Water Pipeline Rehabilitation Project - Commercial Avenue

What is Cured-in-Place Pipe (CIPP)? 

Madison was the first city in Wisconsin to rehabilitate aging water pipelines using Cured-In-Place Pipe (CIPP) relining methods. The process allows Madison Water Utility (MWU) to create a new pipe inside the old, deteriorating water pipeline without digging up the street for a full replacement, saving both time and money. 

This water pipeline rehabilitation project will use the CIPP lining technology, a process where a woven fabric tube is saturated with a liquid epoxy resin, pulled through the inside of the deteriorated pipe, and then inflated and cured with hot water or steam to form a new plastic pipe inside the old pipe. The rehabilitated pipes have full structural strength (more than simply a coating or lining inside the old pipe) and are expected to last at least 50 years before additional maintenance needs to be considered.

This will be Madison Water Utility’s tenth year doing water pipeline rehabilitation contracts in this manner.  We have been working with and receiving assistance from WI Department of Natural Resources (DNR) over the years to develop, evaluate, and refine successful specifications for this technology. 

Construction is proposed to begin in June and be completed by August at an estimated bid cost of $797,080.

Image credit: Madison Water Utility

Commercial Ave CIPP Project Overview

Madison Water Utility is committed to delivering innovative and environmentally-friendly solutions to improve water service, water quality and fire protection throughout our system. This requires continual investment in our distribution system. In the coming months, one of these distribution system improvements is proposed to take place in your neighborhood and we want to provide you with some information regarding the proposed project. 

MWU will be rehabilitating existing water mains on the following street segments:

• Ziegler Road (Commercial Avenue Service Road to Nakoosa Trail)
• Redland Drive (Commercial Avenue Service Road to Nakoosa Trail)
• Bewick Drive (Commercial Avenue Service Road to Nakoosa Trail)
• Pulley Drive (Commercial Avenue Service Road to Nakoosa Trail)

In order to ensure a safe and efficient working environment, street parking within these areas will be prohibited during the project, and there will be short-term, off-peak closures to through traffic.

These street segments were selected primarily because of their history of water main breaks. The CIPP process allows a new pipe to be constructed inside of the existing deteriorated pipe, with minimal excavation in the street. The structural liner is designed to meet the physical strength properties of a new pipe. The contractor that is awarded the contract for this work will be working on-site along with Madison Water Utility crews.

During construction, the existing water main must be taken out of service. Affected customers will be provided water service through an above-ground, temporary drinking water system. The temporary system is disinfected, sampled and tested using the same procedures as all City of Madison water pipe installations. Driveway and roadway crossings of the bypass system will be ramped or buried to maintain vehicular access and traffic flow during construction. 

While being served on the bypass system, affected properties could have their existing water meter removed and then reinstalled once the rehabilitation is complete. 

Water Supply and Water Quality Benefits

Use of CIPP technology in the MWU water system meets the National Sanitation Foundation (NSF) Standard 61 for drinking water health and safety. This certification is required by the DNR to ensure water meets all standards set by the Environmental Protection Agency (EPA) Safe Drinking Water Act.

Renewing this pipeline using CIPP will minimize breaks and improve both water quality and flow in the area at a reduced cost to the ratepayer. 

Frequently Asked Questions (FAQs)

Why not install new water mains instead of rehabilitating the existing ones?

CIPP has recently become the most cost effective option for rehabilitating water mains, when compared to traditional open trench construction. This technology also lessens the impact on residents, by reducing excavation and overall construction duration. CIPP becomes a viable alternative in other cases such as socially or environmentally sensitive areas, and time critical situations.

Is CIPP as good as traditional pipe replacement materials?

The structural CIPP pipe meets the WI-DNR’s physical requirements for new pipes. The CIPP design calculations are prepared by a Professional Engineer and submitted to WI-DNR for review and approval prior to beginning construction. The CIPP liner pipe is designed to withstand at least a constant working pressure of 100-psi for at least 50-years, with a factor of safety of 2.5. The calculations are to assume the CIPP liner as a stand-alone pipe, not relying on any remaining integrity of the deteriorated “host pipe”.

What is involved in CIPP process?

The CIPP pipe itself consists of two polyester layers and a durable water-tight surface layer. The polyester tubes are filled with a liquid epoxy resin. The resin-saturated tube is installed inside the existing water main between two small excavations at each end of the pipe segment. The tube is pressurized to form tightly against the existing pipe-walls and heat is applied to solidify the resin as a new continuous pipe.

After the pipe is installed, service connections are reinstated from within the pipeline using a small robotic drilling system. The CIPP project will be subjected to the same water pressure and water quality testing requirements as any other new water main.

Are CIPP systems safe for drinking water?

All CIPP systems for use in drinking water systems must be certified by the National Sanitation Foundation (NSF) “Standard 61: Drinking Water System Components – Health Effects”, which is the standard required by the Wisconsin Department of Natural Resources. The NSF 61 standard tests for the presence of regulated substances set by the Environmental Protection Agency (EPA) Safe Drinking Water Act, and to be certified no substance may exceed 10% of the EPA’s maximum contaminant level.

Will I still have water service during construction?

Before construction begins, customers will be provided constant water service through a temporary, above-ground water main. The temporary main will be constructed entirely from NSF 61 drinking water components and it will be disinfected and tested prior to providing service. The temporary main is connected to the house at an exterior hose bib. Existing water meters may need to be removed while connected to the bypass system.

What can I expect during construction?

Construction activities will begin in June and are scheduled to finish in August. The contractor may work between the hours of 7:00 AM and 7:00 PM, Monday through Saturday and 10:00 AM and 7:00 PM Sunday. Roads will be open with some through traffic restrictions, however there will be several small excavations that will be fenced and well-marked. Temporary main will be ramped where it crosses traffic or driveways. Madison Metro Bus services will not be impacted. Street parking will be eliminated during the project.