Health alert: If sewer pipes are being replaced in your area, you may want to schedule a vacation day

Signs of progress are good, especially new infrastructure in the areas around our homes and places of business.  A new blacktop on the road–yay!  A new, brighter traffic light–yay!  New cables for internet in rural communities-yay!  However, there are some methods and materials that are not progressively better for our health.  Frequently, sewer pipes are not replaced, but renewed with a resin liner that’s called Cured In Place Piping (CIPP), and the fumes from it are toxic. 

Sewage line replacement is a big deal.  If the pipes are truly replaced, heavy equipment must be brought in to break up the road or surface, excavate the pipe, and replace it.  The traffic and businesses around it are disrupted for a minimum of a week to months, depending on the length of line to be replaced.  There’s a new, less expensive and less disruptive method of renewing the pipes, however.  CIPP is like a “band-aid” for damaged sewer pipes, because it adds a liner to the internal part of the pipe.  It’s not as simple as “peel and stick” though, because the process has more steps to make sure the liner attaches well and cures for a long life.

Here are the steps for CIPP in Portland, OR (Cured-in-Place-Pipe Lining (CIPP))

1. Sewage pipe is surveyed and damaged sections are assessed and measured for this technique.

2. Roots and debris are cleaned from the pipe to be lined.

3. A sewer bypass system is set up, if necessary, to re-route wastewater to other nearby pipes during the pipe lining process.

4. Set up and run a vacuum truck, to keep the pipe free of debris and water during pipe lining process.

5. Insert resin-soaked liner into the sewer pipe from the surface through a maintenance hole.

6. Expose the liner to heat, hot water or ultraviolet light to cure, or harden, the liner inside the pipe.

7. Open and reinstate sewer service lateral connections that were covered by the pipe lining.

8. Remove the bypass system, if any.

9. Conduct quality control inspections. 

The guide also has suggestions for “Unpleasant Odors and How to Prevent Them”:

“During the pipe lining process, residents may smell an odor like plastic or glue. This will dissipate quickly once the process is complete. The odor is from chemicals in the liner resin. The amounts detected by an independent industrial hygienist are below health risk levels.”  It seems that the odors experienced by residents in other locations is more than “unpleasant”, considering the severity of symptoms on this Human and Environmental Incident List.

Here’s where the hazards of this process occur: during manufacturing, during the heating process of installation, and afterward.  The resins used in CIPP are toxic, one of which is styrene.  Purdue University researcher Andrew Welton led a team to understand the process and mitigate hazards.  In two studies, in the Journal of Environmental Health and Environmental Science and Technology Letters, they showed that workers, and even bystanders, including children, lack adequate protection.

In this video, a clip of a city spokesperson (at about 46 seconds into the video) denies that any of the process is hazardous to the public or the workers.  This is common because city and county government officials may not understand the risks themselves. 

These chemicals have made hundreds of people ill, forced building evacuations and even led to hospitalizations. Playgrounds, day care centers and schools in several states have been affected, including in Colorado, Connecticut, Massachusetts, Michigan, Pennsylvania, Washington and Wisconsin. (Common Method of Sewer Repair Poses Health Risks)

Here is a diagram of how the fumes from CIPP can affect residents of nearby buildings and spaces.  Besides escaping to open air via the sewer access holes, they can travel up the damaged sewer line into buildings, and enter via any foundation cracks or appliances that connect to the sewer like toilets, sinks, and drains.  Typically there is a “P-trap” type water seal in place on these drains, but if the water dried up from lack of use, or gas pressure is too strong, the gases can blow through the P-trap and into the building. 

Fumes generated during sewer line repair, on the right, can enter nearby homes, schools and other buildings. Illustration courtesy Andrew Whelton, as shown in article Common Method of Sewer Repair Poses Health Risks.

This photo of CIPP in progress shows white gases escaping from a sewer access hole, which most people assume to be only steam.  Some of it may be steam, but as much as 9% of the resin is also emitted into the air.  The resin safety data sheets do not disclose all of the chemicals, and some entirely new ones are created during heating. Some cause nausea, headaches and eye and nasal irritation. They can also lead to vomiting, breathing difficulties and other effects.  Styrene, the most frequently documented chemical, is acutely toxic, and “reasonably anticipated” to cause cancer, according to the National Research Council.

Instead of citing the process as safe and telling people not to worry, contractors and city officials need to research and plan on how to keep CIPP fumes away from the public.  Currently, the Purdue University research team advises the following:

Residents should:

• Close all windows and doors, fill plumbing traps with water and leave the building during pipe-curing operations, especially when children are in the building.

• Report unusual odors or illnesses to health officials or call 911. Seek medical advice from health officials, not the contractors or pipe owners. Evacuate buildings when fumes enter.

If your municipal area is planning sewer repairs using CIPP, it’s wise to ask if they are aware of the dangers to residents, and how they plan to protect them.  It seems like the “sell” of this repair technique is leaving out or skimming over well-documented safety concerns.

Photo by Andrew Welton, Common Method of Sewer Repair Poses Health Risks