Sunday, October 10, 2010

Grey Areas

Oh Goodness. I'm just going to jump right into the deep end here.

The architect we've been working with has come up with a great basic layout for the house that fits well with our dreams. It's about 800 square feet and entirely open with a cozy, cabin-like feel that really connects to its surroundings. It blurs the lines between indoor and outdoor spaces with large doors and lots of covered patio space, making the relatively small footprint into what we ultimately want it to be: an extension of the land around it, providing just the right amount of warm, dry space to compliment the garden and front "lawn" area it will be facing, and the dark, misty woods behind it. While the sketches are being reviewed and notated by an engineer, who will calculate loads and determine what crucial elements we can use our own lumber for, we've been sent on a mission of determining our septic needs with the state and county so they can be incorporated into the site plan for approval.

As I've alluded to before, this is one of the bigger challenges facing our congenial relationship with the local inspectors and health department. If we're going to get approval to build a house without a septic system, which is unprecedented in this area of the country, we're going to need one hell of a convincing proposal, backed up with a whole bunch of research. Such has been our week. The research, I won't lie, is kind of fascinating. I know a whole lot more about cyanobacterial growth, evapotranspiration rates and soil percolation than I ever thought I would want to. Still, I feel very much over my own head in all this. For your enlightenment and my own processing, I would like to offer a brief summary of our current position:

Please stop here if you are prone to headaches....

Waste water is broken down into two categories: grey water and black water. Black water is highly contaminated and dangerous waste, grey water is lightly contaminated and can potentially be repurposed. The line gets drawn differently in different areas. Luckily for us, our state breaks it down like this: toilet - black water, everything else - grey water.

With our composting toilet, we eliminate all black water, which is pretty awesome. Not only do we cut down drastically on our water usage, we confine dangerous pathogens and bacteria to a self enclosed barrel which uses natural processes to break them down into a nitrogen-rich compost, which we can return to the earth to continue it's cycle as plant food. All we have to deal with is our grey water, which we have a minimal amount of to begin with.

Since we will have no dishwasher, low-flow shower and sink faucets and our bicycle powered washing machine (which uses less than half as much water as a traditional front load model), we've calculated our annual water usage to be around 7,665 gallons. That's about one tenth the average household's. With our 2,200 square foot garden downhill from the house, it's easy to imagine an
intricately branched system of pipes and drip hoses using gravity to deliver our safe grey water to eager beds of veggies, herbs and fruits. Any additional water the plants may want in summer months can easily be covered by a rainwater catchment system. Using the size of our roof and the average annual rainfall for our area, it's easy to calculate our rain catchment potential in an average year. Turns out western Washington is a pretty wet place. Provided we had the capacity to contain it, we could easily capture 20,000 gallons of water PER YEAR. TWENTY THOUSAND GALLONS. Again, our entire household will only use eight thousand. With a large enough cistern and a pump, we're hoping to eventually live entirely off of captured rainwater. No water bill.

The real problem comes in the winter, when we are using water that the garden absolutely does not need. Grey water can't be stored, it has to be dispersed into the soil immediately to prevent any bacterial growth. If it's not going to go into garden beds, we'll need to have an alternative area that can absorb the water quickly, even with the high water tables the rainy months give us. There are options, like mulch beds around water loving plants, intentionally designed wetland ecosystems, or even greenhouses designed to evaporate the water quickly. We're not sure what option will be best for us. For the love of God, chime in if you know more about this that we do!

The state of Washington's Department of Health is currently reviewing new legislation on grey water issues, and will rewrite existing laws, after examining the more lenient laws of California and Nevada, by the first day of next year. It's still assumed that a sewage or septic line will be required of any grey water collection system, (according to the helpful folks at, so our system will still need to be accepted as an experimental alternative system by the state, and we will most likely have to sign a waiver making us responsible for any consequences. I just hope we can compile a convincing argument soon, so we can go ahead and get our plans approved for the house and start working.
What have we gotten ourselves into?