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Triton Lining Systems LLC. The City of Sac City, Sac City Iowa, Water Distribution Pipe In-Situ Rehabilitation July 2012. Project Details. 1,129’ x 6” cast iron water main 1,563’ x 4” cast iron water main Installed – 1940’s, 1970’s, 1990’s Properties affected – 41 homes, 105 residents
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Triton Lining Systems LLC. The City of Sac City, Sac City Iowa, Water Distribution Pipe In-Situ Rehabilitation July 2012
Project Details 1,129’ x 6” cast iron water main 1,563’ x 4” cast iron water main Installed – 1940’s, 1970’s, 1990’s Properties affected – 41 homes, 105 residents Subdivision - Oak Hill Drive Problem – Severe discolored water complaints
The Problem / Cause The conveyed water interacted with the cast iron, causing severe tuberculation build up, internal corrosion, loss of hydraulic efficiency, loss of carrying capacity, degradation of water quality & pipe integrity
Attempted Remedies The system was ‘looped’ – the problem got worse Super chlorination of the entire water system (break point chlorination) for 30 days - helped short term but the problem returned Hydrant flushing increased – occasionally made the problem worse Direction of water flow changed – no effect Supplied customers in the effected area with water filters - helped but didn’t fix the problem
The Search for a Solution Contacted Iowa Rural Water Association Contacted American Water Works Association Talked with vendors All resources had no new ideas other than replacing the mains Started searching the internet for ideas
Potential Solutions 1. Temporary fix: Furnish the homes with a high end filtration system - Cost approx. $1,000.00/home ($41,000 total). Filters will last 10-15 years with cleaning annually but does not fix the problem 2. Semi-permanent: Pig or swab the lines - this would not fix the problem just delay it’s return. Associated issues - plugged service lines, plugged water heaters, residue in the pipes. Cost - $12,925.00 3. Long term/semi-permanent fix: Rehabilitate the pipe in place - a longer lasting solution (50 year design life), medium cost but permanent elimination of problem 4. Permanent Solution: Replace the main – high cost
Narrowing the Options Main Replacement Pro’s - Permanent Fix - City Crews familiar with process Con’s - 2 year duration - Cost - Cost - Cost Main Rehabilitation Pro’s - Less Cost - Speed of installation • - No Engineering fees • - Less social disruption Con’s - Unfamiliar to City crews • - 1st in the State of Iowa to use this technology
The Chosen Solution City personnel searched for an appropriate technology that would deal with the problems, while offering a long term, cost effective solution They found and employed Triton Lining Systems to rehabilitate the piping system and eliminate all the problems associated with it
Planning The City & Triton met to discuss the project The project area was walked, all excavation locations identified & marked, temporary water system mapped out, proposed working sequence planned, responsibilities determined & the final price agreed
Working Partners a Novel Approach The City & Triton formed an excellent working relationship where City personnel were utilized to undertake the functions of the project they were equipped for and accustomed to doing, while Triton performed the actual cleaning & lining of the pipes This scenario enabled the project to be complete in approx. 16 weeks with minimal social disruption and at a saving of over $1,575,000 compared to traditional remove and replace
The Rehabilitation 9 Step Process • Pipe Location / Access – City Personnel • Bypass – City Personnel • Excavation – City Personnel • 4. Isolation – City Personnel • Cleaning – Triton • Inspection (Pre lining) – Triton • Lining – Triton • Inspection (Post lining) – Triton • Re Connection / Disinfection – City Personnel
Pipe Location / Access Excavation locations were pre determined by Triton, utility locates were organized and performed by the City Road cut permits were obtained prior to construction
Bypass An above ground bypass system was installed to feed water to all properties affected by the construction This meant customers were only affected for a very short time during the set up and removal of the bypass system
Excavation Wherever possible, excavations / access openings were made at existing fittings (valves, tees, fire hydrants, bends etc.) This enabled the opportunity to upgrade the entire system
Isolation valves that only affected the pipes within the project area were identified Valves were checked for operation and complete shut down prior to construction Isolation
Pipe Cleaning Pipe scrapers were pulled through the line several times to loosen any tuberculation and buildup, this was done with the additional use of water
Plunging / Swabbing After scraping, plungers were pulled through the line several times to remove the loose debris and any remaining liquids Foam swabs were then washed through with water to remove any remaining debris
Swabbing Finally, foam swabs were blown through the pipe with compressed air to remove fine particles and dry the pipe
CCTV Inspection The cleaned pipe was then cctv inspected for verification and effectiveness of the cleaning
Inspection (Pre Lining) The purpose of the pre lining inspection is verify the effectiveness of the cleaning and identify any potential problems such as: Un clean pipe Un known valves Bends Standing or running water (leaking services) Over poured lead joints (lead fish) Repair sections / open joints / clamps Low service connections Obstructions
Control Systems Computerized metering and monitoring ensure quality and repeatability of applied linings A hard copy print out records all pertinent information and allows for verification of lining parameters
The Pipe After Lining The rehabilitated pipe will never suffer from any of the problems it had prior to the process The lining has an AWWARf design life of over 50 years
Lined Pipe(Showing service connection) The Triton In-Situ spray lining process doesn’t block service connections
Post Lining Inspection The cured lining was inspected via CCTV to ensure lining quality
Re Connection The City then reconnected all pipe work and checked the couplings under pressure
Disinfection Following the pressure testing of the new pipe and fittings the City disinfected / chlorinated the pipes in accordance with local and AWWA standards Once the bacteriological samples had passed they reconnected the properties back to the main, removed the bypass, back filled the excavations and reinstated the surface
Results Upon completion of the project fire flows were restored, the pipe has long term corrosion protection, chlorine residual is maintained, discoloured water complaints ceased, the problems will never return and customers are happy Additional benefit - saving $1,575,000.00
Project Responsibilities Summary City Personnel Utility locates Bypass installation Excavation Pipe removal Pipe reconnection Backfill Surface reinstatement Bypass removal Triton Pipe cleaning Post cleaning cctv inspection Pipe spray lining Post lining cctv inspection (City personnel gave assistance to Triton with the above)
Triton Lining Systems LLC.PO Box 1476 Carefree, AZ. 85377Tel: 407 928 9339The City of Sac City302 East Main Street, PO Box 37Sac City, Iowa 50583Tel: 712 662 7593