FEATURE
| JURUTERA January 2014 14
Greywater Reuse: A Sustainable Alternative Water Resource
INTRODUCTION
Sewage generated in a household may be separated into greywater and blackwater discharges. Greywater is FRPPRQO\GH»QHGDVZDVWHZDWHUGLVFKDUJHGIURPODXQGU\
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inhibit seed germination and break down the clay molecules in soil.
QUALITY OF GREYWATER
7KH16:*XLGHOLQHVFRQYHQLHQWO\LGHQWL»HVWZRJUH\ZDWHU streams – bathroom greywater and laundry greywater.
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by Ir. Ellias bin Saidin
Japanese Cascading Toilet Bowl
FEATURE
January 2014 JURUTERA | 15
HOUSEHOLD GREYWATER QUANTITY
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GREYWATER REUSE SYSTEMS
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Parameter Greywatera
Range Mean
Suspended Solids PJ/ ® ®
Turbidity 178 ®! 1$
%2' PJ/ ® ®
1LWULWH PJ/ ® ®
Ammonia PJ/ ® ®
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PJ/ ® ®
Total Phosphorous PJ/ ® ®
Sulphate PJ/ ® ®
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Sodium PJ/ ® ®
Table 1: Typical Composition of Greywater compared with Raw Sewage
a Based on Jeppersen and Solley (1994) NA = Not Applicable
Swimming Pool (2%)
Garden Watering
(47%)
Shower (16%)
Washing Machine (13%)
Toilet (10%) Taps (8%)
Total Other (2%) Leaks (2%)
Source: Western Australia Water Corporation (2002)
Baths and Taps (21%)
Other (5%)
Clothes Washing (13%)
Drinking Water (4%) Washing Up (8%) Outdoor (7%)
Toilet Flushing (30%) Showers
(12%)
Water used in Malaysian home (Source: Bulletin JKR & Alam Sekitar (2006))
Components in greywater drip irrigation system (Source: http://www.platypusenviro.com.au)
FEATURE
| JURUTERA January 2014 16
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STUDIES OF GREYWATER REUSE
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carried out a study which concluded that there was no DSSDUHQW ORQJWHUP HIIHFW RQ ODQGVFDSH LUULJDWLRQ XVLQJ household greywater and that the soil microbes seemed to EHQH»W IURP WKH QXWULHQWV +RZHYHU VXEVXUIDFH LUULJDWLRQ was recommended to reduce pathogenically contamination :(5)
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CONCLUSION
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Mature cotton plants
Photo: Texas A&M University Young tomato plants Photo: Texas A&M University
Household indoor greywater reuse with sub-surface bed irrigation (Source: http://www.greywater.com/samples.htm)
REFERENCES
[1] Art Ludwig (2008), “Builders Greywater Guide”; Published by Oasis Design.
[2] Australian Bureau of Statistics, March 2007.
[3] California, Department of Water Resource (Jan 1995), “Graywater Guide – Using Graywater in Your Home Landscape”.
[4] City of Malibu, Dept of Environment, Building and Safety (1995),
“Greywater Handbooks”; prepared by Peter Warshall and Associates (July 1995).
[5] Draft Guidelines for the Reuse of Greywater in Western Australia.
[6] Heather Kinkade-Levario, (2007), “Design for Water”; New Society Publishers.
[7] Metcalf & Eddy/AECOM (2007), “Water Reuse – Issues, Technologies and Applications”; McGraw Hill.
[8] NSW Government, Department of Water & Energy, “NSW Guidelines for Greywater Reuse in Sewered, Single Household Residential Premises (May2008)”.
[9] Texas A&M El Paso Research Center, WE Jan/Feb 2008; http://
www.werf.org.
[10] UK environment Agency (2008), “Reusing Greywater and Harvesting Rainwater”; www.environment-agency.gov.uk.
[11] UK Environment Agency (2008).“Greywater: An Information Guide”
www.environment-agency.gov.uk.
[12] Val L Little,“Graywater Guidelines”; Published by the Water Conservation Alliance of Southern Arizona (Water CASA).
[13] Venhuizen David, P.E., “Decentralised Reuse with Subsurface Drip Irrigation Fields: Issues and Opportunities”; www.venhuizen-ww.
com.
[14] Water Environment Research Foundation; “Long Term Effects of Landscape Irrigation Using Household Greywater”. www.werf.org.
[15] World Health Organisation: “Guidelines of the Safe Use of Wastewater, Excreta and Greywater”; WHO (2006).
Ir. Ellias bin Saidin is the Advisor, Water Resources Technical Division and he is also IEM Council Member for Session 2013/2014. He is a Principal at Perunding Ikatan.
ANNOUNCEMENT
We are pleased to announce that the
IEM 55th Annual Dinner and Awards Night 2014will be held on
19 April 2014(Saturday) at the Imperial Ballroom, One World Hotel, Bandar Utama, Petaling Jaya.
More details will be announced soon.
Ir. Noor Hisham Yahaya Organising Chairman
IEM Annual Dinner Organising Committee
