Water Main Rehabilitation Cured-In-Place-Pipe Technology 4th Street Water Main Lining Project Jason Cook, PE, PMP

AGENDA General Construction Sequence Project Background Preliminary Engineering Final Design Efforts Construction Key Takeaways/ Lessons Learned

GENERAL CONSTRUCTION SEQUENCE Locate and verify pipe size Install temporary bypass system Excavate access pits Cut, clean, and inspect existing main Map and plug all service connections Wetout, install, and cure liner CCTV inspection of liner Hydrostatic testing

GENERAL CONSTRUCTION SEQUENCE Reinstate services Disinfect newly lined main Reconnect water distribution system Remove temporary bypass and restore site

PROJECT BACKGROUND Pilot Project for CFPUA Is CIPP a viable option? Can it mitigate typical construction impacts? When and where else should it be considered? CFPUA is familiar with CIPP of gravity sewers

PROJECT BACKGROUND Project Location 4th St. between Castle St. and Willard St. Established urban area of downtown Wilmington, NC. Encroachment on multiple right-of-ways: City of Wilmington NCDOT CSX Project Area

PROJECT BACKGROUND Numerous above/below ground utilities: Sanitary Sewer Stormwater Gas Telecom Power, etc. Historical site features: Brick Roadways Granite Curb Old Growth Trees, etc.

PROJECT BACKGROUND Water Main Characteristics 12” CI installed in mid-1960’s. Mostly straight alignment. Residential service and branch main connections. History of maintenance requirements.

PRELIMINARY ENGINEERING Is CIPP a viable option? Establish key design considerations Overall condition of the existing main? General alignment of the existing main? Number/location of valves, hydrants, fittings, etc? Working pressure of existing main? Semi-structural or fully structural liner per AWWA M28? Quantity and type of service connections?

PRELIMINARY ENGINEERING Tools and Available Resources As-built drawings GIS information Field survey Water system model Maintenance records Discussions with operations

PRELIMINARY ENGINEERING CIPP Product Requirements NSF 61 certification Class IV per AWWA M28 Exceed system operating pressures Future tapping

PRELIMINARY ENGINEERING Available CIPP Products AquaPipe by Sanexen RS Blueline by RS Technik NordiPipe by Sekisui InsituMain by Insituform

PRELIMINARY ENGINEERING Additional Preliminary Engineering Steps Cost Comparison between CIPP & Open Cut Manufacture estimates, past experience, etc. Isolation options & temporary water setup Permitting requirements

PRELIMINARY ENGINEERING

FINAL DESIGN EFFORTS Need a Clearer Picture SUE and Survey How far should we go? What has changed? Notable site characteristics: Location/depth of existing utilities Unique system connections Historical elements System isolation options

FINAL DESIGN EFFORTS Locate Access Pits What are system reconnection requirements? What are the maximum lining lengths? What impacts will result from access pits? Traffic control Existing utilities R/W encroachment

FINAL DESIGN EFFORTS

FINAL DESIGN EFFORTS Traffic Impacts

FINAL DESIGN EFFORTS Permits and Agency Approvals NCDOT NC DEQ Public Water Supply Erosion & Sediment Control City of Wilmington Engineering (right-of-way, streets cuts) Fire Department CSX

FINAL DESIGN EFFORTS Bidding and Award Approval Criteria Licensed/Certified Installer 40,000 LF of similar size in past 3 years Bid Structure and Range Base Bid, Alt #1 and Alt #2 $1.3M, $1.9M, and $5.1M

CONSTRUCTION Locate and verify pipe size Unlined Cast Iron Cement Lined Cast Iron

CONSTRUCTION 2. Install temporary bypass system

CONSTRUCTION 3. Excavate access pits

CONSTRUCTION 4. Cut, clean, and inspect existing main

CONSTRUCTION 5. Map and plug all service connections

CONSTRUCTION 6. Wetout, install, and cure liner

CONSTRUCTION 6. Wetout, install, and cure liner (cont.)

CONSTRUCTION 6. Wetout, install, and cure liner (cont.)

CONSTRUCTION 7. CCTV inspection of liner 8. Hydrostatic testing

CONSTRUCTION 9. Reinstate services

CONSTRUCTION 10. Disinfect newly lined main 11. Reconnect water distribution system

CONSTRUCTION 12. Remove temporary bypass and restore site

KEY TAKEAWAYS & LESSONS LEARNED Key Project Drivers Configuration of Distribution System Influence number pits required System isolation and temporary water requirements Location of Distribution System Permitting (R/W encroachments, city/state requirements) Paving and site restoration requirements Traffic impacts

KEY TAKEAWAYS & LESSONS LEARNED Key Project Drivers (cont.) Condition of Distribution System Semi-structural or fully-structural liner Existing valve operation Variation in system materials Operation of Distribution System System operating pressures CIPP liner thickness NSF 61 certification Future tapping of lined main

KEY TAKEAWAYS & LESSONS LEARNED Risk of cost variance Weather can change lining operation procedures Plan for temporary water impacts Testing of the installed liner is a must

QUESTIONS Jason Cook, PE, PMP Jeff Theberge, PE jcook@hazenandsawyer.com Jeff.Theberge@cfpua.org