Greywater Glossary of Terms

Quick Answers

 

Official Greywater  Definitions

 

Clothes Washer System. A graywater system utilizing only a single domestic clothes washing machine in a

one- or two-family dwelling.

 

Complex System. Graywater systems that discharge over 250 gallons per day.

D

Disposal Field. An intended destination for graywater including but not limited to a mulch basin, leach line

or other approved method of disposal.

Graywater. Pursuant to Health and Safety Code Section 17922.12, "graywater" means untreated

wastewater that has not been contaminated by any toilet discharge, has not been affected by infectious,

contaminated, or unhealthy bodily wastes, and does not present a threat from contamination by unhealthful

processing, manufacturing, or operating wastes. "Graywater" includes wastewater from bathtubs, showers,

bathroom washbasins, clothes washing machines, and laundry tubs, but does not include wastewater from

kitchen sinks or dishwashers.

Graywater System. A system designed to collect graywater and transport it out of the structure for

distribution in a Irrigation or Disposal Field. A graywater system may include tanks, valves, filters, pumps or

other appurtenances along with piping.

 

Irrigation Field. An intended destination for graywater including but not limited to a drip irrigation system,

mulch basin, or other approved method of dispersal for irrigation purposes.

 

Mulch. Organic waste material including but not limited to leaves, prunings, straw, pulled weeds and wood

chips. . Mulch shall be permeable enough to allow rapid infiltration of graywater.

 

Mulch Basin. A type of irrigation or disposal field filled with mulch or other approved permeable material of

sufficient depth, length and width to prevent ponding or run off. A mulch basin may include a basin around a

tree, a trough along a row of plants or other shapes necessary for irrigation or disposal.

 

Treated Graywater. Nonpotable water collected and treated on-site suitable for direct beneficial use. The

level of treatment and quality of the treated graywater shall be approved by the Enforcing Agency.

 

Simple System. A graywater system serving a one- or two-family dwelling with a discharge of 250 gallons

per day or less. Simple Systems are when you exceed a Clothes Washer System and/or a Single Fixture

System.

 

Single Fixture System. A graywater system collecting graywater from one plumbing fixture or a single drain

which collects graywater from more than one fixture in a one- or two-family dwelling.

 

Treated Graywater. Nonpotable water that has been collected and treated on-site, and is suitable for direct

beneficial use. The level of treatment and quality of the treated graywater shall be approved by the public health Authority Having Jurisdiction.

 

 

  • COLLECTION PLUMBING: This is the plumbing that connects to your existing drain lines and divert the greywater away from the septic lines. These pipes sends it toward the landscape and end where they leave the house. This needs to be a high quality installation, performed by a professional who understands greywater.

    DISTRIBUTION PLUMBING: These irrigation lines begin where the Collection plumbing leaves the house, and spread the greywater throughout the landscape. This is a whole different type of pipe, specialiy designed to carry greywater, and has lowest environmental impact of any available piping. This is a job for a greywater system designer, someone who understands the complete process, and is dedicated to the"keeping it simple" view that allows for a sucessful, sustainable out come.

  • BLACKWATER: wastewater from the toilets, laundry with diapers and disposal of household chemicals

    • GREYWATER SYSTEM DESIGNER:  someone who has studied graywater  and understands all aspects of the process.  Plumbers often don’t get it and landscaper are used to a whole different type of irrigation and  besides most would charge much, much, more than is necessary.  A greywater systems designer should inspect your current plumbing  to see if a greywater connection is feasible. Then inspecting the lay of the land and the landscaping surrounding your house to see how the greywater would best be used. 

    ADAPTER: Any plumbing or drip irrigation part which
    connects one size pipe or part to another. Often used to refer to
    the female fitting, whether glued or threaded, which joins
    different parts together.
    ACTUATOR: A 24V DC motorized value, used to
    automatically control valves. Unlike a solenoid, this valve’s
    opening and closing is powered by the motor, not the pressure
    in the pipe. Because it works without any water pressure in the
    pipes, it is the most practical valve for many graywater
    systems.
    AEROBIC SOIL: A well drained soil with sufficient pore space
    to allow plenty of air circulation. The pore space is usually
    dependent upon the texture (sand is most open) and a
    reasonable amount of organic matter and humus.
    ANIONIC SURFACTANTS: A cleaning agent, most commonly
    some form of sodium salt. Usually found in high sudsing
    detergents (see sodium chloride).
    BALL VALVE: A valve which has a globe shaped rotating
    interior. The solid globe has a circular tunnel through it. When
    the handle of the valve is rotated, the solid portion of the ball
    cuts off the flow of water. Another rotation lines up the tunnel
    and water flows through the valve. Ball valves are often found
    at the discharge port of quality y-filters. Because ball-valves
    shear off any contaminants and because they don’t easily wear
    out like gate valves, they are the preferred valve for graywater
    systems.
    BEACHFRONT AREAS: Areas with a sand profile verses a
    soil profile.
    CENTRIFUGAL PUMP: A pump installed outside the surge
    tank, not submersed in the graywater. The centrifugal pump
    along with a diaphragm pressure tank should be housed in or
    under a weatherproof structure.
    CHECK-VALVE: A backflow preventer which stops any water
    siphoning back toward the house. Often not legal as the only
    backflow preventer in potable-water drip system. Must be
    coupled with some form of atmospheric vacuum breaker.
    DRIP: A style or technology of irrigation where a tiny trickle of
    water is slowly applied to the soil.
    DRIP HOSE ADAPTER: The first fitting after the main
    assembly of a drip irrigation system. Almost always an FHT
    (female hose thread) swivel X drip hose adapter. The female
    hose threads of the swivel go on to the male hose threads of a
    hose-bib or a transition nipple. The swivel action makes it easy
    to quickly add or remove this fitting. The other side of the
    adapter is either a slip (glue), or compression, depending on the
    system.
    DRIP LINE: A length of solid drip irrigation hose or in-line
    emitter tubing.
    DRIPLINE: The width of a tree’s or shrub’s foliage, where
    water would drip off the edge of the canopy. Not an indicator
    of the width of the root system as roots grow from one half to
    three times wider than the dripline.
    DUAL PLUMBING: A permanent separate set of pipes for all
    the graywater sources in the home.
    ELBOW: A fitting which allows drip hose or pipe to make 90
    degree turn.
    EMITTER: The little gizmos attached to or built in to solid
    drip irrigation hose which control the flow of water to the soil.
    There are many name brands that basically fall into four
    generic styles or technologies: single diaphragm, double
    diaphragm, tortuous (or complex) path, or simple orifice.
    END CAP: The fitting added at the end of a lateral to make it
    easy to open the tubing for draining or flushing. Has a female
    hose thread cap with a washer which threads on to the male
    hose thread fitting. The other end will be either a compression,
    insert or other opening, depending on the system you use.
    EVAPOTRANSPIRATION (ET): The loss of water from a
    plant or crop via transpiration (exhaling) by foliage and
    evaporation from the plant’s and soil’s surface. The ET rate is
    influenced by humidity, rainfall, slope aspect, wind speed,
    temperature, plant care and soil.
    FIGURE EIGHT END CLOSURE: A simple end closure
    which involves threading the end of the drip hose through one
    side of the figure eight, bending over the end of the end of the
    drip hose and securing the bent end inside the other half of the
    figure eight.
    FILTER: A device with a screen (cheap, poor quality models
    have plastic screens) which is used to trap any particulates, dirt,
    or scum before it can enter the drainfield or clog the drip
    emitters. An essential component of all graywater drip systems.
    FHT: Plumbing shorthand for a female iron pipe thread.
    FLAPPER CHECK VALVE: A valve that prevents any water
    from siphoning back into the surge tank.
    GFI: A ground fault interrupt outlet. All sump pumps must be
    plugged into a GFI outlet.
    HEAD: A pump’s head is the gross difference in elevation
    which it pumps. As a safety factor, the head for a graywater
    system is determined by adding the total changes, both up and
    down, in the elevation from the surge tank to the point of
    disposal. To this figure add at least 15% more feet of the total
    head.
    HOSE-BIB: Another name for a garden faucet. The standard
    gizmo on the pipe sticking out of the house’s exterior wall or
    on top of a metal water pipe in the yard and onto which the
    garden hose is attached