Get to the Root of Sewer Problems

From the day the dirt is tamped into place, a wastewater system faces inevitable destruction by the forces of nature and the abuses of man. Soil settles and shifts, straining pipes and joints. Water invades tiny pores and then freezes, opening cracks. Rats have been reported to gnaw through concrete.

Preventive maintenance can extend the longevity of wastewater treatment systems. Adhering to a schedule for pipe treatment and inspection can save a city many thousands or even millions of dollars. An annual herbicide flush will fend off invading roots, and healthy colonies of fat-eating micros can stop blockages before they start.

Because blockages are costly to cities and frustrating for citizens, it is worth understanding what causes blockages and how to prevent them.

Fat City

Even new sewer mains are susceptible to blockage by fats, oil, and grease (FOG) that residents and businesses pour down the drain. FOG accounts for 25% to 50% of the organic matter in wastewater and can block an 8-inch pipe in less than a month.

FOG can overload treatment plants, accumulating in clarifiers and digesters, contaminating effluent, and requiring costly repairs and maintenance.

Mechanical FOG control uses high-pressure jetting equipment and a vacuum truck to blast the fatty obstruction to pieces, restoring flow quickly but releasing a tide of organic material that may strain water treatment facilities.

Chemical FOG control uses caustics, surfactants, or enzymes to break up a blockage and wash it downstream. Some chemicals can even break down the fats and oils before they reach the treatment plant.

Biological control measures use live microbes to digest FOG slowly as it accumulates in the pipes, avoiding blockages all together. Microbes attach to the pipeline walls, forming colonies that prevent buildup. Biological treatments are ideal when the flow is slow, but not yet completely blocked. They work slowly, with no caustics, solvents, or detergents, making them an environmentally friendly solution.

From FOG to FROG

For aging wastewater systems, the most invasive agent of destruction is not FOG, subsidence, ice, or rats. Trees are the culprits invading drains and clogging sewers.

So add an 'R' for 'roots' to the acronym FOG. FROG, fats, roots, oil, and grease, conspires against open and flowing pipes.

When roots invade pipes, one quick way to restore flow is to clear pipes with a root cutter. But even the best cutters leave tenacious roots, making cutting a temporary fix at best. Repeated cutting and tearing of roots from the pipe walls can further damage pipes and require them to be replaced.