If you happened to ride down my street in Lower Mills one day last month, you might have noticed the construction crew that had set-up in front of my driveway. It was a contractor and they were there because we were dealing with a failure of the main drain from the house to the street.

It turns out the old drain pipe, like many in the neighborhood, was made of clay and after years of reliable service it had begun to fail. These clay pipes sit deep in the dirt, six feet and more below ground, and over time they had developed little fissures. Unlike modern-day metal and fiberglass, the solid clay pipes can be breached by the roots of nearby trees, and over time the clay had begun to rupture. Five years ago, when we first dealt with a similar problem, the break was located on our property. Then a drain excavator company came and dug up the driveway, and replaced a ten-foot length of breached clay- at a cost of $6,000.

Last month, the main drain showed problems again, and our plumber used video equipment that allowed an interior view of the pipe. This time, the breach was beyond our property line, underneath the sidewalk and street.

The urban legend is that pipes beyond the property line are the responsibility of the city, but as we learned last month, that's wrong. Turns out, the property owner is responsible for maintenance drain pipes all the way to the main drain in the street.

We learned that by contacting the Boston Water and Sewer Commission (BWSC) for help in making the repairs. A BWSC inspector arrived promptly to see what our contractor saw and an agency brochure gave this explanation:

"A sewer lateral, also known as a building's sewer or storm drain, is the waste disposal pipe connecting a home or business to the BWSC's main sewer or drain line in the street. While the BWSC is responsible for maintaining its sewer and drain lines located in the public way, property owners are responsible for the maintenance of their building's entire lateral from inside the property's basement to BWSC's sewer or drain lines in the street."

The repair was all on us, we sadly learned.

But the agency inspector brought some good news, in the form of a BWSC grant, in an amount up to $3,000, that would help cover the cost of the excavation and repair under the "public way," the street and sidewalk.

To be eligible, property owners must obtain three repair estimates from a list of about 50 approved contractors, and file them in advance at the BWSC offices on Harrison Avenue.

The one-time grant is available for all eligible owners and it provides a surprising but very welcome measure of relief from the high cost of the dig.

On a personal note, it should be said that dealing with the BWSC was a very uncomplicated process and the inspector and employees we encountered were unfailingly courteous and very helpful. Moreover, the Fields Corner contractor, Walsh Corporation, 77 Park St., just returned last week to make a permanent repair to the patched sidewalk. I would recommend them without hesitation.

Here's some advice for anyone facing a similar drain problem: know the name of a plumber willing to respond quickly, and also keep handy this BWSC phone number: 617-989-7000.

- Ed Forry

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