October 18 , 1998
Times, Bad Times - Rubble Trench Part I
From the start, there would be good times and bad times. This last week was one of those bad times. It all started out very promising but as you will read, things ended the week on a bad note.
The goal this month was to get the rubble trench foundation dug before winter sets in. A rubble trench foundation is a foundation that was frequently used by Frank Lloyd Wright. Since we decided not to have a basement, it seemed silly to spend lots of money building a concrete frost wall to support the frame of our house. The idea is to build a house on a stable foundation that will not heave from frost. This can be accomplished by using 1.5" rock filled into a trench that has adequate drainage.
I took Friday off from work to meet Russ to dig the trench for the rubble foundation. Russ's job was to dig a 4' x 2' trench in a circle, 42' in diameter. I had already outlined the trench the week before to make the job easier. The trick was to get a small bucket for the back hoe. Russ came to the job site with a 20" bucket. This would end up creating a trench of at least 24" by the time all of the rock and clay were removed. Digging a circular trench is quite difficult. Back hoes are traditionally made to work straight lines. Russ would frequently have to shift the hoe to keep following the circle.
Russ started digging the trench and promptly hit into some pretty big boulders. We already knew that this might happen. When the hill was being excavated, there were some pretty good sized rocks not too far from the surface. Once you get down about 3' the rocks magically disappear and there's nothing but soft clay. Unfortunately, these large boulders made the sides bigger than 2', but there was no harm done. If the trench ended up being larger, it takes more gravel to fill the trench back, but it has no bearing on the stability beneath the footings.
Russ spent about 4 hours digging and got about two thirds done when the hydraulic hose busted on the back hoe. This was a bit of a bummer. Russ would have to get a custom hose made and it would take the rest of the day. We knew our time was limited. The forecast called for rain on Saturday and this could prevent us from finishing the job.
Saturday morning came with Russ right on schedule. He had the new hose and there was probably another six hours worth of digging to be done. The clouds were thick and ominous, but we pursued. Russ also needed to get the first load of rock to put into the base of the trench. Just before noon, Russ got most of the circle dug. I was busy cleaning out the rough edges to the trench. The wind started to pick up, it was getting colder and rain began to fall in earnest. It was decided that we would have to wait until next week to complete.
About 45 minutes after Russ left, the weather turned milder and the sun was peeking through the clouds. It was a pity that Russ had left. We could have gotten the drainage trench dug before the end of the day. My biggest concern at the time was to get the drainage trench dug. This way water could flow out of the trench in case there was a heavy rain.
Up until Saturday, we were able to dodge most of the rain. With blue sky appearing to the northwest, things were looking good. The afternoon wore on and still no major threat of rain. As a matter of fact, the weather service was just calling for showers with a cold front passing by over night.
Jo and I checked into the motel for the night. We were at the motel no more than one hour when all hell broke loose. Thunderstorms had quickly built over the area. And it rained, and rained and rained. It rained over 2" in less than an hour! All night I worried how the trench was going to look in the morning.
As soon as dawn hit, I drove out to the building site. My worst fears were realized. The trench had about 2' of water in it and some of the sides had fallen in. In other areas, silt had poured into the trench.
I didn't consider the consequences of equipment delays and heavy rain. Now I would have to return home wondering when things would dry out, what repairs would need to be made and when Russ could get back out to finish the trench so I could start laying the drain tile.
Needless to say this was one of those bad times.