Sunday, March 21, 2010

A challenging job...

The house is in it's nineties...and so...are it's pipes. We are expecting a large group for an extended stay. I was expecting there would be some unpleasant troubles, so I asked the local septic service tech to pay a visit with his fiber optic camera on a sewer snake. It's just like a colonoscopy for your house drain. :)

Just above the ceramic hose holder at the top of the photo below is a drain fitting called a "cleanout", which is a threaded cap which permits access to the drain line. Into the opened cleanout he inserted the camera and we watched on the video display a morbidly interesting voyage down to "the end of the line". Along the way we were able to identify several pertinent features, i.e. side-branches of drains coming in to the main, each type, segment and joint of pipe and their condition, incursions of root-masses, etc. At any point, we could stop the camera on it's cable and use another tool he brought that could locate a transmitter mounted on the camera thereby locating it's exact location from above ground and it's depth below grade. The whole process is captured on a narrated dvd now in our possession. Come on over, we'll pop some popcorn and watch a movie!

At the point marked by the slash mark in the dirt at the bottom of that photo is trouble waiting to happen(cue scary music). The camera revealed a root mass and a broken clay pipe. Up to that point the pipe had been cast can tell by the texture of the inside of the pipe.

Next to that big root is buried a cast iron cleanout fitting, followed by a transition to clay pipe for it's next 50 foot traversal under granite wall and stairs on the way to the tank some 100 feet on down the line.

The view from the other direction:

Clay pipe was laid in 2 foot segments with a bell hub at one end; the next piece nesting in the hub and packed around with oakum or some other sealant, the joint then oftentimes overlain with mortar cement. After many years the tiniest root hairs can work their way into the joint and then, once inside the pipe, will metastasize into a thick clump of tangly root fibers. The cypress root that is surfacing like a humpback whale in the photos above lay directly on top of our pipe, is thicker than both my thighs, and considerably denser. It had a curious affinity for our pipe, and had wheedled it's way into the vulnerable joint, and then crushed her in it's grip.

Cast iron seems to have come in 5 foot sections ninety years ago, about the weight one man can manage. Once I had it out of the way, I could get down in the trench myself with seemingly every tool I own or could rent and clawed away at the meanest, orneryest, hardest, stubbornest mass of rock, root, riprap, soil, clay and concrete I think I've ever encountered. Ax, pick, bar, chainsaw, roto-hammer, jackhammer, chisel, hatchet, cut-off saw, skilsaw, sawsall, and grinder...

Every now and then, I'd come up for air and let the dust settle...

The crux of the challenge was getting to the next unbroken segment of clay pipe to which a repair could be attached...which fragile pipe was encased in solid rock & mortar, requiring the utmost tenderness in removal of said rock and mortar the closer I got to the necessary 2 inches of undamaged pipe. The broken segment disappeared under the bottom stone step of a short flight of stairs coming down from the terrace, so it was necessary to cut throught the 6 inch thick stone and remove a section of the 4 foot wide tread...a beautiful piece of rock...

A certain amount of adjacent granite needed to be removed just to bring tools close enough to the pipe to work. As the last day of winter turned into evening, I approached the nub of pipe with a 1/4" rock chisel, a small hammer, and a grinder with a diamond-tipped cutting wheel. Just as I was gaining that first inch, I realized that half the circumference of that inch was cracked through in several places and ready to crumble apart. I carefully peeled off the pieces, which I could see had long been broken because the inner surfaces of the breaks were coated with moist soil, cleaned them with a small brass bristle brush and glued them together and back onto the body of pipe with superglue (cyanoacrylate). For my final step of the day, I wrapped the inside of the pipe with fiberglass mesh tape and slathered it all with a layer of clear epoxy, inside and out.

On the first day of Spring, I was able to continue removing rock and mortar, successfully managing to acquire enough intact pipe to affix repairs to. The epoxy patch had held perfectly. The final stages were the most difficult, due to space and access constraints in the trench, noxious tool noise and dust, and the tenacity of mortar on friable clay pipe. At that point I was simply agog at the whole process, and not the least that it was accomplished so narrowly. Alternatives I won't bother to describe had been playing out in my mind for the previous 12 hours.

The way was now clear to make the repair: the trench was cleaned, the new pipe brought in and cut to size, the repair fittings prepared and all was assembled in a matter of moments:

Below you can see the section of stair tread removed which will be replaced with new grout:

Rock salt is placed around the new repair to discourage roots from seeking out any entry to the pipe.

So, remember: a straight flush always beats a full house!


Sarah Beth said...

I can't believe you have the energy to blog bout it after all that!

Mark said...

I needed to talk....PTSD an' all.