Notes from Windward: #59

Tanks Alot - installing four more septic tanks

The truck arrives with the first 1,000 gallon septic tank
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When most people think of the challenges inherent in building an intentional community, they rarely seem to have septic tanks in mind. It's just not the sort of thing that most people place high on their list of things they're looking for when they set out to learn about ICs.

I think that part of the reason for this is the degree to which people today take their life support systems for granted. In the city, sewage disposal is just something that exists; you flush the toilet, pay your utilities bill and forget about it. Things don't work that way in the country. Out here, we have to construct, operate and maintain our sewage, water and power systems, and fix them when they break.

As part of our program to construct more and better housing, we're installing a series of septic systems. The ones that these pictures tell about are designed to handle the waste water coming from four 16'x20' two story A-frame cabins that we'll be constructing over the next couple of years. Before we ever start nailing boards together, there's a lot of work that has to be done first to bring water, power, phone, twisted-pair and sewage services to each cabin site.

One of the tanks installed among the trees
And, to make the matter even more complex, we're determined to do these things in ways that have the least adverse impact on our land, and the forest that covers it. The quick and cost-effective way to go about it would be the build the cabins in a cluster on flat, open land, or to bulldoze enough trees to create such a spot. We're not willing to do that because we want the flat, open land to remain as gardening/food growing land, and to keep as much of our forest intact as we possibly can. That means that we have to be innovative, creative and patient. As with most things in Intentional Community, success is the accumulation of attention to detail.

The cabins are strung out along a slope that overlooks and encircles the main area. The crew at the local Health Department were very helpful and went out of their way to help us come up with a cost-effective system which met the code requirements. The solution we arrived at was to provide each cabin with its own 1,000 gallon septic tank, but to then combine the effluent stream so that the two tanks were served by a single drain field. This lowered the costs, and greatly reduced the number of trees that had to be removed.

Lowering the tank into place
As you can see in the picture, we've kept the forest as intact as possible, and I was very impressed with the skill and dexterity with which the driver of the delivery truck was able to maneuver that 11,000 pound tank through the trees and into the hole. While we strive to do things ourselves, there are times when there's no substitute for bringing in the heavy iron.

The only "adventure" came when John "found" the main water line with the backhoe. I had misremembered where Mike had installed it, and it turned out to be about 10 feet to the south of where I thought it was. The rupture of the water line was inconvenient, but we would have had to tap into it eventually in order to install the water lines for the new cabins. We'd planned on doing this task later, but sometimes tasks have a way of moving themselves to the head of the line.

The new water distribution manifold
Installing these systems was a good example of how timing works on our projects here at Windward. There's a narrow window when this work can be done easily. In March and April, the ground is too soft to support the heavy truck that has to deliver and set them in place, and too wet to allow the backhoe to dig the trench for the drain field. When soil like ours is worked in the wet state, the clay tends to compact and form a solid barrier that's essentially water proof - definitely not a characteristic that you want in a drainfield.

Come August and September, the ground is so dry that you can drive a 30,000 pound cement truck across it and not leave a mark, but it's also way too hard to be able to dig effectively. Last year when I used our backhoe to dig the four foot deep test holes that the inspectors needed so they could determine the holding/draining capacity of our soil, something which they need to know in order to determine how large a drainfield is going to be needed, the backhoe had a hard time. When the bucket is lifting the backhoe off it's rests, instead of penetrating into the ground, you know you've got some really hard ground.

We've already used this window of "digability" to get the trenches dug for the 240 VAC power and water lines, and July will be when we bring in the trackhoe to dig the deep trench for the 7,200 VAC undergroung power service lines. By the time that's done, we'll be through with digging until the rains return in October.

John proudly displays the "Green Tags"
Once the work is done, but before it's covered up, the inspector has to check the work. That mostly involves checking to insure that the septic tank was installed correctly, and that the drain field was level and as long as was called for in the permit. Once those concerns were satisfied, we were reward with the coveted "green tags", which as you'll note in the picture really are green.

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