Permaculture Design Course
Day 5, Session 4: Greywater in CA
Kirstie Stramler
http://Permaculture.TV
Day 5 Topic: Greywater
o What is Greywater?
o Greywater in CA: History, Code, Prospects
o Overview: Types of Greywater Systems
o Highlight: Laundry to Landscape
o Highlight: Branched Drain System
o Greywater Resources
What is Greywater?
In California, Greywater is defined as water from
specific house fixtures, such as:
o Washing machines
o Showers
o Baths
o Bathroom Sinks
But not from ‘Blackwater’ sources:
o Kitchen Sinks
o Toilets
From Laundry to Fruit Tree!!!
Greywater in CA: History, Code, Prospects
o Prior code required 9” outlet depth
o Soap study shocker
o Grassroots + Art = Gov’t Rethink
o Code as of Aug 2009, Official Jan 2010
o Current Permitting Actions in CA
o Likely Future of Greywater in CA
New CA Greywater Code: Intent
1. Conserve water by facilitating greater reuse of laundry,
shower, lavatory and similar sources of discharge for
irrigation and/or indoor use.
2. Reduce the number of non-compliant graywater systems
by making legal compliance easily achievable.
3. Provide guidance for avoiding potentially unhealthful
conditions.
4. Provide an alternative way to relieve stress on a private
sewage disposal system by diverting the graywater.
New CA Greywater Code: Specifics
o Need a well-marked SWITCH betw/ grey & sewage
o Don’t store it more than 24 hours
o Minimize human & animal contact w/ greywater
o Discharge must be 2” under mulch/soil/rock/solid shield
o No hazardous chemicals of any sort down the drains; no
diapers or similarly infectious materials
o Can’t cross plots from discharge point + 1.5” to boundary
o No permit: area too small or subject to runoff or ponding
o System = f(location, discharge capacity, soil type, and
groundwater level)
o Can’t irrigate root crops
o Can’t irrigate edible parts of crops that touch the soil
o Huge: washing machine pump NOT part of the system!!!
Greywater in CA: History, Code, Prospects
o Prior code required 9” outlet depth
o Soap study shocker
o Grassroots + Art = Gov’t Rethink
o Code as of Aug 2009, Official Jan 2010
o Current Permitting Actions in CA
o Likely Future of Greywater in CA
Current Permitting Actions in CA
As of June 2007:
Berkeley First Greywater System Permit (Now 5)
As of May 2010:
LA First Greywater System Permit
As of July 2010:
Oakland First Greywater System Permit + Checklist
2 in Marin this summer…
There are probably more!
Greywater in CA: History, Code, Prospects
o Prior code required 9” outlet depth
o Soap study shocker
o Grassroots + Art = Gov’t Rethink
o Code as of Aug 2009, Official Jan 2010
o Current Permitting Actions in CA
o Likely Future of Greywater in CA
Supply Issues…
Likely Future of Greywater in CA
Given…
(1) Aging, brittle water infrastructure
(2) Increasing potable water scarcity + aquifer drawdown
(3) Inability of sewer systems to manage peak flow levels
Likely Future of Greywater in CA
Given…
(1) Aging, brittle water infrastructure
(2) Increasing potable water scarcity
+ aquifer drawdown
(3) Inability of sewer systems to manage peak flow levels
Likely Future of Greywater in CA
Given…
(1) Aging, brittle water infrastructure
(2) Increasing potable water scarcity + aquifer drawdown
(3) Inability of sewer systems to manage peak flow levels
Likely Future of Greywater in CA
Given…
(1) Aging, brittle water infrastructure
(2) Increasing potable water scarcity + aquifer drawdown
(3) Inability of sewer systems to manage peak flow levels
It follows that government is going to have to invest in…
(1) Replacing aging infrastructure
(2) Costly and polluting reclamation plants
(3) Costly and energy inefficient desalination plants
Guess who is going to be paying for all of that?!
Therefore the solution is to…
GO GREY!!!
Day 5 Topic: Greywater
o What is Greywater?
o Greywater in CA: History, Code, Prospects
o Overview: Types of Greywater Systems
o Highlight: Laundry to Landscape
o Highlight: Branched Drain System
o Greywater Resources
Overview: Types of Greywater Systems
o Laundry Drum
o Laundry to Landscape
o Branched Drain
o Drum with Effluent Pump
o Sand Filter to Drip Irrigation
o Constructed Wetland
o Constructed Wetland to Drip Irrigation
Overview: Types of Greywater Systems
o Laundry Drum too high maintenance
o Laundry to Landscape no permit required!!!
o Branched Drain ultra functional, no-clog system!!!
o Drum with Effluent Pump only if necessary
o Sand Filter to Drip Irrigation ultra fancy $$$
o Constructed Wetland often an arid subtropics fail
o Constructed Wetland to Drip Irrigation ditto
Day 5 Topic: Greywater
o What is Greywater?
o Greywater in CA: History, Code, Prospects
o Overview: Types of Greywater Systems
o Highlight: Laundry to Landscape
o Highlight: Branched Drain System
o Greywater Resources
Highlight: Laundry to Landscape
Highlight: Laundry to Landscape
Collection Plumbing: 3-way valve & auto-vent
Highlight: Laundry to Landscape
Distribution plumbing, testing, receiving landscape
Highlight: Branched Drain System
Idealized schematic to demonstrate distribution plumbing
Highlight: Branched Drain System
How our distribution plumbing actually looked …
Highlight: Branched Drain System
Pre-existing
plumbing
Collection plumbing,
labeled switch/pipes,
& actuator atop valve
Greywater Resources
Greywater Information Central
www.oasisdesign.net/greywater/
Greywater Workshops & Installer’s Course
www.GreywaterAction.org
One-stop Shopping & Assembly Blueprint PDFs
www.cleanwatercomponents.org
Google Tech Talk: How to Implement a Greywater
System for Your Garden
www.youtube.com/watch?v=t1DfNlxlk-A
Laundry Drum System
Berkeley Greywater Constructed Wetland
Digging & Building the Wetland (2006)
Constructed Wetland
June & Sept 2007
Residential Backyard Wetland Design
