At TBL, we advocate green technology on all our projects. We specify solar collectors (water and photovoltaic), solar shingles, cisterns, greywater systems. drip irrigation systems and pool covers. In 2014, Tim hired Greywater Corps to install a greywater system in his own house…to test the waters, if you will.
Greywater recycling reuses household water to irrigate landscaping and trees. A Laundry-to-Landscape systems does this without a tank, filter or pumps. Tim’s home has drought-resistant herbs, trees, shrubs, grasses and flower instead of a lawn – yet the plantings he chose still need some irrigation. The City water he uses indoors is an inexpensive and available resource for reuse in his gardens outdoors. The advantages of greywater systems are clear: make double use of the water we already use, spend less cash, and consume fewer resources.
How does it work?
In Tim’s Laundry-to-Landscape Greywater System, the water from his laundry, tubs/showers, and lavatory sinks are diverted from sanitary sewers to mulch pits (24” diameter and 24“ deep pits, lined with mulch) near his biggest water consumers: olive, pomegranate, apricot and citrus trees. All of the water reaches the mulch pits via gravity (but the Laundry provides a small assist when it pumps water out of the washer).
Is it expensive?
Until we learn how to bathe and clean our clothes without water, greywater is a precious, constant resource. Affordable infrastructure puts them within reach of most homeowners.
The cost to install a Greywater Corps system runs between $2,000 and $9,000. By comparison, systems with tanks, filters and pumps can cost up $30,000 and require frequent maintenance.
Do I need a permit?
Tim’s system was installed under Chapter 16A of the California Plumbing Code, “Nonpotable Water Reuse Systems”.
This system requires mindfulness. Soaps, shampoos and Laundry detergent must be chosen with care, to avoid over-salting the gardens with any products with sodium in the ingredient list. Look for cleaning products labeled “biocompatible” or “biodegradable”. Body soaps and shampoos are rarely harmful to plants. For Laundry, try Oasis Laundry Liquid, Trader Joes Liquid Detergent or Bio Pac Laundry Liquid. And always install a diverter near the Laundry in case you plan to use chlorine bleach – so you can send that water into the sewer.
Does it work everywhere?
Maybe not. A tankless Laundry-to-Landscape system needs gravity. It’s very difficult to make water flow uphill – if that’s where you keep your garden. Also, Tim irrigates his vegetable garden with potable water for two reasons:
- Greywater isn’t recommended for root vegetables.
- The mulch pits don’t effectively serve the smaller, individual plants in his vegetable patch.
What’s the downside?
Tim did experience two disadvantages:
- He tried to use greywater on his vegetable garden for a year. FAILURE. His household doesn’t generate enough water for vegetables – and the mulch pit system isn’t sophisticated enough for numerous small plants.
- By diverting most of the water from his sanitary sewer, he created a problem. When roots blocked his sewer line in 2015, the lowest points (tubs and showers, where back-up usually occurs) weren’t connected to the sanitary sewer. So the waste backed up through the toilets – requiring extensive remediation.
Tim believes the water shortage in Southern California will only get more serious. Other parts of the world are experiencing droughts, too. Clean water is the Earth’s most precious commodity. While Tim saves approximately $30 to $50 a month on his water bill by reusing his water, it’s not the only reason to have an L-to-L home system. Can we take less clean water from our rivers and lakes and leave more for fish and fowl? Can we spend less of our resources making landscape water potable, treating it with chemicals and pumping it from faraway places? Can we leave the Earth greener than we found it?
Thinking green has guided TBL well in the past 22 years. Tim, Kirk and Laura are LEED Accredited Professionals. We completed a LEED Gold-rated home in 2015. We have found better ways to insulate homes (with open cell foam insulation) and better ways to ventilate them (with passive systems). We have discovered hyper-efficient heating and cooling systems and required renewable, local materials in our homes. We require recycling of construction waste and demolished materials. TBL has even started to design Lexus batteries systems to serve as temporary house power in peak hours and power failures. The future of green technology in TBL homes is bright. What will the next 22 years of green tech bring? We’re excited to learn – and to share with you.
(All images courtesy of Greywater Corps)