communities 1 Million People 370 Square Miles Ave. Daily Flow – 310 Million Gallons Combined Sewers - 35% Separate Sanitary Sewers - 65%. Sewer Overflow. Five Major Interceptor Systems. Northwest Interceptor
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NEORSD • 62 Member Communities • 1 Million People • 370 Square Miles • Ave. Daily Flow – 310 Million Gallons • Combined Sewers - 35% • Separate Sanitary Sewers - 65%
Five Major Interceptor Systems • Northwest Interceptor • Cuyahoga Valley Interceptor • Southwest Interceptor • Heights/Hilltop Interceptor • Mill Creek Tunnel
SYSTEM CAPITAL COST NORTHWEST INTERCEPTOR $25 MILLION SERVICE AREA MAP CUYAHOGA VALLEY INTERCEPTOR $75 MILLION SOUTHWEST INTERCEPTOR $210 MILLION $260 MILLION HEIGHTS/HILLTOP INTERCEPTOR MILL CREEK TUNNEL $150 MILLION
Mill Creek Tunnel Overview • Recommended in 1997 Facilities Plan • To be built under three contracts, MCT-1, 2, and 3 • 43,000 feet; 20 ft. Diameter; Depths up to 300 ft. • Estimated Construction Cost = $150 Million
Impacts of the Mill Creek Watershed Program • Provide over 70 million gallons of storage in new tunnel • Eliminate 13 overflows entirely (27 now exist) • Reduce annual overflow from over 500 million gallons to 14 million gallons • No remaining overflows should activate more than an average of 5 times per year
TBM Tunnel Boring Machine • Diameter – 23’ 8” • Length – 60’ / 200’ with trailing Gear • Weight – 700 tons • Production – 55’ / day / 8’ per hour • Spoils – 17 cubic ft. per linear foot • Cost - $10-15 million
Key Construction Issues • Blasting • Work Hours • Spoil Handling & Disposal
Key Construction Issue • Peak particle velocity held to less than 0.5 in/sec at nearest structures • Air-overburden Pressure Shall not Exceed 133 Decibels • Pre-Blast Survey Blasting
Key Construction Issue Blasting Placement of Charges Results at Surface Perception
Key Construction Issue Blasting Reality
Key Construction Issue Work Hours • Key concern to prospective bidders • Affects ability to construct shafts, mine tunnel, and remove spoils • One shift operation will add 1+ years and $5 million to the project
Key Construction Issue • Who owns the tunnel spoils? • 24’ diameter TBM produces 1400 cu.ft. of spoil material during 2/8 hour shifts. • 140 trucks per day • 12 trucks per hour • 1 truck every 5 minutes Spoil Handling & Disposal
Key Construction Issue Spoil Handling & Disposal • Volume of excavated material from MCT-2 70 feet high.
Key Construction Issue Spoil Handling & Disposal
Public Participation • Inform local officials of the project during the design process • Keep local officials informed during design & discuss issues that impact the local community • Convene public meetings prior to the commencement of construction
Easterly Facilities Plan • 88,300 of 18’-24’ tunnels • 27 shafts • 160 MGD pump station • Total estimated projected cost - $1.3 billion
Impacts of Proposed Easterly Projects • Provide 152 million gallons of storage in new tunnel • Eliminate 78 high-maintenance regulators reducing the potential for dry weather discharges • Reduce annual overflow from 2,560 million gallons to about 450 million gallons • No remaining overflows should activate more than an average of 4 times per year
Funding • Water Pollution Control Loan Fund (WPCLF) • Administered by Ohio EPA • Low Interest Loan Program • Standard Construction Loan – 20 year based on 1.25% discount below the current GO bond – currently 3.78% • NEORSD has received 33 loans representing $387 million • WPCLF has financed 53% of District jobs since 1991