Connecting cities to basins

Meeting the water and sanitation SDG targets at scale: a focus on Dar es Salaam

Geographic patterns are seen out the window of an airplane traveling between Mwanza and Dar Es Salam, Tanzania on March 20, 2015 (Photo: Brian Sokol/Panos Pictures)

Situated on the east coast of Africa, Dar Es Salaam, Tanzania's primate city, is a thriving commercial centre and regional hub. It is one of the fastest growing cities in Africa. The city-region has a population of 5-5.5 million that could increase more than fivefold by 2050 if it continues expanding at the current rate.

Much of the population growth is the result of internal migration, with young people leaving the countryside to find work in the city. Informal housing is endemic: nearly 80 per cent of the city's inhabitants live in informal settlements.

Delivering sustainable development in this environment is a significant challenge. The Sustainable Development Goals aim to promote the "availability and sustainable management of water and sanitation for all" by 2030.

Despite the global focus of the SDG indicators, decisions around water and sanitation improvements are likely to play out locally, across neighbourhoods, cities, aquifers and basins.

The challenges of providing safe water and sanitation to people living in Dar es Salaam typifies the issues that will be faced by burgeoning cities across Africa and the global South in the next decades.

The Connecting Cities to Basin project sought to connect the river basin and urban water and sanitation agendas in order to consider the challenge of realising SDG 6. Dar es Salaam provides us with a case study to consider the complexity of realising SDG 6 at all levels, from low-income urban settlements to the wider city and, ultimately, the entire river basin.


The Connecting Cities to Basins project sought to:

  • Define community aspirations and trajectories to support water and sanitation improvements that move towards universal coverage in Dar es Salaam in an equitable manner
  • Interrogate the plans and planning assumptions of water utilities to improve water and sanitation provision, based on the water resources available, and
  • Develop a better basis, grounded in local understandings, for IIED to inform and challenge attempts to monitor progress towards international water and sanitation coverage targets.

Drawing on research undertaken with partners in Dar es Salaam over 12 months, the project explored the tensions between international targets and grassroots efforts to achieve universal water and sanitation provision.

It looked at how population growth, rapid urbanisation, and urban planning influence access to water and sanitation, and offered insights around the allocation and use of scarce water resources.

The findings allow us to consider the implications that realising the demands of the urban poor would realistically have for water resources at different scales, and the role that low-income communities can play in improving access to water and sanitation.

A water vending point in an informal settlement in Dar es Salaam (Photo: Anna Walnycki/IIED)

A water vending point in an informal settlement in Dar es Salaam (Photo: Anna Walnycki/IIED)

The tension between global indicators and local progress

In the year 2000, world leaders agreed the eight Millennium Development Goals (MDGs), which were designed to guide development assistance between 2000 and 2015.

Goal 7 focused on environmental sustainability, and included Target 7C, which aimed to "Halve, by 2015, the proportion of the population without sustainable access to safe drinking water and basic sanitation".

To track progress on 7C, the World Health Organisation (WHO) and UNICEF set up a Joint Monitoring Programme (JMP). The JMP introduced indicators for service levels, organised in 'ladders'. The 'rungs' were based mainly on the technical characteristics of the facilities available to households. The water ladder has three 'rungs': unimproved, other improved and piped water. The sanitation ladder has four levels: open defecation, unimproved, shared and improved.

The JMP results showed standards improving over time, but coverage remained persistently lower in rural areas, and in poorer countries and household groups. Overall, Target 7C for the water component was exceeded (91 per cent coverage in 2015, above the intended result of 88 per cent), while sanitation lagged behind (68 per cent in 2015, against a target of 77 per cent). 

However, these statistics and indicators are misleading in several ways.

  • Determining whether households have acceptable access is not simply a matter of deciding which water and sanitation technologies are acceptable. The same facilities may be more or less acceptable depending on where they are being used, for example in rural or urban areas.
  • The phrasing of the targets and indicators implies that "improved" water and sanitation are also expected to be safe, but there were no direct measures of the quality of the water or observation of the final disposal of the faecal sludge. "Improved" provision is therefore not necessarily safe in all situations. Equally, the water target recorded mostly the physical presence of infrastructure (such as a borehole) and not whether it was actually working and delivering water to people on a continual basis.
  • Indicators to track the delivery of the MDG were designed to provide a basis for international comparisons, but this meant that data on locally relevant criteria that could make the indicators more meaningful were overlooked. For example, the narrow focus on households is misleading since, even if an individual household has good sanitation, its health will be affected by the open defecation practised by its unequipped neighbours. Improved sanitation is a local public good that requires a collective response beyond the household.
  • The statistics about the extent of "improved" water and sanitation can also be misleading when it comes to rural-urban comparisons. The implications of using low-cost on-site solutions are very different in rural and urban settings: for example, a shallow well is more likely to be contaminated by leakage from pit latrines in a densely settled urban location, while in rural areas, avoiding pollution from livestock faeces is often a major issue.

In 2015, the world agreed the Sustainable Development Goals (SDGs) for global progress up to 2030. The SDGs include a dedicated goal for water and sanitation, SDG 6, which aims to "ensure availability and sustainable management of water and sanitation for all". SDG 6 contains eight targets, and the draft core indicators currently being developed envisage measuring not "improved" but "safely managed" water and sanitation provision.

As these indicators are finalised, they may incorporate water quality tests and information on faecal sludge treatment and hygiene facilities. If so, estimates of current coverage may need to be revised downwards – to the extent that the ambitious target of universal and safe provision looks completely unrealistic – at least in the absence of a greatly reinvigorated international effort.

At least as important, while these new indicators do potentially provide a better basis for informing local action, they sacrifice local relevance to international comparability and neglect the water and sanitation priorities and practices of local residents.

This is best understood by considering the challenges faced in specific localities, exemplified in this project in Dar es Salaam.

Understanding the issues: from the basin to the settlement

Close to the equator and the warm Indian Ocean, the Dar es Salaam region has a tropical climate, typified by hot and humid weather. During the two rainy seasons the city is frequently hit by flooding.

Surface water supply to Dar es Salaam comes from the Ruvu river (as shown in the map below). The river originates in the Uluguru Mountains, where small streams combine to form three main tributaries, the Mgeta, Ruvu and Ngerengere. The Mgeta and Ruvu drain the south side and the Ngerengere drains the north. 

The gradient of the river reduces as it descends to the lowland areas and the river is characterised by large meanders through lowland floodplains. During the rains, the main river channel regularly breaks its banks. The Ruvu basin experiences a bimodal rainfall pattern with peak rainfall in April/May, a dry season in July/August/September, and a second, smaller peak in December during the short rains. A water offtake downstream of the Morogoro road bridge conveys water to the city.

The region around Dar es Salaam showing the catchment of the Ruvu river

The Mpiji river forms the northern boundary of Dar es Salaam, the Msimbazi river flows to the north of the city centre, and the Kizinga and Mzinga rivers flow into the harbour area of the city. Only Kizinga provides some limited supply to the city.

Water resources and how people access water

The population of Dar es Salaam is around 5 million in the city region. Around half are supplied with piped water while less than 10 per cent have access to piped sewerage.

Dar es Salaam region map showing water supply pattern

Dar es Salaam region map showing water supply pattern

The remainder use on-site sanitation, predominantly pit latrines, which are toilets that collect waste in the ground, in pits that may be lined with various materials. This on-site sanitation sources water from "informal" sources – vendors and/or groundwater – where the quality is affected by pollution from poorly lined pit latrines and saline water intrusion.

Who is responsible for managing water supplies?

The main public agencies responsible for water and sanitation services are the Dar es Salaam Water and Sanitation Authority (DAWASA) and its subsidiary company, the Dar es Salaam Water Supply Company (DAWASCO). They are accountable to the Ministry of Water and Irrigation.

DAWASCO is responsible for the day-to-day operation and maintenance of the water and sewer systems, fee recovery, and providing service connections. DAWASA is the asset holder, building and repairing the major network infrastructure.

The city's wider urban area is administered by five municipalities that maintain public health by, for instance, inspecting pit latrines. They have also constructed monitor boreholes in areas where the DAWASA supply network is lacking.

DAWASA's historical strategy for water supply has been largely based on the exploitation of surface water. Three surface water intakes (two from the Ruvu and one from the Kizinga) feed most of the main public water supply network.

DAWASCO also exploits between 16 and 21 boreholes for public supply. These are not connected to the wider network but distribute supplies to local areas that otherwise lack water. These "emergency" boreholes were drilled in response to the 1997 drought and were intended for short-term usage.

Many more boreholes and shallow wells have been built – either for individual household use or including limited household connections that are often shared with neighbours – and community street taps have been sunk privately in the city. NGOs have also been active in supporting community-managed supplies. Mtoni (2013) noted that while there were only 1,300 registered boreholes in Dar es Salaam in 2005, Baumann et al. (2005) estimated that there were more than 4,000 boreholes in total and, in 2008, Danert put the figure at around 9,000. 

Normally, all boreholes should be authorised and registered with the Wami Ruvu Basin Office (an agency of the Ministry for Water and Irrigation), but not only are total numbers unknown, their offtake from the aquifer is unmonitored.

Informal water and sanitation provision beyond the main DAWASA network is driven by a range of actors including municipalities, NGOs, communities, and a spectrum of private vendors.

How formal and informal urbanisation shapes access to water and sanitation across the city

Key finding

Poor urban planning contributes to the growth of informal settlements and basic service deficiencies, but progressive improvements in access to water and sanitation could be achieved by engaging with the informal water providers in the city

Research undertaken by Ardhi University explored the informal processes of urbanisation that shape unequal access to water and sanitation in the city, and the land development, settlements and basic services that are not planned for or regulated, and are driven by local actors, families, communities and entrepreneurs. University researchers also advocate for better engagement with the informal sector and better collaboration between formal and informal actors in the sector.

"One of the most critical challenges facing the city of Dar es Salaam is how to develop infrastructure for basic service provision, which can in turn stimulate and promote coherent urban growth and development," the university stated. "There are many factors underlying inadequate access to basic services in the city, including the underestimation of the potential inherent to the informal sector.
"Informality is an integral part of urban growth in sub-Saharan cities such as Dar es Salaam. It is a mode of urbanisation that is shaped by local actors, norms and values, at least during the infancy and consolidation of informal settlement development. The practical and strategic significance of urban informality lies in its ability to circumvent the urban planning and design norms. Informality disregards formal regulations and standards to partially meet some of the basic needs of the bulk of urban inhabitants, that the formal land, housing and basic service delivery systems have failed."

Ardhi University argues that, despite its weaknesses, informality will remain a key dimension of urban land development for quite some time in the future; not least because the private sector and the ordinary lower and the middle-income earners are exerting much influence on its sustained growth. Future options to improve services have to be open to engaging with these formal and informal realities in service delivery in the city, and improving the collaboration and mutual interest between the two sectors.

Key finding

Better coordination between formal and informal institutions and stakeholders in the sector could support improvements. This applies to management and governance of water and sanitation services, water sources, and data collection and sharing.

Mapping water and sanitation progress at the community level

Key finding

Local communities have a role to play in identifying water and sanitation needs and solutions. They remain an untapped resource.

The Tanzanian Urban Poor Federation (TUPF) has experience collecting data to improve access to water and sanitation services in informal settlements. In partnership with the Centre for Community Initiatives (CCI), they have profiled and mapped low income and informal settlements

The data is useful for discussing local development needs with local communities, developing local solutions, and then upgrading services both through grassroots approaches and negotiated partnerships with local government and utilities.

Dar storymap

Mapping water and sanitation continued


The maps help low-income communities to highlight the various types of water and sanitation services that exist in their local areas, how they have developed, and how they are used. The map below, for example, shows when and where boreholes have been developed.

A map showing when boreholes were developed in Tungi ward in Da es Salaam

The community mapping team undertook household surveys to better understand decisions made by local people about water and sanitation. The team also carried out water quality testing at utility and non-utility sources and found that water quality was poor throughout.

Sanitation pit emptying practices

On-site sanitation systems don't have sewer pipes to take waste away, so they need regular emptying of pits to enable continued use.

Graph showing sanitation pit emptying practices as per table below


Latrine has never been full72.466.1 81.6
Abandoned and a new one built5.210.910
A truck hired to empty15.56.30
Emptied manually6.916.75
Emptied using a gulper*002
Pit latrine empyting practices across three communities
*A "gulper" is a small mechanical pump used to empty pit latrines that are hard to reach with trucks

The statement that the latrine "has never been full" is somewhat unlikely given the age and size of households. Tenants might not be aware of how pits are emptied and/or landlords may not wish to admit to rainy season flushing of pits that are full.

The importance of understanding community perceptions of progress

CCI used the findings from the household surveys and mapping activities to begin community discussions about what constitutes "unacceptable", "acceptable" and "ideal" water and sanitation provision.

The communities also discussed the Joint Monitoring Programme (JMP) ladders. They found the global indicators didn't adequately reflect local realities because there is so much variation in the types of water and sanitation in low-income urban communities, and instead came to focus on a series of features and their acceptability.

Representatives from each of the three communities then came together to develop a ladder that would be useful for low-income and informal communities across the city of Dar es Salaam that do not have access to water and sanitation. Certain categories were combined and edited to simplify the ladders.

These outputs show the potential for using JMP ladders to reflect and support improvements in services in low-income and informal settlements.


ExamplesiconUnlined and poorly lined pit-latrines (using barrels, tyres etc.) Soak-away pit/pit latrine with asian squatting pan, which does not transmit diseasesSewer connections (including simplifed)/septic tank/vacuum tank emptying
EnvironmenticonWastewater flows to immediate environmentNo impact on immediate environmentToilet is well constructed; wastewater does not flow to neighbours, or contaminate environment/groundwater sources
CleanlinessiconFull pit, causes back flow, dirty toilet, poor ventilation, damp, fungus and mouldClean inside and easy to keep cleanCleanable floor and tiles, with tools and products available for cleaning; hand washing facility
StructureiconUses cloth, sacks, tree branches etc.Needs a roof, walls and door; lined with bricks or blocks, slab with durable woodBrick construction, well built, with opening for ventilation, door for privacy
Waste removaliconManual emptying; opening and flooding of pit during the rainy season; abandoning pitsSafe emptying without polluting the environment; no manual emptyingWaste removal safe, affordable and appropriate to local context – e.g. sewers, simplified sewerage or vacuum tankers
SharingiconMore than five families sharing2-4 households sharing; 8-20 peopleNo more than one family or 5-6 people sharing
CosticonUsually more than TSh2 million (excessive cost); lower than TSh400,000 indicates poor quality toiletFor households to build new toilet: TSh1–1.5 million (high cost due to need to dig pit and buy tank)For households to build new toilet: TSh600,000-800,000
Water for sanitationiconMen should use between 20 and 5l; women between 30 and 10lWater needed, same as for ideal (20–30l)Men approximately 20l; women 20–30l
PrivacyiconNo door, no privacyLockable doorMen: toilet can be inside or outside of house but tank/pit should be outside; women: inside toilet preferred unless plot is fenced
Tsh500,000 = US $225 (January 2017)


Proximity to house/usericonMore than 30 minutesNo more than 5 minutes from the houseIdeally, taps in kitchen and bathroom (particularly important for women); at least tap at yard level
Time to collecticonDaily water collection takes 1.5-2 hoursNot more than 15 minutes to collect daily waterNegligible as in house/yard
TreatediconNot treatedTreated to water utility standardsTreated to the level of the water utility (for cooking and drinking, might boil)
TestediconNot testedTested to water utility standardsTested to water utility standards
Costicon1 bucket for TSh300; more than TSh30,000 monthly per house; more than TSh10,000 monthly per householdHousehold connection no more than TSh350,000; affordable monthly cost per house TSh15,000-30,000 (TSh7,000-10,000 per household)TSh200,000–250,000 to get household connection; TSh15,000-20,000 monthly per house with multiple households sharing (TSh3,000-4,000 monthly per household); some prefer metered, others flat rate
ReliabilityiconFrequent rationing (up to twice a week)Water available 6-12 hours per day; morning and evening availability important1 bucket for TSh300; more than TSh30,000 monthly per house; more than TSh10,000 monthly per household
SourceiconShallow untreated well; piped network through drainage channels; borehole near toiletsDar es Salaam Water and Sewerage Corporation, wells, boreholes (if treated and tested); accessing multiple sources for different uses acceptable; people prepared to walk further/take more time to collect drinking waterUtility water ideal, but also deep boreholes  
StorageiconNone or near toiletsYesStorage of approximately 100l for emergency situations, e.g. power cut
QuantityiconLess than 15l per person per day; water for sanitation is additional60l for small family; 110l for large family (15–20l per person per day); water for sanitation is additional80–100l per HH per day (20–30l of water per person per day); water for sanitation is additional

These ladders provide a more nuanced understanding of what progress looks like from the perspective of communities. For example, although the JMP suggests that no more than two households should share a toilet, the tendency towards compound living with multiple households in Dar es Salaam means that community members would find it acceptable for more people to share a toilet than suggested.

Further discussions around water suggested that around 50 litres of water per person per day would be acceptable, for water and sanitation.

Local ladders fuel discussion

Community members suggested that local ladders were valuable because they present improvements that are under the control of the household or community (such as a door with a lock), and distinguish these from improvements that can only be brought by the state or utility (such as wastewater removal).

The ladders fuelled discussions about how a household or a community moves towards "acceptable" or "ideal" water and sanitation provision, and the associated roles and responsibilities of the utility and the state.

One participant said that this ladder allows them to consider "who is not doing their job properly", and community members made a number of suggestions, including that:

  • Households should take responsibility for sanitation at household level and make the connection to infrastructure if made available and the cost is affordable
  • Households should be aware of the sort of pit latrines used, and how wastewater is stored. Improvements to water and sanitation facilities could focus on certain features identified in the ladders, such as privacy or cleanliness.
  • "The community should be organised and self-aware" – and ready to respond to water and sanitation programmes initiated by the state and utility.
  • Communities might also identify which improvements require collective action at the local level, such as simplified sewers.
  • "The utility has to bring the water and sanitation" – the discussion made clear that main infrastructure to bring water in and take wastewater out of communities is the responsibility of the utility, and that this includes project supervision, maintenance and repair. It also means that the utility has the responsibility to defend and protect water sources. Although households and communities can undertake some upgrading, improvements in water and sanitation provision can only be realised with inputs from the utility
  • Community members agreed that improvements to all sorts of basic services could be made by building bridges from "the sub-ward, to the ward level, then the municipal. Local leaders can exert pressure and be creative around funds, and local development plans". This builds on the overarching approach that characterises federations of the urban poor: that incremental development can best be achieved when low-income communities work together with government to find solutions.
Community members meet to discuss local ladders (Photo: Anna Walnycki/IIED)

Community members meet to discuss local ladders (Photo: Anna Walnycki/IIED)

The wider picture: water resources for Dar es Salaam

Key finding

The Ruvu river will experience occasional dry season shortages which are not being planned for and which will have implications for Dar es Salaam.

The most important water source for Dar es Salaam is the Ruvu river. DAWASA's intakes and pipelines from the Ruvu have recently been upgraded and are taking close to the maximum that can be removed from the river when it is at its lowest during the dry season. As a result, the Ruvu is expected to be able to provide for the planned flows up to 2030 to Dar es Salaam for more than 90 per cent of the time; however in some dry periods, river flow is likely to be insufficient.

At such times the only alternative water source for many consumers, including low-income communities, is the shallow aquifer that is already being exploited by boreholes in many of Dar's informal settlements.

The outlook for aquifers

The Kimbiji aquifer, which is situated along the coast to the south of Dar es Salaam, had been expected to provide a significant alternative water resource, with enough water to cover the city's requirements well into the 21st century.

But recent assessments suggest that the maximum sustainable yield from this resource is much smaller than previously thought, and therefore may not, on its own, meet the future demand levels projected by DAWASA.

What's more, the situation is expected to worsen as a result of more irrigation permits being issued to farmers in the upstream catchment areas.

Our best estimates suggest that by 2030 the city may be 300,000 cubic meters per day (m3/d) short of the water demands projected by DAWASA. This equates to around 10 per cent of Dar es Salaam's needs.

Water abstraction from the coastal aquifer is unsustainable. Outflows currently exceed inflows (m3/sec)

Water abstraction from the coastal aquifer is unsustainable. Outflows currently exceed inflows (m3/sec)

A second aquifer, the Dar es Salaam Quaternary Coastal Aquifer (DQCA), currently provides for large parts of the city through thousands of private and community boreholes. But various strands of evidence show that this aquifer is under severe stress, subject to declining water levels, saline intrusion and pollution from the urban environment, including leaks from poorly lined pit latrines.

Key finding

The use of the Dar es Salaam Quaternary Coastal Aquifer is currently unsustainable.

Its current and future role as a water resource will require careful management as well as engagement with the informal sector. Controlling abstraction and implementing an appropriate management approach could counteract the imminent risk of losing the resource. This could also enhance the resilience of the city's water supply at future times of stress.

Modelling the future

As part of this examination of Dar es Salaam, we conducted a modelling exercise to look at how water availability compared to extraction plans up to 2032.

The results of the modelling exercise, using existing data provided by the Wami Ruvu Basin Office, suggested that there is insufficient water in the Ruvu river in the dry season to meet DAWASA's calculated abstraction requirements with a 100 per cent guarantee. After 2032, supplies will fall short between seven and 18 days per year, on average. Supply deficiencies cannot be overcome by simply increasing water extraction from existing groundwater and surface water resources.

The water deficits identified could be reduced somewhat if water losses were cut; groundwater resources were managed sustainably; and the consumption of those using more than 50 litres per day was reduced through demand-side management measures (such as pricing policy). This is the figure identified by CCI, TUPFI and community members as being an acceptable level of water allocation per person for drinking and sanitation.

In the absence of major improvements in water management, however, there are likely to be shortages. And given past experiences, these shortages are likely to amplify the other challenges to universal provision. Moreover, the assumptions underlying the DAWASA planning model may be overly optimistic – for example, population growth rates could be higher than anticipated, and there could be serious droughts.

Lessons from Dar es Salaam for meeting SDG 6 at scale

Over 12 months the Cities and Basins research sought to identify some of the key water resource and urban planning challenges to realising SDG 6 from the settlement to the basin level. In our concluding meeting in Dar es Salaam in November 2016, we identified the following key lessons to shape our future research agenda.

Key finding

Poor urban planning leads to informal settlements and basic service deficiencies, but progressive improvements in access to water and sanitation could be achieved if the government engages effectively with communities and the informal sector.

  • The maps and ladders produced at the community level reveal the complexity of water and sanitation provision, the local priorities of communities, and the incremental nature of progress that is not captured by global indicators. Federations of the urban poor can use this data to secure funding and develop strategic relationships with sector stakeholders for incremental improvements to water and sanitation services. Such efforts complement or offer intermediate solutions during the long term expansion of utility water and sanitation infrastructure.
  • There is a need for new sanitation technologies that can deliver in densely populated areas and/or support (political and resource) to scale up water and sanitation solutions for low income settlements.
  • Dar es Salaam lies within an increasingly water scarce catchment. As competition for water increases, particularly with upstream farmers, water managers must adopt a flexible and adaptive approach based on better knowledge of the available resources and their fluctuations with rainfall and climate change
Key finding

The Ruvu river will experience shortages which are not being planned for and which will have implications for Dar es Salaam.

  • Groundwater use in the city is largely unregulated, and there are significant concerns about depletion and contamination. Despite the fact that the DQCA is a key water source for many low income communities, it does not feature in government plans as a source that could help meet the water needs of the city during dry years, nor is it effectively monitored. 
  • Accurate, consistent and timely data on water resources is vital. Investing in long term, structured data collection and monitoring is essential to develop the database required for effective decision making. Planned improvements would also benefit from more collaboration, data and knowledge sharing between formal and informal actors and institutions involved in water and sanitation provision in the city and basin. DAWASA, the local municipalities and the Wami Ruvu Basin Board need to operate as a seamless unit in delivering clean water for everyone.
  • The current study has assumed similar trend of water flows in the future, but the impact of climate change on river flows requires further consideration.

These findings have clear implications for Dar es Salaam and the Sustainable Development Goal ambitions to move towards universal access.