Easterly Tunnel Dewatering Pump Station

Presented by: Michael Ritossa, MWHAnna Santino, MWHEasterly Tunnel DewateringPump StationJune 19, 2012

OUTLINE• Project Technical Overview• Pump Design and Operation• Architectural and Pump Station SupportFacilities• Below Grade Facilities• Geotechnical2

Project Technical Overview3

Consent Decree Requires 98%Capture of CSO Volume by 20364Combined Sewer Area

126 CSO Locations Throughoutthe Combined Sewer Area areDriving a Systematic Approachto Mitigate Overflows

6Project Clean Lake – Easterly Service AreaEasterly ServiceArea Includes:• Five Tunnels• DewateringPump Station• AncillaryConsolidationSewers• RegulatorImprovementsTunnelDewateringPump Station

7The Nine Mile SiteWill Be the Nexus ofSeven Projects:Easterly WWTPDWIRS $64MECT $200MDST $150METDPS $70ME. 140 th $41MSubstation $5MEuclid Creek PS $11M$541MCity ofClevelandVillage ofBratenahlECTETDPS

E. 140 th Street8Nine Mile Project Site is Accessedfrom East 140 th StreetETDPSSTAGINGAREAETDPSPROJECTSITE

3D Rendering From AboveECT Shaft 1ElectricalSubstation9

Northeast Corner10

ETDPS Project Technical Overview1. Cavern Style Pump Station• 160 MGD Firm Capacity• 230 +/- Feet Deep2. Receives Flows from 3 Storage Tunnels:• Euclid Creek 61MG• Dugway 51MG• Shoreline 48 MG3. Delivers Flows to Easterly Interceptor• Gravity Delivery to Easterly WWTP• Easterly Flow Management Important11

Below-Ground Facilities12

ETDPS Programmed to be CompleteShortly After ECT is Activated and Readyto Accept Flows.Project2011 2012 2013 2014 2015 2016 2017Euclid Creek Storage TunnelApr 2011 4 years duration Apr 2015SHORT PERIOD TO FINALIZE WORKTunnel Dewatering Pump StationJan 2012 3 years 6 months duration Jun 2015Dugway Storage TunnelSep 20154 years durationETDPS must coordinate w/ ECT for final connections:• Install Roller Gate• Final Adit Connection• Pump Testing and Commissioning13

Pump System:Pumped Flow & Hydraulic Design14

Pump Design and Operation - Objectives1. Meet Requirements of Consent Decree2. Cost-Effective, Reliable System3. Operability/Maintainability Considerations• Collection/Tunnel System• Pump Station• Easterly15

Pump Design and Operation - Components1. Main Dewatering Pumps• 4 @ 40 MGD• 1 @ 20 MGD2. Final Dewatering Pumps• 2 @ 10 MGD3. Valves• Suction (Isolation)A. Knife Gate Valves (5 Main Dewatering Pumps)B. Plug Valves (2 Final Dewatering Pumps)• Discharge (Isolation/Flow Control)A. Hydraulically Operated Cone Valves4. Emergency Sump Pumps• 2 @ 1 MGD16

Cone Valve - ThrottlingKey Hydraulic Elevations – Tunnel and Pump StationSystemECT/DSTSTORAGE (MG)Tunnels will fill to HWLEL. 575 about 3 timesin an average yearThrottled Operation30 hours/yr @ 160 mgd[0.2 BG volume]10% of operating volumeUn-throttled Operation303 hours/yr @ 160 mgd[2 BG volume]90% of operating volumeEL 412 (7.8 MG)SHUT OFF20/40 MGDTop of Header NormallySubmerged at End ofPumping CycleINV EL 402.751717

Final Dewatering PumpsSuctionHeaderPlug ValveEmerg.SumpPumpsMain Dewatering Pump Suction LinesELEV. 369Knife GateValveMain Dewatering Pumps & MotorsELEV. 38918

Separate Discharge Headers Were Provided to MaintainMinimum Velocities and Minimize Solids Accumulation19

Pump Room - Floors AddedMezzanineUpper LevelLower Level20

Ventilation Designed to Avoid Hazardous Classification(i.e. Explosion Proof Devices)• Occupied: 6 Air Changes• Unoccupied: 6 Air Changeswith 75% Recirculation21

Pump Room - Entire Structure Added• Cast-in-Place Concrete forShafts• Shotcrete in Pump RoomWalls and Roof22

Consideration was Given to Ensure AdequateSpace for Maintenance and RepairPump Room Looking East – Elev. 36923

Pump Room Looking East - Elevs. 389 & 40024

Pump Room Looking West - Elevs. 389 & 40025

West End of Pump Room - Elevs. 389 & 40026

Pump Design and Operation – CFD ModelPhase 1Phase 2The Original Model showedtwo of four pumps couldexperience adverse flowconditions of pre-swirl andaxial velocity deviation.The model was revised byadding straightening vanesand adding reducing typebends.27

Flow DirectionCFD Modeling Confirmed Need For FlowStraightening VanesVanes are Shaped tobe “Self-cleaning”28

Main Dewatering Pump SupportsFinite Element Analysis of Pump Supports were used for Vibration Analysis29

Architectural and Pump StationSupport Facilities30

Architectural and Pump StationSupport FacilitiesSuperstructure Contains:• Materials Handling Features• Electrical, Communicationsand Control Rooms• Hydraulic Room• Maintenance-RelatedRooms• Rest Rooms31

Pump Building Plan - Architectural32

Pump Building at Grade - Roof Removed33

Material Handling12’x12’ roof hatch providesaccess for wheel or trackmounted crane to movelarge equipment to andfrom cavern.5 Ton Jib Crane designed tolift mid sized items to atgradefloor level 609.034

Below Grade Facilities35

Below-Ground Facilities36

Access Shafts - Looking North37

Below-Ground Facilities38

CavernHeight68 FtPrimary Shaft Support in OverburdenSteel Liner Plate and Steel Ribs on 4” COCSpacing.Primary Shaft Support in RockRock Dowels in 6’ x 6’ Pattern with 2” Thick Layer ofShotcrete (WWM or Fiber-Reinforced) . 4” ThickShotcrete for 20’ Zone above Cavern Roof.Cavern and Access Shaft Dimensions39

Geotechnical40

Access Shafts - Looking NorthSoil95 FtRock130 Ft41

Current Principal Topics of GeotechnicalEvaluation• Permanent structural support– Rock bolt lengths, diameter, spacing– Shotcrete thickness, strength, reinforcing• Long term stability of shale– Slaking• Long term durability of permanent support– Corrosion of steel– Deterioration of shotcrete• Permanent drain system– Drain spacing– Encrustation prevention42

Rock Bolt/Dowel Pattern – Cavern Roof and Walls297 Dowels 487 Bolts 306 Dowels5’ x 5’ DowelPattern onWalls5’ x 4’ BoltPattern onRoof andHaunches w/Add’l Bolts @ShaftsTwo 2” Thick Layers of Reinforced Shotcrete onWalls with a Layer of Non-ReinforcedSmoothing Shotcrete on Lowest 10’Two 3” Thick Layers ofReinforced Shotcrete onRoof and Haunches43

Rock Dowel Pattern – Cavern Floor270 Dowels5’ x 5’ DowelPattern onFloor44

Raw Water Tunnel45

Questions?49