Public Information for Smoke Testing Program

The City has completed all planned smoke testing for 2011.
The smoke testing program will resume in April 2012

Quick Jump Links

Public Notification
Public Preparation
FAQs
Study Area Schedule
MSDS

The City of Newport is currently in the process of negotiating a Combined Sewer Overflow (CSO) Corrective Action Plan (CAP) with the Environmental Protection Agency (EPA) that will direct the CSO Program for the next 8+ years. A CAP is a schedule of CSO control activities that is negotiated with EPA as part of a consent agreement.

The purpose of the CSO control activities is to identify and remove sources of stormwater flow from the collection system in an effort to reduce the number of CSOs. Although the CAP is no finalized, the City has been proactively addressing items from the draft CAP.

As part of proactively addressing items from the draft CAP, the City of Newport is implementing a smoke testing program as part of an overall conveyance assessment. Smoke testing is an effective way to locate and identify problems and defects in the collection system that can contribute to CSOs and decrease the existing capacity and efficiency of the collection system infrastructure.

The engineering firm CH2M HILL is currently working with the City of Newport to implement the smoke testing program.

Public Notification

Public door hanger notification for smoke testing of sanitary sewer lines in the City's study area will be distributed to residents and commercial areas approximately 24-72 hours prior to field investigations.

The door hanger will describe the pending smoke testing efforts and what should be done in advance to minimize smoke from entering buildings. Residents do not need to be home during the testing. Contact information will be provided on the door hanger in the event smoke does enter a building.

Neighborhoods to be tested will be published monthly on this project website at the Study Area Schedule link. Residents are encouraged to use the links on this site to learn more about smoke testing.

During testing, crews will seal off segments of the sanitary sewer and push smoke into the sewer pipelines with smoke blowers. Materials used to generate the smoke are non-toxic, harmless, virtually odorless, and do not create a fire hazard.

Should smoke enter your home, the room should be promptly ventilated through an open window or door. Visit our Public Preparation link for additional information.

General goals of a conveyance assessment program are to find and reduce defects in the wastewater collection system, help control wet-weather flows, eliminate future wastewater overflows and backups, and aid in infrastructure improvement and rehabilitation.

Eliminating wet-weather induced problems helps reduce costs of excessive relief sewer construction and protects the health and well being of the public and the environment.

Public Preparation for Smoke Testing

The smoke that you may notice rising from the vent stacks on house roofs or from holes in the ground is: NON-TOXIC, HARMLESS, VIRTUALLY ODORLESS, AND CREATES NO FIRE HAZARD.

Smoke should not enter into buildings unless leaks or plumbing defects exist. However infrequently used drains may permit smoke to enter. Please make sure that the elbow traps for seldom-used drains, sink traps and other plumbing fixtures have water in them by pouring approximately 24 oz of water into each drain.

This will add moisture to drains that are not often used. Drains can be prepared as soon as notification has been issued for smoke testing in the area. Preparation procedures only need to be performed once before smoke testing in the area begins. Residents do not need to be at home during smoke testing.

Note that it is possible that smoke could also enter your building around a faulty wax ring seal at the base of toilets. Should smoke enter a building there is a chance that the smoke will set off an active smoke alarm. The room should be ventilated through an open window or door.

Acute exposure can cause irritation of the respiratory system. Occupants are urged not to accept exposures that could cause irritation. Leave the area and ventilate well to dissipate the smoke. Use the contact information included on the Smoke Testing door hanger to notify the condition assessment technicians who are conducting the smoke testing.

FAQs

• What is the purpose of Smoke Testing?
• What is a Smoke Test?
• Is the smoke hazardous?
• Will I have smoke coming into my house?
• I see smoke coming up in my yard!
• I don't see any smoke at all!
• Is anyone going to call on me?
• Should I do anything to prepare?
• Manufacturer's MSDS: PDF Download

FAQsWhat is the purpose of Smoke Testing?

A wastewater conveyance system or sanitary sewer system is designed to transport wastewater to a treatment facility. In dry weather it usually does so without issue. However, in wet weather, storm-related runoff may leak into the sewer system, resulting in an increased volume of flow the system wasn't designed to handle.

This situation is called rainfall derived inflow and infiltration (RDII or I/I). RDII is the process of storm water runoff getting into the sanitary sewer system.

Storm water entering into the sewer system from a manhole, at left, and from a defect inside a pipe, at right.

RDII such as depicted here can result in an overburdening of the sanitary sewer system, which may result in Combined Sewer Overflows (CSOs).

Not only do cracks, leaks, and defects in the sanitary sewer line allow RDII to enter, but blockages and maintenance problems within the pipes can also hamper the flow. These blockages could be attributed to vegetation roots, offset pipe joints, and even broken or collapsed pipe.

Although above ground problems, such as CSOs, are indicative of an existing problem somewhere within the sewer pipes, locating that problem can be challenging. A smoke test is one of the best ways to locate and mark breaks and defects in a sewer line. This is why many cities and municipalities implement smoke testing programs as a cost-effective method to assess the condition of conveyance systems.

Much of our nation's infrastructure is aging and deteriorating rapidly. In older parts of some cities, entire segments of sewer networks have been around for decades--some even date from the turn of the century or earlier.

What is a Smoke Test?

High-capacity blowers are used to pump smoke into a manhole (left photo). In the right photo, smoke is pushed into the system and emerges from cracks in the sidewalk and at a downstream manhole.

A smoke test is the process of injecting artificially produced smoke into a blocked off pipeline segment to see where the smoke emerges. If the sewer is in good condition then the forced smoke will emerge at the other end of the line. However, if the line has defects, the smoke will find the break and try to escape through the break.

It is not unusual to see plumes of smoke issuing up from peculiar places, such as cracks in the street, or in residential yards during smoke testing.

A three or four person crew will conduct the tests. Each crew member will have proper identification and use well marked vehicles. The test is performed by injecting opaque-colored smoke into an isolated sewer with specially designed blowers.

Traffic concerns are controlled and separate blowers are placed over the upstream and downstream manholes of the line to be tested.

While the smoke is being injected into the sewers, crews fan out around the smoke test area to observe and flag the places smoke escapes. Technicians document the locations of defects with digital photos and diagrams so defects can be analyzed later and repaired.

Is The Smoke Hazardous?

The smoke utilized during smoke testing is hydrated zinc chloride and is commonly used in the industry.

"Superior Smoke can be used without hazard if applied as directed. The main effects of the smoke are some minimal irritation of the throat and an awareness of an odd odor. These effects act as a warning and are desirable to prevent voluntary overexposure." Material Safety Data Sheet (MSDS)

While the smoke is not considered harmful, it is recommended to avoid prolonged periods of exposure. If smoke appears from a drain inside your residence, open windows and ventilate well to dissipate the smoke.

Will I have smoke coming into my house?

It is possible, although rare, that smoke could enter a residence through a drain trap which has dried out or some other plumbing defect such as an un-trapped washing machine drain.

Private properties may have several connections to the sanitary sewer system such as downspouts, floor drains and sump pumps. If these become clogged or blocked, they could cause problems.

Additionally, defects can allow toxic fumes and wastewater to seep up into the residence itself.

I see smoke in my front yard!

That may indicate a break or other defect in the sewer line.

In these photos, a defect in an underground sewer pipe is allowing smoke to escape up through the ground.

However, smoke doesn't always originate at the spot the smoke plume emerges.

Sometimes smoke will escape through a defect in the sanitary sewer line, then travel or migrate along the pipe until it finds a way to rise to the surface.

I don't see any smoke at all!

This may be good.

If the sanitary sewer line is in a state of good condition, the smoke will migrate along the sewer network and appear at a distant manhole or some other area where the Conveyance Assessment Technician expects to observe smoke, such as the sewer vent pipe on top of a residence. But in some cases, the smoke doesn't reappear at all.

Since it has to go somewhere, then a process of investigation and research begins to try and determine where the smoke is ending up.

Is anyone going to call on me?

A technician checks the drainage features of a private residence.

CH2M HILL staff may need to contact property owners to secure permission to inspect around the property.

Additionally, technicians may need to identify features of a building's drainage system such as downspouts, area drains, service laterals or sump pumps.

Conveyance Assessment Technicians carry appropriate identification and use clearly marked vehicles.

Should I do anything to prepare?

During smoke testing, field crews force opaque smoke into the sanitary sewer. The possibility exists for smoke to enter a residence via a defect in the sewer pipes or infrequently used drains.

A drain trap, the S-shaped curvature or elbow in the pipe typically found under sinks, exists to capture and hold water in the trap's curve.

This level of water in the trap creates a type of seal and blocks gasses from rising up through the drain and into the residence. A dry trap could be found in drains which are not used regularly and may allow smoke to enter the residence.

Study Area Schedule

There is currently no smoke testing being performed in the City

Please see the map for more detail on the area scheduled for smoke testing.

Material Safety Data Sheet (MSDS)

Download the latest version of Adobe Reader