Minneapolis Fridley Filter Plant Split

Transcription

1 Minneapolis Fridley Filter Plant Split Surface Water Treatment Workshop April 29 May 1, 2014 Fargo, ND Today s Presentation Fridley Filter Plant (FFP) History & Overview Why FFP split project? Project overview Planning efforts before construction Construction phase 1

2 History 1910 to 1913 Filtration plant construction at Columbia Heights site 1925 Filtration plant at Fridley site 1940 Lime softening plant at Fridley site 2005 C.H. membrane plant (CHMP) in service 2013 Upgrades to FFP begin Phase 1: FFP Split Project Phase 2: Fridley Filter Rehabilitation Process Schematic Mississippi RIVER MIX SOFTENING RECARB. PUMP Fridley campus.... MIX COAG / SETTLE RESERVOIRS (and Distribution to Customers) RESERVOIR MIX COAG / SETTLE PUMP Columbia Heights campus ULTRAFILTRATION RESERVOIRS (and Distribution to Customers) 2

3 System Capacity Population served = 500,000 Fridley Softening Plant (Total Capacity) = 160 MGD CHMP Capacity = 75 MGD (summer) = 40 MGD (winter) FFP Capacity = 120 MGD Average Daily Demand = 60 MGD Project Drivers To improve operational redundancy Rehabilitate filters (with GAC in 2 phases) keeping half of the plant in service To enable taking portions of the plant out of service for other repairs and maintenance 3

4 Project Overview Lower Level 66 AND 84 PIPES FROM PS NO 6 FILTERED WATER CONDUIT VALVE 182 VALVE 183 REMOVE EXISTING GATE N CONTROL CHAMBER VENTURI CHAMBER WEST CLEARWELL MIXING CHAMBERS COAG 2 COAG 3 BY-PASS VALVE EAST CLEARWELL ILTERS F ILTERS F COAG 1 COAG 4 FILTERED WATER CONDUIT LEGEND NEW GATE (5 X5 ) NEW WALL NEW SEGMENTAL WALL Project Overview Upper Level FILTER INFLUENT WATER CONDUIT N COAG WATER CONDUIT S S MIXING CHAMBERS COAG 2 COAG 3 VOID REMOVE EXISTING GATES AND SEAL ALL OPENINGS F F COAG 1 COAG 4 FILTER INFLUENT WATER CONDUIT LEGEND NEW GATE NEW WALL NEW STOP LOGS 4

5 Project Overview Lower Level 66 AND 84 PIPES FROM PS NO 6 FILTERED WATER CONDUIT VALVE 182 VALVE 183 N CONTROL CHAMBER VENTURI CHAMBER WEST CLEARWELL MIXING CHAMBERS COAG 2 COAG 3 BY-PASS VALVE EAST CLEARWELL ILTERS F ILTERS F COAG 1 COAG 4 FILTERED WATER CONDUIT LEGEND NEW GATE (5 X5 ) NEW WALL NEW SEGMENTAL WALL NEW STOP LOGS Project Overview Critical phase construction Construction of approx. 500 feet of concrete dividing walls Modifications to water treatment chemical feed system Installation of 5 slide gates and 6 stop log gates Structural surface rehabilitation considered noncritical phase construction 5

6 Bringing C.H. Filter Plant On-line Why? Extended FFP shut down needed for FFP Split construction CHMP capacity (Nov. to Jan.): mgd Water demand (Nov. to Jan.): mgd Preparation work Checked manually-operated valves for each filter. 17 out of 24 filters available for service Recommissioned turbidimeters for each filter. Addressed post treatment. Notified MDH. Planning Efforts Before Construction Engineer: CH2M Hill Contractor: Municipal Builders, Inc (MBI) Subcontractor: PciRoads Hazardous analysis & notification of Minneapolis Fire Dept. Confined space Hazardous chemicals (Cl 2, NH 3 ) Coordination with MWW operations & detailed LOTO procedures Detailed site walkthrough to discuss the construction process Detailed day-to-day construction schedule from MBI 6

7 Construction Timeline Sept 30, 2013 Dec 13, 2013: Critical phase construction and elective concrete repair/crack injection work Critical phase construction completed in 37 days Jan. 2014: FFP restarted Jan Apr. 2014: Remaining concrete repair/crack injection work & misc. other work Apr. 2014: 95% of construction complete Concrete Dividing Wall Construction Adverse construction condition Confined space Ventilation requirements Lighting requirements 5-ft tall finished water conduit On-site construction manager from CH2M Hill performs quality control & special inspections 28-day cast-in-place concrete strengths: Requirements: 4,500 psi Testing results: 5,500 psi 7

8 Concrete Dividing Wall Construction Control Chamber Divider Wall (41 long x 18 tall) Upper Flume Divider Wall (96 long x 10 tall) Finished Water Conduit Divider Wall (300 long by 5 tall) Chemical Feed System Modifications Double feed in the finished water conduit (poly, Cl 2, Fluoride) New instruments for CFE and PE monitoring on the west side SCADA integration of the new instruments by In Control, Inc. New CFE and PE sampling pumps Essentially two separate plant effluents 8

9 Chemical Feed and Sampling Before-Split Scheme Chemical Feed and Sampling Post-Split Scheme 9

10 Chemical Feed System Modifications East/West Poly, Cl2, Fluoride Feed Systems New CFE Sample Pumps Slide Gates and Stop Log Gates Installation 5 slide gates and 6 stop log gates Build outs for battered wall Mixing Chamber Slide Gate Upper Flume Stop Log Gate 10

11 Slide Gates and Stop Log Gates Installation New Control Chamber Slide Gate Old Control Chamber Influent Gate Removal of Coagulation Basin No. 5 Demolition of Coag Basin No. 5 Backfill with granular fill 11

12 Structural Surface Rehabilitation Quantities: Wall repair: 530 ft 2 Slab repair: 1,650 ft 2 Crack/Joint Repair: 2,360 ft Utilized plant shut down for 80% of concrete repair/crack injection work Structural Surface Rehabilitation FWC Pre-project 10,000 psi high pressure water wash Rehabilitated FWC 12

13 Structural Surface Rehabilitation Removal of Loose and Delaminated Concrete Reinforcing Rebar Crack Repair FFP Split Project Operational redundancy achieved Aggressive yet flexible schedule met Safety issues for challenging construction conditions addressed Looking forward to 75 more years of effective filter operations 13

14 Questions? Annika Bankston Li Zhang