Urban Sanitation in Developing Countries
November 30, 2021
9th International Workshop on
Decentralized Wastewater Treatment In Asia
Kazushi HASHIMOTO
Adviser, JSC

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There are different types of users & dwellings in urban
areas of developing countries
Type of users

Residentialusers

Non-residential
usersType ofdwellings/
buildings

Affordability
for sanitation
services

Sanitation technology(currently prevailing)

Unplanned
Settlement

Low

Pit Latrine
Septic Tank

PlannedSettlement

Low

Septic Tank
Sewerage System

Institutional
Buildings

Low

Septic Tank

Commercial
Buildings (Old)HighSewerage System
Septic TankCommercial
Buildings (New)High

Sewerage System
High performance decentralized wastewater
treatment systems (DEWATS aerobic type)2

Population living in slums (% in urban population)

World Bank - United Nations Human Settlements Programme ( UN-HABITAT ) (2018)
Region%Sub-Sahara Africa

54

South Asia
(India)38(35)

East Asia & Pacific(China)(Indonesia)(Philippines)(Cambodia)

26
(25)
(31)
(43)
(45)

Latin America & Caribbean

21

Middle East & North Africa

24

Central Europe and the Baltics

5World29(Source) https://data.worldbank.org/indicator/EN.POP.SLUM.UR.ZS
3Affordability to Pay and Willingness to Pay

How much a household must pay for water (water and sanitation)?
Water

Sanitation

Water Total% in householdincome

US$/month/household
Kitakyushu, Japan

22.0

20.6

42.6

1.3

Jakarta, Indonesia

6.9

0.9~2.1

7.9~9.0

1.3~1.5

Manila, Philippines

5.3

1.0

6.3

1.3

Kuala Lumpur, Malaysia

6.5

1.5~1.9

8.0~8.5

0.4

Nairobi, Kenya

8.9

6.7

15.6

Kampala, Uganda

19.7

14.8

34.5

Kigali, Rwanda

12.5

NA

12.5

Lusaka, Zambia

6.3

2.0

8.3

Ouagadougou, Burkina Faso

18.1

2.2

20.3

Abidjan, Cote d’Ivoire

8.9

1.2

10.1

Maputo, Mozambique

9.4

1.4

10.8

(Source: Author [Assumption: water consumption volume20㎥/month/household］)

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Problems and Countermeasures are different depending on the type ofusers/dwellings
Users/Dwellings

IssuesCommercial Buildings (New)

Improvement of monitoring of O/M of high performance (aerobictype) decentralized wastewater treatment plants (DEWATS) (If notconnected to sewerage system)

Commercial Buildings (Old)

Conversion from septic tanks to high performance DEWATS (If notconnected to sewerage system)

Institutional Buildings

Improvement of maintenance
Conversion from septic tanks to high performance DEWATS

Residential users in planned
settlements

Enforcement of regular desludging obligation
Connection to sewerage system

Residential users in
unplanned settlements

Conversion from pit latrine to septic tank
Access to desludging service providers
5Commercial Buildings (New)
Problem

Usually, they are connected tothe sewerage system. If notconnected, even in developing
countries, they use highperformance (aerobic type)
decentralized wastewater
treatment plant (DEWATS).
The problem is that theirperformance is not monitored
properly.

Countermeasure

Strengthening regulation for
onsite system. Japan’s regulatory
frameworks for onsite system (tobe explained later) can be a usefulreference.

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Commercial Buildings (Old)
Problem

Countermeasures

Usually, they are connectedto the sewerage system. If
not connected, some of them
are still using septic tanks.
Conversion from septic tanks
to high performance DEWATS
is slow.

Strengthening regulation for
onsite system. Japan’s regulatory
frameworks for onsite system (tobe explained later) can be a usefulreference.

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Institutional Sanitation (Public offices, schools, hospitals, etc.)
Problem

Countermeasures

If not connected to the seweragesystem, many of them are stillusing septic tanks. Conversion
from septic tanks to highperformance DEWATS is slow.
Their on-site systems (either
septic tanks or high performance
DEWATS) are usually not wellmaintained due to the lack ofbudget and lack of humanresources.

Strengthening regulation on
onsite system. Japan’s regulatory
frameworks for on-site system (tobe explained later) can be a usefulreference.

8Residential users in planned settlements
ProblemCountermeasures

Sometimes, they are notconnected to the seweragesystem, even if there aresewers nearby.
If not connected, they use
septic tanks, which are notregularly deludged, eventhough desludging operators
are ready to do the job.

Strengthening regulation on
sewerage system and on-sitesystem. As for the issue of lack ofregular deludge, Japan’sregulatory frameworks (to beexplained later) can be a usefulreference.

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Residential users in unplanned settlements
Problem

Pit Latrine (particularly,traditional one) is difficult todesludge (it contains a lot of
garbage in it, it will collapse ifhigh pressure vacuum pump isused for desludging).
It is sometimes difficult for
vacuum car to access to thehouses in unplanned settlements.
Desludging charge is too
expensive for the households inslum area.

Countermeasures

Promote conversion from pit latrine
to septic tank (Maputo,Mozambique).
Develop technology for mechanicaldesludging without using vacuum car(Kigali, Rwanda).
Upgrading unplanned settlements
under the World Bank financed
Urban Development Project (Maputo,Kigali).
Increase entry and competition ofdesludging operators by various
economic, social, regulatory
measures (supported by BMGF in
Lusaka, Dakar, Kampala).
10Japan’s regulatory frameworks for onsite system
Problems

Japan’s regulatory frameworks

Improper design of the on-site systems

Structural standards, Government approval, Performance testing systemof the on-site systems

Lack of monitoring of compliance with thebuilding standards of the on- site system

Building confirmation by the building officials of a local government

Poor installation of the on-site systems

Registration system for the On-sire System Construction Vendors
Certification and Examination system for the Installation Workers

Improper disposal of the on-site sludge

Development of the sludge treatment facilities nationwide.

Improper management of the sludge generated
by the on-site systems

Enactment of the On-site System Act (Johkasou Act). Regular desludging
obligation.

Unregulated Desludging Operators working in
the difficult conditions

Approval system of the On-site System Desludging Vendors

Improper operation and maintenance of theon-site systems

Enactment of the On-site System Act (Johkasou Act). Owner’s Legalobligation of O/M. Registration system for the On-site SystemMaintenance Vendors

Lack of human resources for the maintenancework

Training system, Certification and Examination system for the On-site
System Operators

Lack of accountability

Legal inspection

Poor operation and maintenance of the large
size on-site systems of the commercial users

Monitoring under Water Pollution Control Law (compliance to theeffluent standard, measurement ad record obligation, report andinspection)

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For more details;
Please read the following paper.
ADBI Development Case Study No. 2021-1 (June)‘Institutional Frameworks for Onsite Sanitation Management Systems’by Kazushi Hashimoto

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Visual images (what are we talking about CWIS?)(JICA Data Collection Survey on Urban Sanitation, Sewerage and Fecal Sludge Management in Africa)

Central Business District (CBD) andunplanned settlements in Kigali
City, Rwanda

78% of total population lives in
unplanned settlements in Kigali City13

Visual images
Baixa area, a busy downtown area of Maputo
City, Mozambique. Much of wastewater
generated in this area is collected by acombined sewer system and discharged toMaputo Bay without proper treatment.

There are two sewerage system in Maputo
City. But there is no sewerage system in
the northern part of the City which isunplanned settlement where 80% of City
population lives.

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Visual images
Inside of the unplanned settlements inKigai CityThe sludge from pit latrine contains alot of garbage.

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Visual images
Maputo City, Mozambique, is promoting
conversion from pit latrine to septic tankin unplanned settlements where 80% of
Maputo population live.

In Maputo City, private desludging
operators are very active. Daily, 90 vacuum
carloads of on-site sludge is beingtransported to infulene WWTP. But thesystem that makes residents in unplanned
settlements easily accessible to emptying
services seems yet to be established16

Visual images
It takes two hours to remove garbage
before mechanical desludging of pit latrine
starts.

Mechanical desludging without using
vacuum car by PIT VIDURA (a private
operator in Kigali City)17

Visual Images
Concept of the Upgrading of
unplanned settlement under the WorldBank ‘Urban Development Project’ inKigali City, Rwanda

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Thank you for your attention!
Kz-hashimoto@yachiyo-eng.co.jp

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