What shouldshouldnt I irrigate with graywater

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Graywater Recycling
What should/shouldnt I irrigate with graywater?
Save Money, Water The Environment
You MAY irrigate fruit trees, ornamental trees,
groundcover and lawns. You MAY NOT irrigate root
or leafy vegetables or other food crops that
touch the soil, for health and safety reasons.
Furthermore, you MAY NOT use graywater for spray
irrigation, or allow it to pond or run-off on
the ground. The discharge point of the graywater
must be covered by at least 2 inches of mulch,
rock, or other cover material to minimize human
contact.
What is graywater?
What is World Usability Day?
Graywater is wastewater generated from laundry
and bathing/showering, but NOT from the toilet.
Comprising of 50-80 residential wastewater,
graywater gets its name from its cloudy
appearance and is neither fresh (white, or
potable, water) nor heavily polluted (black, or
sewage, water).
Its about making our world work better. Its
about Making Life Easy and user friendly. It
is an initiative from the Usability
Professionals' Association (UPA) to ensure that
services and products important to human life are
easier to access and simpler to use. Each year,
events are organized to raise awareness for the
general public and train professional in the
tools and issues central to good usability
research, development and practice. For more
information, see www.worldusabilityday.org
Why should I be interested?
Since graywater consists of at least 50 of
residential water, an opportunity exists for
converting this wastewater and its nutrients
into landscape use. Conserving water in this
manner leads to considerable financial savings
and to a more ecologically sustainable
community. Environmentally, water conservation
has become an important concern due to drought
and limited availability of fresh water. Use of
graywater will Reduce demand on water
supplies, Enhance groundwater recharge,
Reduce energy use and chemical pollution due to
less reliance on sewage treatment systems.
Where can I find more information?

• Visit www.sdhfes.org
• You will find
• List of graywater devices and systems,
• Cost savings calculators,
• Advices and tips,
• Supplemental information on plants and soaps,
• List of plumbers, etc.

What is San Diego Chapter of the Human Factors
and Ergonomics Society?
SD-HFES is a local chapter of the national
professional group, the Human Factors and
Ergonomics Society (HFES). The mission of HFES is
to promote understanding and development of
systems / devices that complement the human
characteristics of its operators, resulting in
safer work processes and more usable
tools. Members of the local chapter come from
many
This pamphlet is for informational purposes
only. The authors will not be held civilly liable
for the use, non-use, or misuse of the
information provided. Always consult a qualified,
licensed plumber before working on your homes
plumbing system.
Financial benefits according to the California
Plumbing Code, a typical three-bedroom home
generates 160 gallons of graywater per day or
58,000 gallons per year. A family of four could
potentially reuse 22,000 gallons of water per
year from its laundry system alone, which is
equal to the size of a large residential swimming
pool! (hcd.ca.gov/news/release/Graywater7.31.09.pd
f)
different backgrounds, including
Industrial-Organizational Psychology,
Experimental Psychology, Human Factors,
Forensics, and Computer Science.
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systems without a construction permit in your
one- or two-family dwelling. However, you must
follow certain rules. Systems exempted from a
construction permit must be one of the following
types 1. A CLOTHES WASHER system uses only a
single domestic clothes washing machine in a one-
or two-family dwelling. 2. A SINGLE FIXTURE
system collects graywater from (a) one plumbing
fixture or (b) a single drain which collects
graywater from multiple fixtures, in a one- or
two-family dwelling. You must be able to direct
the graywater to the sewer. The mechanism that
changes the direction of the water must be
clearly labeled, and it must be easily
accessible. The graywater system MAY use water
from showers and bathtubs, bathroom sinks,
laundry tubs and a washing machine but water
used to wash diapers must be diverted to the
sewer. The graywater system MAY NOT use water
from toilets, kitchen sinks, or
dishwashers. Other systems that exceed the
clothes washer system or the single fixture
system, DO require a permit. Before you install
a graywater system in any type of dwelling,
please see State of Californias Graywater
Standards for complete rules (hcd.ca.gov/codes/sh
l then click on the link to Title 24 California
Building Standards Code). Also, local
municipalities MAY enact tougher rules than the
States so always check before you install. In
the County of San Diego, the authority on
graywater systems is the Department of
Environmental Health, which can be reached at
858-495-5572.
What can I do in my house?
Will irrigation with graywater harm my plants?
Graywater systems range from putting a hose from
the bathtub through the window to the garden, to
a branched drain system. Some systems can be
generally installed by the homeowner, others may
require a plumber. Please see our website for
list of plumbers and advices and tips.
Graywater is highly alkaline due to the basic
nature of soaps and cleaning chemicals. Neutral
water has a pH of 7.0 and San Diegos municipal
water supply runs over 8.0, yet graywater can
have pH over 9.0. Therefore, it is best used on
established plants that can handle alkaline
conditions. Fortunately, this includes many of
our coastal California natives as well as desert
plants.
Will it affect my water pressure?
Visit the native plants section of local
nurseries to view the selection. Also, most
graywater contains phosphorus, potassium and
nitrogen, all of which are nutrients that benefit
plants. If possible, choose soaps that do not
contain sulfites or chlorine. Plants in pots or
plants that require acidic conditions -- like
azaelias, rhododendrens or camelias -- would not
be able to tolerate the high alkaline level on a
regular basis. For these plants, graywater may
cause poor (or destroyed) root and plant
circulation, thus reducing the plants ability to
transport water and nutrients. Alkaline
conditions may also cause leaf burn. Thus,
watering alternately with graywater and fresh
water is recommended. Supplemental information
on plants and soaps, visit www.sdhfes.org
Absolutely not. Graywater systems handle water
post-use. Nothing in these systems interferes
with the fresh water that is delivered through
your faucets and shower heads. Other
water conservation options such as low-flow
shower heads and toilets can be used in
combination with a graywater system.
Do I need a permit?
Multi-family dwellings - permits are
required. One- and two-family dwellings -
permits are NOT required for certain systems.
Recently, the State of California adopted
emergency graywater regulations effective
8/4/09 and to remain in force for 180 days or
until made permanent. Under these emergency
regulations, you can install certain graywater