![Page 1: A Gravity Situation Eastside Trunk Sewer · 5/5/2017 · regional WWTP • ADWF: 3.3 mgd • PWWF: 14 mgd . A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA ... •](https://reader036.vdocuments.us/reader036/viewer/2022071008/5fc611d279ca866bca5fd214/html5/thumbnails/1.jpg)
A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA
A Gravity Situation –
Eastside Trunk Sewer
Rohnert Park, CA
Art da Rosa, PE | Civil Engineer | City of Rohnert Park
Matt Winkelman, PE | Civil Engineer | GHD Inc.
Jim Winter, PE | Construction Manager | GHD Inc.
Dru Nielson, CEG | Geologist | McMillen Jacobs Associates
![Page 2: A Gravity Situation Eastside Trunk Sewer · 5/5/2017 · regional WWTP • ADWF: 3.3 mgd • PWWF: 14 mgd . A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA ... •](https://reader036.vdocuments.us/reader036/viewer/2022071008/5fc611d279ca866bca5fd214/html5/thumbnails/2.jpg)
A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA
Presentation agenda
• Background
• Planning and Design
• Construction
• Conclusions and What’s Next
![Page 3: A Gravity Situation Eastside Trunk Sewer · 5/5/2017 · regional WWTP • ADWF: 3.3 mgd • PWWF: 14 mgd . A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA ... •](https://reader036.vdocuments.us/reader036/viewer/2022071008/5fc611d279ca866bca5fd214/html5/thumbnails/3.jpg)
Background
![Page 4: A Gravity Situation Eastside Trunk Sewer · 5/5/2017 · regional WWTP • ADWF: 3.3 mgd • PWWF: 14 mgd . A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA ... •](https://reader036.vdocuments.us/reader036/viewer/2022071008/5fc611d279ca866bca5fd214/html5/thumbnails/4.jpg)
A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA
Rohnert Park
• Located in Sonoma County
• Population ~ 45,000
• Incorporated in 1962
City of Rohnert Park, California
![Page 5: A Gravity Situation Eastside Trunk Sewer · 5/5/2017 · regional WWTP • ADWF: 3.3 mgd • PWWF: 14 mgd . A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA ... •](https://reader036.vdocuments.us/reader036/viewer/2022071008/5fc611d279ca866bca5fd214/html5/thumbnails/5.jpg)
A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA
Rohnert Park collection system - overview
• 80 miles of 6- to 42-inch gravity sewer
• 16 inverted siphons
• 1 collection system lift station
• All flow conveyed to Main Pump Station, which pumps flow to the
regional WWTP
• ADWF: 3.3 mgd
• PWWF: 14 mgd
![Page 6: A Gravity Situation Eastside Trunk Sewer · 5/5/2017 · regional WWTP • ADWF: 3.3 mgd • PWWF: 14 mgd . A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA ... •](https://reader036.vdocuments.us/reader036/viewer/2022071008/5fc611d279ca866bca5fd214/html5/thumbnails/6.jpg)
A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA
Rohnert Park collection system goals
• Minimize the use of pump stations
• Reduce life cycle costs associated with I/I
• Improve collection system reliability
• Build critical infrastructure with a longer useful life compared to local
collector sewers
• Minimize impacts to the public
![Page 7: A Gravity Situation Eastside Trunk Sewer · 5/5/2017 · regional WWTP • ADWF: 3.3 mgd • PWWF: 14 mgd . A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA ... •](https://reader036.vdocuments.us/reader036/viewer/2022071008/5fc611d279ca866bca5fd214/html5/thumbnails/7.jpg)
A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA
System evaluation: 2003 - 2005
• Flow monitoring and field reconnaissance
• Hydraulic modeling and assessment
• Hydraulic deficiencies identified
• Opportunity identified to alleviate deficiencies by constructing a new,
gravity trunk sewer
![Page 8: A Gravity Situation Eastside Trunk Sewer · 5/5/2017 · regional WWTP • ADWF: 3.3 mgd • PWWF: 14 mgd . A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA ... •](https://reader036.vdocuments.us/reader036/viewer/2022071008/5fc611d279ca866bca5fd214/html5/thumbnails/8.jpg)
A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA
System evaluation: the result
• Construct a 3.5 mile trunk sewer to relieve capacity deficiencies in
the eastern portion of the collection system
• Convey up to 12.7 mgd to the Main Pump Station
• Project split into three phases
![Page 9: A Gravity Situation Eastside Trunk Sewer · 5/5/2017 · regional WWTP • ADWF: 3.3 mgd • PWWF: 14 mgd . A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA ... •](https://reader036.vdocuments.us/reader036/viewer/2022071008/5fc611d279ca866bca5fd214/html5/thumbnails/9.jpg)
A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA
Rohnert Park trunk sewers
![Page 10: A Gravity Situation Eastside Trunk Sewer · 5/5/2017 · regional WWTP • ADWF: 3.3 mgd • PWWF: 14 mgd . A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA ... •](https://reader036.vdocuments.us/reader036/viewer/2022071008/5fc611d279ca866bca5fd214/html5/thumbnails/10.jpg)
A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA
Eastside trunk sewer (2008-2015)
![Page 11: A Gravity Situation Eastside Trunk Sewer · 5/5/2017 · regional WWTP • ADWF: 3.3 mgd • PWWF: 14 mgd . A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA ... •](https://reader036.vdocuments.us/reader036/viewer/2022071008/5fc611d279ca866bca5fd214/html5/thumbnails/11.jpg)
Planning and Design
![Page 12: A Gravity Situation Eastside Trunk Sewer · 5/5/2017 · regional WWTP • ADWF: 3.3 mgd • PWWF: 14 mgd . A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA ... •](https://reader036.vdocuments.us/reader036/viewer/2022071008/5fc611d279ca866bca5fd214/html5/thumbnails/12.jpg)
A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA
Geotechnical Setting
Berkeley
Rohnert Park
![Page 13: A Gravity Situation Eastside Trunk Sewer · 5/5/2017 · regional WWTP • ADWF: 3.3 mgd • PWWF: 14 mgd . A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA ... •](https://reader036.vdocuments.us/reader036/viewer/2022071008/5fc611d279ca866bca5fd214/html5/thumbnails/13.jpg)
A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA
Geotechnical Setting
![Page 14: A Gravity Situation Eastside Trunk Sewer · 5/5/2017 · regional WWTP • ADWF: 3.3 mgd • PWWF: 14 mgd . A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA ... •](https://reader036.vdocuments.us/reader036/viewer/2022071008/5fc611d279ca866bca5fd214/html5/thumbnails/14.jpg)
A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA
Geotechnical Setting
![Page 15: A Gravity Situation Eastside Trunk Sewer · 5/5/2017 · regional WWTP • ADWF: 3.3 mgd • PWWF: 14 mgd . A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA ... •](https://reader036.vdocuments.us/reader036/viewer/2022071008/5fc611d279ca866bca5fd214/html5/thumbnails/15.jpg)
A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA
Geotechnical Setting
![Page 16: A Gravity Situation Eastside Trunk Sewer · 5/5/2017 · regional WWTP • ADWF: 3.3 mgd • PWWF: 14 mgd . A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA ... •](https://reader036.vdocuments.us/reader036/viewer/2022071008/5fc611d279ca866bca5fd214/html5/thumbnails/16.jpg)
A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA
Geotechnical Setting
![Page 17: A Gravity Situation Eastside Trunk Sewer · 5/5/2017 · regional WWTP • ADWF: 3.3 mgd • PWWF: 14 mgd . A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA ... •](https://reader036.vdocuments.us/reader036/viewer/2022071008/5fc611d279ca866bca5fd214/html5/thumbnails/17.jpg)
A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA
A Gravity Situation
• What is the challenge?
• Is construction feasible?
• Does the project make financial sense?
• What are the project/municipality objectives?
• Comprehensive planning, then design
![Page 18: A Gravity Situation Eastside Trunk Sewer · 5/5/2017 · regional WWTP • ADWF: 3.3 mgd • PWWF: 14 mgd . A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA ... •](https://reader036.vdocuments.us/reader036/viewer/2022071008/5fc611d279ca866bca5fd214/html5/thumbnails/18.jpg)
A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA
Gravity trunk sewers
• Utility conflicts
• Highway, railroad, and waterway crossings
• Flat and/or hilly terrain – deep trenching
• High groundwater and poor soils
• Community impacts
![Page 19: A Gravity Situation Eastside Trunk Sewer · 5/5/2017 · regional WWTP • ADWF: 3.3 mgd • PWWF: 14 mgd . A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA ... •](https://reader036.vdocuments.us/reader036/viewer/2022071008/5fc611d279ca866bca5fd214/html5/thumbnails/19.jpg)
A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA
An alternative – pumped system
• Shallower trenching
• Fewer potential utility conflicts
However…
• Pump station capital and O&M costs
• Local collection system needs
• Community impacts
![Page 20: A Gravity Situation Eastside Trunk Sewer · 5/5/2017 · regional WWTP • ADWF: 3.3 mgd • PWWF: 14 mgd . A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA ... •](https://reader036.vdocuments.us/reader036/viewer/2022071008/5fc611d279ca866bca5fd214/html5/thumbnails/20.jpg)
A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA
Gravity or pumped system?
• Useful life of construction materials
• O&M costs
• System reliability
![Page 21: A Gravity Situation Eastside Trunk Sewer · 5/5/2017 · regional WWTP • ADWF: 3.3 mgd • PWWF: 14 mgd . A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA ... •](https://reader036.vdocuments.us/reader036/viewer/2022071008/5fc611d279ca866bca5fd214/html5/thumbnails/21.jpg)
A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA
![Page 22: A Gravity Situation Eastside Trunk Sewer · 5/5/2017 · regional WWTP • ADWF: 3.3 mgd • PWWF: 14 mgd . A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA ... •](https://reader036.vdocuments.us/reader036/viewer/2022071008/5fc611d279ca866bca5fd214/html5/thumbnails/22.jpg)
A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA
![Page 23: A Gravity Situation Eastside Trunk Sewer · 5/5/2017 · regional WWTP • ADWF: 3.3 mgd • PWWF: 14 mgd . A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA ... •](https://reader036.vdocuments.us/reader036/viewer/2022071008/5fc611d279ca866bca5fd214/html5/thumbnails/23.jpg)
A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA
![Page 24: A Gravity Situation Eastside Trunk Sewer · 5/5/2017 · regional WWTP • ADWF: 3.3 mgd • PWWF: 14 mgd . A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA ... •](https://reader036.vdocuments.us/reader036/viewer/2022071008/5fc611d279ca866bca5fd214/html5/thumbnails/24.jpg)
A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA
LOW I/I / Corrosion / Community Impacts HIGH
![Page 25: A Gravity Situation Eastside Trunk Sewer · 5/5/2017 · regional WWTP • ADWF: 3.3 mgd • PWWF: 14 mgd . A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA ... •](https://reader036.vdocuments.us/reader036/viewer/2022071008/5fc611d279ca866bca5fd214/html5/thumbnails/25.jpg)
A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA
LOW I/I / Corrosion / Community Impacts HIGH
![Page 26: A Gravity Situation Eastside Trunk Sewer · 5/5/2017 · regional WWTP • ADWF: 3.3 mgd • PWWF: 14 mgd . A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA ... •](https://reader036.vdocuments.us/reader036/viewer/2022071008/5fc611d279ca866bca5fd214/html5/thumbnails/26.jpg)
A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA
LOW I/I / Corrosion / Community Impacts HIGH
![Page 27: A Gravity Situation Eastside Trunk Sewer · 5/5/2017 · regional WWTP • ADWF: 3.3 mgd • PWWF: 14 mgd . A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA ... •](https://reader036.vdocuments.us/reader036/viewer/2022071008/5fc611d279ca866bca5fd214/html5/thumbnails/27.jpg)
A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA
Corrosive atmosphere in manhole
Unlined manhole Fiberglass base liner
![Page 28: A Gravity Situation Eastside Trunk Sewer · 5/5/2017 · regional WWTP • ADWF: 3.3 mgd • PWWF: 14 mgd . A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA ... •](https://reader036.vdocuments.us/reader036/viewer/2022071008/5fc611d279ca866bca5fd214/html5/thumbnails/28.jpg)
A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA
Lined or unlined manholes?
![Page 29: A Gravity Situation Eastside Trunk Sewer · 5/5/2017 · regional WWTP • ADWF: 3.3 mgd • PWWF: 14 mgd . A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA ... •](https://reader036.vdocuments.us/reader036/viewer/2022071008/5fc611d279ca866bca5fd214/html5/thumbnails/29.jpg)
A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA
Lined or unlined manholes?
![Page 30: A Gravity Situation Eastside Trunk Sewer · 5/5/2017 · regional WWTP • ADWF: 3.3 mgd • PWWF: 14 mgd . A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA ... •](https://reader036.vdocuments.us/reader036/viewer/2022071008/5fc611d279ca866bca5fd214/html5/thumbnails/30.jpg)
A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA
Lined or unlined manholes?
![Page 31: A Gravity Situation Eastside Trunk Sewer · 5/5/2017 · regional WWTP • ADWF: 3.3 mgd • PWWF: 14 mgd . A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA ... •](https://reader036.vdocuments.us/reader036/viewer/2022071008/5fc611d279ca866bca5fd214/html5/thumbnails/31.jpg)
A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA
Lined or unlined manholes?
![Page 32: A Gravity Situation Eastside Trunk Sewer · 5/5/2017 · regional WWTP • ADWF: 3.3 mgd • PWWF: 14 mgd . A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA ... •](https://reader036.vdocuments.us/reader036/viewer/2022071008/5fc611d279ca866bca5fd214/html5/thumbnails/32.jpg)
A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA
Lined or unlined manholes?
![Page 33: A Gravity Situation Eastside Trunk Sewer · 5/5/2017 · regional WWTP • ADWF: 3.3 mgd • PWWF: 14 mgd . A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA ... •](https://reader036.vdocuments.us/reader036/viewer/2022071008/5fc611d279ca866bca5fd214/html5/thumbnails/33.jpg)
A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA
Construction materials
• Integrated manhole systems
• Pipeline materials
• Trench materials
![Page 34: A Gravity Situation Eastside Trunk Sewer · 5/5/2017 · regional WWTP • ADWF: 3.3 mgd • PWWF: 14 mgd . A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA ... •](https://reader036.vdocuments.us/reader036/viewer/2022071008/5fc611d279ca866bca5fd214/html5/thumbnails/34.jpg)
A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA
Integrated manhole systems
• Water-tight design
• Improved quality control with factory fabrication
• Increased construction efficiency
• Reduced manhole diameter
![Page 35: A Gravity Situation Eastside Trunk Sewer · 5/5/2017 · regional WWTP • ADWF: 3.3 mgd • PWWF: 14 mgd . A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA ... •](https://reader036.vdocuments.us/reader036/viewer/2022071008/5fc611d279ca866bca5fd214/html5/thumbnails/35.jpg)
Construction
![Page 36: A Gravity Situation Eastside Trunk Sewer · 5/5/2017 · regional WWTP • ADWF: 3.3 mgd • PWWF: 14 mgd . A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA ... •](https://reader036.vdocuments.us/reader036/viewer/2022071008/5fc611d279ca866bca5fd214/html5/thumbnails/36.jpg)
A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA
Integrated manhole systems
Phase 1 (2007) Manhole Base
• Precast with HDPE liner, polymer concrete coating, and “boot”
connection
![Page 37: A Gravity Situation Eastside Trunk Sewer · 5/5/2017 · regional WWTP • ADWF: 3.3 mgd • PWWF: 14 mgd . A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA ... •](https://reader036.vdocuments.us/reader036/viewer/2022071008/5fc611d279ca866bca5fd214/html5/thumbnails/37.jpg)
A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA
Phases 2 and 3 (2013) Manhole Base
• Precast with fiberglass insert and gasketed connection
Integrated manhole systems
![Page 38: A Gravity Situation Eastside Trunk Sewer · 5/5/2017 · regional WWTP • ADWF: 3.3 mgd • PWWF: 14 mgd . A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA ... •](https://reader036.vdocuments.us/reader036/viewer/2022071008/5fc611d279ca866bca5fd214/html5/thumbnails/38.jpg)
A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA
Integrated manhole systems
Phases 2 and 3 (2013) Manhole Base
• Gasketed pipe connections
![Page 39: A Gravity Situation Eastside Trunk Sewer · 5/5/2017 · regional WWTP • ADWF: 3.3 mgd • PWWF: 14 mgd . A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA ... •](https://reader036.vdocuments.us/reader036/viewer/2022071008/5fc611d279ca866bca5fd214/html5/thumbnails/39.jpg)
A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA
Integrated manhole systems
Wall Liner
• Phases 1 and 2 – GSE StudLiner
• Phase 3 – Agru Sure-Grip Liner
![Page 40: A Gravity Situation Eastside Trunk Sewer · 5/5/2017 · regional WWTP • ADWF: 3.3 mgd • PWWF: 14 mgd . A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA ... •](https://reader036.vdocuments.us/reader036/viewer/2022071008/5fc611d279ca866bca5fd214/html5/thumbnails/40.jpg)
A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA
Integrated manhole systems
Wall Liner
• Welded liner joints, including HDPE to fiberglass
![Page 41: A Gravity Situation Eastside Trunk Sewer · 5/5/2017 · regional WWTP • ADWF: 3.3 mgd • PWWF: 14 mgd . A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA ... •](https://reader036.vdocuments.us/reader036/viewer/2022071008/5fc611d279ca866bca5fd214/html5/thumbnails/41.jpg)
A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA
Integrated manhole systems
Manhole Chimney
• Phases 1 and 2 – HDPE, wrap
• Phase 3 – fiberglass collar
![Page 42: A Gravity Situation Eastside Trunk Sewer · 5/5/2017 · regional WWTP • ADWF: 3.3 mgd • PWWF: 14 mgd . A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA ... •](https://reader036.vdocuments.us/reader036/viewer/2022071008/5fc611d279ca866bca5fd214/html5/thumbnails/42.jpg)
A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA
Integrated manhole systems
Inside Lateral Drop Connections
• Welded joints
• Boot connection
![Page 43: A Gravity Situation Eastside Trunk Sewer · 5/5/2017 · regional WWTP • ADWF: 3.3 mgd • PWWF: 14 mgd . A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA ... •](https://reader036.vdocuments.us/reader036/viewer/2022071008/5fc611d279ca866bca5fd214/html5/thumbnails/43.jpg)
A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA
Pipeline materials
• Phase 1 – HDPE-lined Concrete, double gasket
• Phases 2 and 3 – AWWA C905 PVC
![Page 44: A Gravity Situation Eastside Trunk Sewer · 5/5/2017 · regional WWTP • ADWF: 3.3 mgd • PWWF: 14 mgd . A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA ... •](https://reader036.vdocuments.us/reader036/viewer/2022071008/5fc611d279ca866bca5fd214/html5/thumbnails/44.jpg)
A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA
Trench materials
• Controlled Low Strength Material (CLSM)
• Crushed rock bedding (3/4”)
![Page 45: A Gravity Situation Eastside Trunk Sewer · 5/5/2017 · regional WWTP • ADWF: 3.3 mgd • PWWF: 14 mgd . A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA ... •](https://reader036.vdocuments.us/reader036/viewer/2022071008/5fc611d279ca866bca5fd214/html5/thumbnails/45.jpg)
A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA
Construction techniques
• Positive utility verification (potholing)
• Dewatering, shoring, soil stabilization
• Controlled low strength material (CLSM)
• CCTV inspection – allowable “bellies”
• Manholes testing
![Page 46: A Gravity Situation Eastside Trunk Sewer · 5/5/2017 · regional WWTP • ADWF: 3.3 mgd • PWWF: 14 mgd . A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA ... •](https://reader036.vdocuments.us/reader036/viewer/2022071008/5fc611d279ca866bca5fd214/html5/thumbnails/46.jpg)
A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA
Positive utility verification
• Complete enough potholes to
identify alignment challenges
ahead of construction
• Coordinate with utility
companies
• Allow time for utility relocation
or modification
![Page 47: A Gravity Situation Eastside Trunk Sewer · 5/5/2017 · regional WWTP • ADWF: 3.3 mgd • PWWF: 14 mgd . A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA ... •](https://reader036.vdocuments.us/reader036/viewer/2022071008/5fc611d279ca866bca5fd214/html5/thumbnails/47.jpg)
A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA
Dewatering, shoring, soil stabilization
• Dewatering wells at 50 to 100 foot spacing
• Shoring with soil stabilization
![Page 48: A Gravity Situation Eastside Trunk Sewer · 5/5/2017 · regional WWTP • ADWF: 3.3 mgd • PWWF: 14 mgd . A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA ... •](https://reader036.vdocuments.us/reader036/viewer/2022071008/5fc611d279ca866bca5fd214/html5/thumbnails/48.jpg)
A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA
Manhole testing
• Manhole liner spark testing
• Manhole pressure testing
![Page 49: A Gravity Situation Eastside Trunk Sewer · 5/5/2017 · regional WWTP • ADWF: 3.3 mgd • PWWF: 14 mgd . A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA ... •](https://reader036.vdocuments.us/reader036/viewer/2022071008/5fc611d279ca866bca5fd214/html5/thumbnails/49.jpg)
A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA
Pipe testing
• Joint Testing: vacuum, air testing
• Video: bellies
![Page 50: A Gravity Situation Eastside Trunk Sewer · 5/5/2017 · regional WWTP • ADWF: 3.3 mgd • PWWF: 14 mgd . A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA ... •](https://reader036.vdocuments.us/reader036/viewer/2022071008/5fc611d279ca866bca5fd214/html5/thumbnails/50.jpg)
Conclusions and What’s Next
![Page 51: A Gravity Situation Eastside Trunk Sewer · 5/5/2017 · regional WWTP • ADWF: 3.3 mgd • PWWF: 14 mgd . A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA ... •](https://reader036.vdocuments.us/reader036/viewer/2022071008/5fc611d279ca866bca5fd214/html5/thumbnails/51.jpg)
A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA
Conclusions
• Determine if system rehabilitation or conveyance is appropriate
• Evaluate life cycle costs for alternatives
• Evaluate available materials and techniques during project planning
• Learning curve for contractors
• I/I rehabilitation program could take 10 to 20 years to show tangible
benefits
![Page 52: A Gravity Situation Eastside Trunk Sewer · 5/5/2017 · regional WWTP • ADWF: 3.3 mgd • PWWF: 14 mgd . A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA ... •](https://reader036.vdocuments.us/reader036/viewer/2022071008/5fc611d279ca866bca5fd214/html5/thumbnails/52.jpg)
A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA
What’s next?
• Planning and assessment
• I/I rehabilitation
• Construction materials:
– Integrated manhole systems
– Pipelines: HDPE, plastic, fiberglass
– Trenches: CLSM
• Construction techniques
• Laterals
![Page 53: A Gravity Situation Eastside Trunk Sewer · 5/5/2017 · regional WWTP • ADWF: 3.3 mgd • PWWF: 14 mgd . A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA ... •](https://reader036.vdocuments.us/reader036/viewer/2022071008/5fc611d279ca866bca5fd214/html5/thumbnails/53.jpg)
A Gravity Situation – Eastside Trunk Sewer, Rohnert Park, CA
www.ghd.com