Background and the Purpose of
the WEPA International Workshop

Osamu Mizuno
Principal Fellow
Institute for Global Environment Strategies (IGES)

1

Methodology for Domestic Wastewater Treatment
Centralized
Treatment

Cluster
Treatment

On‐siteTreatment

Wastewatercollection andtreatment system for
more than twocommunities(sewerage treatmentplant)

Wastewater collectionand treatment system
for two or morehouseholds but lessthan an entire
community (such ascommunity based
treatment plant)

Treatment system tocollect, treat anddischarge domestic
wastewater fromindividual households
without the use ofcommunity‐wide sewers(such as septic tank,Johkasou)

222

Centralized Treatment Facility in WEPA Partner Countries

Beijing

Kathmandu

Urumqi(1 million m3/day :Activated Sludge)(16 thousands m3/day:Oxidation Ditch)(10 thousands m3/day:Oxidation Ditch)

JakartaSuphan Buri

HCMC

(45 thousands m3/day:Oxidation Pond)(11 thousands m3/day:(30 thousands m3/day:Oxidation Pond)

Stabilization pond)333Service coverage rates of sewerage treatment in
WEPA Partner Countries

Less than 5 %*Chinese data is only for urban area**Except in Sabah and Sawawak province444

Possibility of Decentralized Domestic Wastewater
Treatment in Asia
Centralized
Treatment

Cluster
Treatment

On‐siteTreatment

Wastewatercollection andtreatment system for
more than twocommunities(sewerage treatmentplant)

Wastewater collection
and treatment system
for two or morehouseholds but lessthan an entire
community (such ascommunity based
treatment plant)

Treatment system tocollect, treat anddischarge domestic
wastewater fromindividual households
without the use ofcommunity‐wide sewers(such as septic tank,Johkasou)

555

Diversity in Methodology of Decentralized Domestic
Wastewater Treatment in Asia
Common Facility (There is no toilet and kitchen
in individual households)

Cluster Treatment （各家屋にはトイレ、キッチン等なし）(Common facilitytype)

Cluster Treatment(sewerage type)On‐siteTreatment
オンサイト処理(BlackandGrey（合併浄化槽）Water)

On‐siteTreatment(Black Water)

Examples:
MCK++(Indonesia)

Example:Decentalized
domestic
wastewater
treatment(China)
Example:Johkasou (Japan)

Example:Septic(Thailand)

Tank

666

Past Activities in Domestic Wastewater Treatment
OutputWorkshop in Hanoi

FY2009• Current situation and issues on domestic wastewater
treatment in capital city were shared
Questionnaire Survey

FY2010• Review of national policy for domestic wastewater treatment• Hot spot identification• Collection of good practices on domestic wastewater management (mainlyproject‐level)

Workshop in Manila

FY2011• Good practices (Strategic/programmatic level of experience) on
domestic wastewater treatment were shared at Workshop in Manila

Workshop in Siem Reap

FY2012• Good practices of Decentralized Domestic Wastewater
Treatment in Asia were shared at Workshop in Siem Reap.

777

Pollution Source by Sector in SelectedWEPA Partner Countries

888

SDG 6
From MDGs to SDGs –Addressing unfinished business

Water andsanitation in theSDGs
9

Updated JMP ladders for Drinking Water andSanitation and a New Ladder for Hygiene

101010‐ 58% of urbanhouseholds equipped withseptic tanks‐ > 50% of urban‐‐ 18% of households

households equipped withseptic tanks.
74% of urban population
access to sewer network‐

equipped with onsite
systems (eg. Johkasou)
78% of households
connect to sewer network(Nationwide)‐ 3% of‐ 34% of urbanhouseholds equipped withseptic tanks‐‐ 88% of urban‐ 20% of urbanhouseholds equipped withseptic tanks

households equipped withseptic tanks
56 % of urban households
equipped with other simple
latrines‐‐

4%of septage is
Onlysafely disposed or treated‐ 72% of urban‐ 83% of urban‐households equipped withseptic tanks

households equipped withseptic tanks
It is estimated that 70% ofcollected septage isdisposed of inenvironment‐‐ 10% of septage is‐ 44% of urbanhouseholds equipped withseptic tanks

safely disposed or treated(mainly in Metro Manila)‐ 63% of urbanhouseholds equipped withseptic tanks‐ 10% of urbanhouseholds equipped withseptic tanks
71% of urban households
equipped with othersimple latrines and only
10% access to sewer
network

households
equipped withlatrines
97% of households
connect to sewer
network(Nationwide)‐ 39% of urban‐ 4% of septage is safely
disposed or treatedhouseholds equipped withseptic tanks(Source: WHO and UNICEF, 2017; and database from WEPA website)

111111

Main Objectives of the Workshop
 Understanding about the progress and challenges of addressing the SDG6 in WEPAcountries.
 Roles of decentralized domestic wastewater and septage management in addressingthese challenges and accelerating the progress of SDG6 implementation at the countrylevel Drivers and barriers for implementing DEWATS approach in the region.
 Technology showcase, good practices and innovative business models for DEWATS inthe WEPA countries.
 Facilitating the policy dialogues toward a strategy for regional harmonization oftreatment performance testing methods for DEWATS technologies.

121212