In Central Texas, any opportunity to reuse water should be taken because we are using up more water than we have. Not only is our water supply dwindling, but also pumping water from place to place requires extra energy. In Austin we typically use 35 percent of our water for landscape irrigation. If we used graywater for this purpose, it would conserve treated water and save energy.

Recent legislation has made it possible for home and business owners to collect and reuse graywater onsite for surface and subsurface irrigation needs.

Graywater is defined as the wastewater produced from baths and showers, and lavatory sinks. The wastewater generated by toilets, kitchen sinks, dishwashers, and diaper washing in clothes washers is called blackwater .

(Excerpted from R. Waskom, "Graywater Reuse and Rainwater Harvesting," Colorado State University. www.ext.colostate.edu/pubs/natres/06702.html )

Graywater refers to the reuse of water drained from baths, showers, washing machines, and [hand-washing] sinks (household wastewater excluding toilet [and food] wastes) for irrigation and other water conservation applications. Graywater is of lesser quality than tap water, but generally of higher quality than blackwater, or water from sewage systems. Water from the kitchen sink, garbage disposal and dishwasher is considered blackwaterÖbecause of high concentrations of organic waste and the difficulties of reusing this water safely.

The most obvious advantage of domestic graywater use is that it may potentially replace other water used for landscape irrigation. Filtered graywater is most suitably used for subsurface irrigation of nonedible landscape plants. Not only does its use on landscapes conserve treated tap water, but graywater may also benefit plants because it often contains nutrients such as nitrogen or phosphorus. Graywater use may [also] offer financial savings to already overburdened municipal sewage treatment facilities, because graywater use diminishes sewer flows, thereby lessening the need to expand such facilities.

Graywater systems vary from simple, low-cost systems to highly complex and costly systems. Sophisticated systems treat graywater prior to disposal using settling tanks and sand filters in order to remove pollutants and pathogens.

HB No. 2661, enacted in September 2003, is an amendment to the state Water Code establishing graywater reuse as a viable water conservation method. The Texas Commission on Environmental Quality (TCEQ) is responsible for adopting and implementing standards of graywater use, and must do so by June 1, 2004.

Below is a list of general parameters established by the Bill that one should be aware of:

• Graywater can be used in agricultural, domestic, commercial, and industrial situations, in accordance with applicable Health and Safety codes.
• A permit is not required for the domestic use of up to 400 gallons of graywater daily if the following criteria are met:
  • Graywater originates from a private residence,
  • Graywater is used by the occupants of that residence for gardening, composting, or landscaping at the residence,
  • Graywater is collected with a system that overflows into a sewage or on-site waste treatment and disposal system,
  • Graywater is stored in tanks that are clearly labeled as non-potable water, restrict access (especially to children), and eliminate habitat for mosquitoes and other pests,
  • Graywater system uses piping that is clearly identified as non-potable water conduit,
  • Collection of graywater does not generate ponds or pools,
  • Collection system does not create runoff across property lines or onto impervious surfaces,
  • Graywater is distributed by a surface or subsurface system that does not spray into the air.
• Builders are encouraged to install plumbing in all new houses in a manner that allows graywater collection and reuse.
• The installation of subsurface graywater systems around the foundations of new houses is encouraged so as to minimize foundation movement and cracking.
• The review and approval of on-site sewage disposal systems is to be handled by TCEQ.

See "Engineers-Professional" in the Yellow Pages

Community Environmental Services, Inc.
2101 South IH-35, Suite 400
Austin, TX 78741
(512) 443-2733
www.ces-txvi.com

Robert Morris Inc.
P.O. Box 1688
Cedar Park, TX 78630
(512) 267-0688
rmorriss@texas.net
Septic engineer experienced in alternative systems

David Venhuizen
5809 Gateshead Dr.
Austin, TX 78745
(512) 442-4077
waterguy@ix.netcom.com
Septic engineer experienced in alternative systems

See "Septic Tanks" in Yellow Pages

Aerobic Wastewater Systems
P. O. Box 163263
Austin, TX 78716-3263
(512) 263-2219
Aerobic system

Clivus Multrum, Inc.
15 Union St.
Laurence, MA 01840
(800) 962-8447, 800-4-CLIVUS
www.clivusmultrum.com
Compost/graywater system

Drip-Tech Wastewater Systems
PO Box 5814
Austin, TX 78763
(512) 329-0066
Drip wastewater irrigation systems

Ecos
50 Beharrel St.
Concord, MA 01742
(978) 369-3951
www.ecological-engineering.com
Compost/graywater systems & components

Jade Mountain Inc.
P.O. Box 4616
Boulder, CO 80306
(800) 442-1972
www.jademountain.com
Graywater systems

Austin-Travis County Health Department
15 Waller St.
Austin, TX 78702
(512) 469-2022
www.ci.austin.tx.us/wri

City of Austin Water Conservation Program
P.O. Box 1088
Austin, TX 78767
(512) 499-2199
www.ci.austin.tx.gov/watercon
Information, "Small Flows" newsletter

National Small Flows Clearinghouse
P.O. Box 6064
Morgantown, WV 26506-6064
(800) 624-8301
www.estd.wvu.edu/nsfc

Texas Commission on Environmental Quality
(512) 239-1000
www.tceq.state.tx.us

Texas On-Site Insight
Write to: Texas Water Resources Institute
Texas A & M University
301 Scoates Hall
College Station, TX 77843
(409) 845-1851 or (409) 845-8571
www.towtrc.tamu.edu
Free newsletter focusing upon on-site wastewater disposal

Additional Information

Chapter 12-4 of the 1992 Code of the City of Austin

"Graywater Task Force Report," City of Austin Resource Management Department, 1985.

Publications

Reed, Sherwood C., E. Joe Middlebrooks, Ronald W. Crites. Natural Systems for Waste Management and Treatment , 2nd edition. McGraw-Hill: New York, 1994.

Brittain, Richard G., DeCook, K. James, and Foster, Kennith E. Water Harvesting and Reuse: Designing an Urban Residential Demonstration . Office of Arid Lands Studies, College of Agriculture, University of Arizona, Tuscon, November, 1984.

"How to Use Graywater: Guidelines to the Approved Use of Graywater in Santa Barbara County." The County of Santa Barbara Graywater Technical Advisory Committee, March, 1990.

"Grey Water." City of Austin Resource Management Department, 1985.

Carlisle, B.L. and Batte, Charles. Guide to Soil Evaluation and Suitability for On-Site Sewage Disposal Systems for Travis, Williamson, and Hays Counties, Texas . Texas A & M, U.S. Soil Conservation Service and City of Austin, February, 1984.

Brittain, Richard G., DeCook, K. James, Foster, Kennith E., et al. "Summary Reports on Phase I and Phase III, Casa Del Agua: A Community Water Conservation Demonstration and Evaluation Project." University of Arizona, Tuscon, Arizona, July, 1986 and October, 1989.

U.S. EPA. "Onsite Wastewater Treatment Systems Manual." EPA/625/R-00/008, February 2002.

Ludwig, Art. Building Professional's Graywater Guide.
Oasis Design
5 San Marcon Trout Club
Santa Barbara, CA 93105-9726.
A guide to professional installation of graywater systems.