Construction Overview

CIPP Installation

This December and January, the sanitary sewer throughout the Interlachen neighborhood will receive maintenance and restoration to keep it operating safely and efficiently.

Work will start the first week of December and continue for six to eight weeks. Crews and equipment will be in the area, including roadways and sewer easements across private property, Mondays through Fridays and possibly some Saturdays, from as early as 7:30 a.m. to 6 p.m.

The sewer will still function during most of the work, thanks to bypass pumping. The area won’t be disrupted with open trenches, thanks to cured-in-place pipe technology.

You’ll need to restrict your use of the sewer for one day during construction. Read on for details. Noise, dust and odor are possible during the work.

What (and when) is restricted sewer use?

A typical sewer lateral

Your home’s sewer pipe, called a “lateral,” connects to a main sewer line. For one day during construction, your lateral will be plugged while crews work on the main line. You’ll need to restrict sewer use during construction hours to avoid backup into your home. Restricting your sewer use means don’t:

• Take a shower.
• Drain a bathtub.
• Run a washing machine or dishwasher.
• Flush toilets

If you anticipate particular difficulties in curtailing toilet use, please contact Kelly Uhacz, City of Fairview Public Works, at 503-674-6222 to discuss your particular situation.   

The date your lateral sewer line will be plugged depends on your location as work progresses. The contractor, Iron Horse, will leave a notice with contact information on your front door at least two days before your restricted-use day. Someone with Iron Horse will also knock on your door when you are free to resume full sewer use.

What about driveways, school buses and garbage trucks?

In general, the work won’t block driveways. If the contractor does need to use someone's driveway, it will coordinate with that homeowner in advance.

The contractor will also coordinate construction to minimize disruption to school bus routes and garbage pickup.

What is "cured-in-place pipe" (CIPP) technology?

Bypass Pumps with Diesel Generator in background

Cured-in-Place Pipe (CIPP) technology involves inserting a resin-impregnated tube into an existing pipe, expanding the tube against the pipe, and curing or hardening the resin using ultraviolet (UV) light, hot water, or steam under pressure. The result is a jointless, fully structural pipe tightly fit against the existing pipe.

CIPP technology has been used in North America for almost 40 years to structurally renew and extend the life of buried pipelines without costly and intrusive excavation.

UV-cured CIPP is inserted by "pull-in," which means pulling a resin-impregnated tube through the existing pipe:

• Before installation, a plastic pre-liner sheet is pulled into place and lubricated so the resin-impregnated tube can glide easily through the existing pipe.
• The tube is then inflated and pressurized against the host pipe, allowing the UV light train, equipped with an inspection camera, to inspect the tube for defects.
• After the inflated tube is inspected, the UV light bulbs are turned on and the pipe is cured.

UV-cured CIPP installation typically requires five major pieces of equipment:

• A closed-circuit television (CCTV) truck for inspecting the pipe before and after installation.
• A truck and trailer for transporting the uncured tube.
• A combination vacuum and hydro-jetting truck to clean the line of debris and other obstructions.
• A winch to pull the pre-liner and tube through the existing pipe.
• A truck to monitor and control UV curing.

Each piece of equipment is needed at separate times. For example, once the pre-installation television inspection is completed, the CCTV truck is moved away and the next truck brings the liner over the manhole.

How does bypass pumping work?

Bypass pumping continues sanitary sewer service during construction. It occurs continuously during CIPP installation and post-installation video inspection.

Bypass pumping for this project will be specified for reliability:

• A standby backup pump will be required at all times.
• The bypass discharge pipe will generally be high-density polyethylene (HDPE) with quick-connect couplings, or lay-flat hoses for low-flow mainlines.
• The bypass discharge pipe will be routed in the roadway between manholes and along the lake shoreline as required for each section of sewer lining.

What’s a sewer “lateral”?

It’s a private sewer pipe from your home to the public sewer main. Its name comes from generally running in a sideways direction compared to the sewer main.

As shown in the diagram, laterals have both upper and lower parts. The upper lateral runs from the home or business to a cleanout at the sidewalk or sometimes the property line. The lower lateral runs from the cleanout to the sewer main. If no cleanout is in place, the lateral is usually not considered to have separate upper and lower parts.

Laterals are the responsibility of the property owner. The Interlachen Sewer project will address mainline sewer rehabilitation only.

What’s a sewer "easement"?

It’s an area where a city or other agency has the right to enter, maintain, repair, inspect, improve, renovate and replace things such as sewer pipes and manholes; and to keep clear access to that area.

Easements on this project are in off-street areas.

Easements limit some rights of landowners. For example, the sewer easements along the Fairview Lake north shore, grants the City of Fairview the right to enter properties to access sewer pipes along the shoreline.

How will disturbed areas be restored?

CIPP installation is trenchless, minimizing the need for excavation. If the ground is wet or soft during the work, crews will take measures to mitigate disturbance outside the roadway.

Pre-construction photos will document the conditions of surrounding properties. Crews will restore the area to the best possible conditions once construction is complete. Since the CIPP technology and bypass pumping work are staged above ground, restoration is anticipated to be relatively minor.

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