Gray-Water-Fact-SheetCity of Cypress
Community Development: Building Division
5275 Orange Avenue
Cypress, CA 90630
(714) 229-6730
GRAYWATER
FACT
SHEET
The California Building Standards Commission (BSC) on July 30, 2009 adopted new code language
for residential graywater use that took effect August 4, 2009. This rulemaking is found in the California
Plumbing Code, Title 24, Part 5, Chapter 16A, Part I.
General Rules
• These new regulations apply to single or two-family residential buildings only.
• Kitchen sink, toilets, and diaper soiled water are not included in the definition of graywater.
• No ponding, spray, or exposed runoff of graywater is allowed.
• All systems must have an air-gap or suitable backflow prevention to protect the potable water system.
• Not for root crops or edible portions of food crops.
When is a Permit is Not Required
The only type of Graywater System that DOES NOT require a City building permit is a clothes washer
graywater system.
Eleven conditions apply to this type of graywater system that does not require a permit:
1. The design shall allow the user to direct the flow to the irrigation or disposal field or the building
sewer. The direction control of the graywater shall be clearly labeled and readily accessible to the
user.
2. The installation, change, alteration or repair of the system does not include a potable water connection
or a pump and does not affect other building, plumbing, electrical or mechanical components including
structural features, egress, fire life safety, sanitation, potable water supply or accessibility.
3. The graywater shall be contained on the site where it is generated.
4. Graywater shall be directed to and contained within an irrigation or disposal field.
5. Ponding or runoff is prohibited and shall be considered a nuisance.
6. Graywater may be released above the ground surface provided at least two (2) inches of mulch,
rock, soil or a solid shield covers the release point.
7. Graywater systems shall be designed to minimize contact with humans and domestic pets.
8. Water used to wash diapers or similarly soiled or infectious garments shall not be used and shall be
diverted to building sewer.
9. Graywater shall not contain hazardous chemicals derived from activities such as cleaning car parts,
washing greasy rags, or disposing of waste solutions from home photo labs or similar hobbyist or
home occupational activities.
10. Exception from a permit shall not be deemed to grant authorization for any graywater system to be
installed in a manor that violates other provisions of the Plumbing or Municipal Codes.
11. An operation and maintenance manual shall be provided. Directions shall indicate the manual is to
remain with the building throughout the life of the system and indicate that upon change of ownership
or occupancy, the new owner or tenant shall be notified the structure contains a graywater system.
Sample “ Laundry to Landscape” single fixture connection:
The following websites have additional information on graywater systems, graywater codes, and
the effects of laundry detergents and equipment used in graywater systems:
http://oasisdesign.net/
http://www.oasisdesign.net/greywater/laundry/index.php
http://www.hcd.ca.gov/codes/shi/Preface_ET_emergency_graywater.pdf
http://www.owue.water.ca.gov/docs/graywater_guide_book.pdf
Figure 7.6: Laundry to Landscape system
Outlet must attain this height before dropping down, to maintain water level in machine; irrigation abobe this height is possible but may shorthen pump life.
C) Vacuum breakusing swing or spring check valve, auto vent, or a 1/2" line,extending at least 6' (2m)above the tee at the high point of the line.
Ventthroughroof
Paving stonemarker5 galrecycledflowerpot
Former grade
9"+ cover over line 18"+ applicationdepth
PVC VERSION
PVC ver
si
o
n
HDPE v
er
si
o
n
Toseptic/sewer Garden hoseP-trapECO, HDPEVERSION
A) Washer pump
B) Diversion
D) Hose service connectionDisconnect washer, connect hose
H) Mulch basin
G) OutletsF) Distribution plumbling
E) Backflow preventerSee-through swing check valve
B)
B)C)
C)
1) Washing machine
drain hose
2) Hose clamp
3) Barb to pipe-thread
adapter
4) 1"3 - way diverter valve
5) 90O bend
6) 1" HDPE tubing
7) 1" PVC pipe
8) Standpipe
8
8
8
7
7
7
7
5
5
6
6
6'+
5
5555
5
5 5
2 2
2
2
222
2 2
1
1
12
4
4
4
3
3
3
3