Laundry and the Low-water Landscape: Greywater Harvesting and Reuse, Part II
Once I saw how easy it was to use greywater, I wanted to try it in other situations. I had already started tossing the rinse water from the dishes onto one of my backyard trees to see if it would survive. It thrived! By the end of the summer I had switched my soap to a “garden safe” brand, and dishwater was the primary source of irrigation for three trees and a shrub. Nearly the entire front yard was by this time planted with drought- tolerant plants, which are usually greywater-tolerant as well. (The exceptions were a few blueberry bushes under the front windows. Blueberries are sensitive to the higher pH of soap residues in greywater.) Why pay money for drinkable water if the plants would be just as happy with the secondhand stuff? I just needed more of it.
Because most of our house is on a slab foundation, I couldn’t re-plumb the drain lines to catch all the greywater the way some really green homes are plumbed. My hubby never would have approved that notion, even if it were practicable. Freshwater only costs about $2 – $3 per hundred cubic feet in our area, or around 25-40 cents for every hundred gallons. Harvesting greywater is ecologically virtuous, but (at present rates) it doesn’t save enough money to be worth spending more than about $10 on any one project. Sometimes even the free ones weren’t worth the potential consequences. For example, I tried scooping water out of the tub with buckets after bathing the kids, then carrying the buckets out to the yard. But that got the floor dirty and slick. Pennies saved on water wouldn’t make up for dollars spent on a broken limb. I had to be more creative than that, and more thrifty.
I took to searching YouTube for inspiration, for videos of people collecting and using greywater around their homes. Many of them utilized the rinse water from their clothes washing machines. Top-loading washers can use as much as 40 gallons of water per load (front-loaders use about half as much), so they are a good source of large volumes of reusable water. This is particularly true if you use a “garden safe” brand of detergent, although my early experiments with dishwater indicated to me that many plants did fine with the regular stuff. It just depended on the plant’s tolerance for the various salts and other chemicals that are in the detergent. My plants were nearly all adapted to saline soil conditions. Saline soils are common in deserts and climates with long dry seasons, so desert and drought-tolerant plants are virtually always greywater-tolerant plants as well. I was fairly confident I could use not just the rinse water, but the wash water as well, so long as I switched to the low-salt garden-safe variety. If I could just figure out a way to do it that did not involve hauling sloshing, 40-pound buckets of water out to the front yard on washing days. Surely I could be that clever.
Daily scanning of Craigslist eventually netted me some used plastic 55 gallon barrels for $5 apiece. I sawed off the top of one to make a huge open bucket (I really love reciprocating saws- just sayin’) and twisted a threaded hose bib into a hole I drilled near the bottom of the barrel side wall. I sewed a 3-foot circle of window screening into a flow-through “bonnet” to keep mosquitoes out of the water, then placed my new “surge tank” on top of a few cinder blocks stacked outside my laundry room. I was ready to start
reusing my washing machine greywater. Well, almost. Unless I wanted to do laundry with the drain hose from the washer running out an open window, I had to cut through the stucco of the laundry room wall, run a section of 2” PVC pipe through (angled to run into the tank), then patch up the holes and hang the washing machine drain hose in the PVC pipe. Did I mention my husband is tolerant? And helpful? I did most of the work myself, but even minor demolition and construction just goes better when someone with testosterone-influenced biceps is around to help out.
My initial results were promising. My front-load washer generated about 10 gallons of water per medium load, and the five members of my family generated about 5-7 loads of laundry per week. Whenever several plants in the yard needed watering, I put on my gardening clogs, went outside, opened up the tap, filled my watering can with murky-looking water, and watered my plants. I always washed my hands afterwards. Nothing died. Nobody got sick.
It worked, but it wasn’t ideal. The one-foot-elevation of the barrel didn’t provide much pressure, so the can filled sloooooowly, and I still spent too much time slogging back and forth to the front yard. Besides, greywater that sits for more than a day gets stinky, especially in warm weather. As soon as my backyard garden hose sprung a big enough leak that it was no longer useful for the kids’ sprinkler toys, I moved it to the spigot on the tank and ran the end under the side gate to the front yard. The low pressure of the tank didn’t cause any leakage, and I could simply leave the tap open and move the end of the hose from plant to plant as needed so the greywater never got a chance to grow fetid. This also meant that the greywater went directly to the root zone of plants, rather than splashing on the foliage where the ultra-fastidious might worry about spreading contamination.
Three years later, I still do. Nothing died. Nobody got sick. And I get compliments on the yard all the time.