[Watsan-wg] Blackwater Septic Tank Specs

[Luke LivingStone]

Dear all,


I'm looking for research that clearly defines the minimum containment
volumes of blackwater-only septic tanks vs. numbers of users vs. de-sludging
interval.

So far, the formulas and research papers point to 2-10 year de-sludging
intervals for 1.5 - 2 m3 containment volumes with 5 users.
Yet, I've heard stories of Vietnamese families using their 1m3 - 1.5m3
septic tanks for over 20 years and have never pumped out the sludge and
never added sludge-digesting chemicals.

Could you point me to research which proves there could be very small
blackwater-only septic tank volumes corresponding to long de-sludging
intervals?



Thanks and Kind Regards,

Lucas Livingstone
Program Innovation and Support Manager

"A World Where Everyone Has a Decent Place to Live"  



Habitat for Humanity Vietnam
96/11 Vo Thi Sau, Ward Tan Dinh, District One, 
Ho Chi Minh City, Vietnam
Phone: +84 (0) 8.3820.1566 - Ext. 112
Fax: +84 (0)8. 3820.6133  
Mobile: +84(0) 938.693.748 
Email: luke.livingstone at habitatvietnam.org
Skype: arcticprowler
Visit us at www.habitatvietnam.org <http://www.habitatvietnam.org/> 





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