CBS | Community Based Sanitation

An Overview

Official statistics suggest that about 2.6 billion people do not have access to “improved” sanitation. 75% of these people live in Asia, 18% live in Africa and 5% live in Latin America and the Caribbean.

The Community-Based Sanitation framework, or CBS,  is tailored to improve sanitation conditions in densely populated urban areas. Project implementations depend on the active cooperation of communities, governments, NGOs, and the private sector. Implementation of proven technical options is synthesized with capacity building measures and technical expertise to render CBS an attractive option in areas where neither individual on-site nor centralized sewerage systems can fulfill the need of stakeholders for basic sanitation.


CBS projects take a holistic approach. Instead of simply providing sanitation "hardware", CBS projects aim to improve hygiene behaviour and sanitation infrastructure in a more integrated and sustainable manner. CBS projects generally focus on poor and densely populated areas and closely reflect preferences of target communities.

Half the developing world is still without improved sanitation
The Challenge

Lack of basic sanitation threatens livelihoods and national economies

Increased urbanisation and industrialization has reduced the quality of livelihoods significantly for millions of people who live in low-income settlements within cities. Lack of basic sanitation infrastructure endangers public health and natural resources, coming with both human and financial costs.


Recently published data suggests that improved sanitation reduces diarrhoea morbidity by 32% on average. A report by the Asian Development Bank (ADB) estimates the economic losses through inadequate sanitation and sewage treatment for Indonesia alone to be $4.7 Billion per year. Therefore, in addition to improving livelihoods and the environment, expanded provision of sanitation facilities has the potential to substantially benefit national economies.

Transmission pathways of faecal-oral diseases
Source: Prüss 2002

Causes of death among young children and potential
economic benefit from meeting the sanitation MDG
Source: B. Evans, Securing Sanitation, SIWI 2004

A Demand-Based Solution

New infrastructure development projects usually provide sanitation services to up to 60-70% of the urban population, focusing on those residing in strategic residential areas. In contrast, CBS schemes aim to improve health and environment of communities in densely-populated low-income areas, usually located in inner-city areas or at the fringe of industrialized zones.

The CBS approach fills the significant “gap” between inappropriate on-site sanitation (e.g. absorption pits) and the shortcomings of expensive conventional centralized sewerage collection and treatment systems.

With a CBS scheme, communities find their own informed demand, are given education about the connection between sanitation, hygiene and diseases and are encouraged to organize the operation and maintenance of sanitation infrastructure.

CBS projects are highly demand responsive and rely on active participation as well as contributions from target communities and municipalities. Specific mechanisms have been developed for planning and budgeting in order to make CBS compatible with administrative requirements of governments. According to requirements and abilities, a sanitation solution is planned, designed and constructed for and together with the community.

CBS fills the sanitation gap
CBS Framework and Principles

Successful CBS projects and programs are based on a multi-stake-holder approach: a planning, implementation and management framework in which responsibilities and tasks are shared in a systematic manner between different CBS-stakeholders such as communities, government departments, NGOs, international donors, etc. Two main types of CBS implementation and management schemes can be distinguished:

"Provider-managed CBS Scheme" Up-front investment costs for sanitation infrastructure is financed by public or private development agencies, technical implementation is facilitated by a qualified technical agency (public, private, NGO) and a service provider agency, generally a qualified NGO, is responsible for all operation and maintenance tasks.

"Community-managed CBS Scheme" Investment costs are again financed by public or private development agencies. However, technical implementation relies on the active participation of residents and community organisations are responsible for managing of sanitation facilities.

Both schemes have been successfully demonstrated and are equally valid alternatives. The selection of either scheme should be based on preference of communities and key stakeholders on the municipality level. Within both schemes, contribution of user-fees are essential to cover operation and maintenance costs.


Demand-Responsive Approach (DRA)

CBS initiatives and partnerships are established in regions where stakeholders on different levels are willing to promote, finance and manage CBS infrastructure. Participating communities should be free of conflict between residents.

- Participatory Planning: Participatory project planning must achieve equity within community regarding access to new sanitation infrastructure.
- Informed Choice: Sustainable CBS systems reflect the preferences of stakeholders. Through the Informed Choice approach, communities and municipalities are informed about benefits and disadvantages of different options before decisions are made.
- Professional Design and Workmanship: Functioning and long-lasting sanitation infrastructure depend on professional technical designs and high-quality craftsmanship.
- Operation and Maintenance: Costs for operation and maintenance of sanitation infrastructure should be fully covered by communities/users.

Technical Options - Informed Choice

CBS Components

Selection of CBS-systems and components depends on existing requirements and capacities of implementing communities. Basic CBS system consists of a toilet component, a collection component, a treatment component and a disposal/reuse component. The main CBS-components are shown in the selection-tree below.


Selection Criteria For Technical Options

Capacity: Are components suitable for individual households and/or neighbourhoods with up to 1000 inhabitants?
Costs: Are anticipated investments and costs for operation and maintenance compatible with existing financial resources?
Self-help Compatibility: Can communities effectively assist during construction and implementation? During which phases of implementation are expert staff required?
Operation and Maintenance: Can routine operation and maintenance activities be carried out by members of the community or is expert help required?
Replication Potential: Can local sanitation experts replicate/disseminate preferred technical options independently?
Reliability: Can a problem-free functioning and operation of technical options be guaranteed?
Convenience: How closely do technical options match preferences of communities regarding „convenience"?
Treatment Efficiency: What environmental discharge standards must be met?


Favourite CBS Systems

Analysis of numerous implementations in Asia has shown that three types of water-based CBS systems (or combinations thereof) have been preferred by communities thus far:

Simplified sewerage-systems for settlements
Low-diameter sewerage system that collects and discharges household-wastewater from houses of one settlement into low-maintenance wastewater treatment plants (1)

Shared septic tank system
A number of houses are connected to one septic tank (2).
Systems (1) and (2) are appropriate for smaller and larger poor areas where houses are privately owned and households are willing to invest to upgrade sanitary hardware.

Community Sanitation Centres
Consist of public water points, toilets, bathrooms and laundry areas. Most appropriate in settlements where majority of residents live in rented accommodation and where space is limited for in-house sanitary hardware.

Sludge Stabilization and Treatment Plants

When municipalities want to mainstream CBS and Decentralized Wastewater Treatment Systems

Municipalities embarking on disseminating Community Based Sanitation must be aware of the fact that appropriate disposal of sludges accumulated in small-scale wastewater treatment systems needs to be carried out at intervals of one to two years.

An on-site treatment of digested sludge may be a valuable option in settlements where sufficient area for de-watering or composting is available.

However, municipalities embarking on a large-scale implementation of CBS schemes with integrated small wastewater treatment facilities should consider to plan for installing appropriate sludge-treatment facilities at an early stage of a CBS dissemination programme. This is because an uncontrolled discharge of liquid sludge into the environment poses serious health risks.

CBS Benefits

Improved Livelihoods
Improves quality of livelihoods and health, especially of mothers and children.
Protecting Clean Water Sources
Wastewater treatment options reduce pollution load of groundwater and rivers.
Innovative Potential
Fills the gap between problematic on-site solutions and costly centralized sewerage systems.
Efficiency - Time
Less than 12 months are required for planning and implementing CBS-systems.
Efficiency - Costs
Investment as well as operation and maintenance costs of technical options are low.
Training and capacity building
Stakeholders are trained to plan, implement and manage CBS independently.
Eco-friendly tested technical options
Technical options promoted within CBS are smart, proven, and long lasting. Optional re-use of treated water and biogas utilization are means for active protection of the environment.
Local facilitators ensure future replications in participating cities.
Informed Choice
Communities choose their "own" system after being informed by qualified experts.
High visibility
Regular information campaigns ensure a high visibility of CBS activities in the media.