With climate change deepening many existing problems African cities face, what can be done to address the crucial issues of water supply and wastewater management? In the capital cities of Ghana and Ethiopia, researchers with the innovative project “URAdapt” are looking for answers.
The people in the impoverished coastal community of Gbegbeyesi, on the outskirts of Ghana’s capital, don’t know why it’s happening, but they see that rainfall patterns are changing and making their lives even more precarious. A few have heard of climate change and wonder if they are feeling its impact.
Dorinda Grant worries about the recent spate of floods in Gbegbeyesi. She runs a kindergarten that, on weekends, doubles as a church in which her husband is the pastor.
The building is just steps away from a drainage canal choked with garbage and human waste. When it rains, she says, the canal floods and filthy water seeps through the walls of the Grants’ church and kindergarten.
“We have no garbage collection here,” she explains. “And people throw it all in the gutter, so we have a problem with flooding.” She says it’s become worse in recent years because of changing weather patterns. In Gbegbeyesi, as in many urban slums across Africa, poor infrastructure makes people particularly vulnerable to climate change.
According to the UN, about 40% of Africa’s 1 billion people now live in urban areas. Of those, about 60% live in slums. Because of the rapid rate of urbanization, services for water supply and waste management cannot keep up with demand. Many urban dwellers have poor access to clean water and drainage and sanitation systems are weak or non-existent. The effects of climate change can only exacerbate these already serious challenges for governments and their citizens.
Accra is no exception. Between 1960 and 2000, the percentage of Ghanaians living in cities leapt from just 23 to nearly 44%. As of 2009, the World Bank estimates that the city’s population had likely exceeded 3.5 million, with an annual growth rate of 4.4%. Already in 2005, close to half the population of Accra lived in slums.
Slum-dwellers coping with acute poverty are highly vulnerable to extreme weather events. Flooding in recent years in Accra has caused deaths, destroyed homes, and increased the risk of malaria and waterborne diseases such as cholera.
Farouk Braimah, Executive Director of People’s Dialogue, a Ghanaian organization that works with the International Slum Dwellers’ Network, notes that when there’s famine or crop failure, rural people flee to urban areas. But this strains already weak urban infrastructure. Braimah says the poor are always the most at risk in urban areas when it comes to climate change — both drought that reduces water supplies, and intense rainfall that brings flooding.
Managing river basins
|Drainage canal, Gbegbeyesi, Accra. To see more photos, visit our flickr slideshow: Adapting to climate change in Accra, Ghana.|
So what can be done to address the current water supply and wastewater management needs in African cities in light of future impact of climate change? What consequences will climate change have on water availability and on wastewater disposal?
These are the key questions that a research team led by the International Water Management Institute (IWMI) is seeking to answer in two African cities — Accra in Ghana and Addis Ababa in Ethiopia. Their three-year project, dubbed URAdapt, is supported through the Climate Change Adaptation in Africa research and capacity development program, which was launched in 2006 by IDRC and the United Kingdom’s Department for International Development.
The URAdapt project looks beyond the urban core in exploring how best to manage precious water resources when factoring in climate change. Project leader Liqa Raschid-Sally of IWMI says the idea is to put the issue of water in cities into the context of river basins. She notes that urban water use cannot be viewed in isolation from other uses and any attempt to make water management practices more climate change resilient must recognise that urban and rural areas often depend on shared water sources for agriculture, domestic and industrial use.
In both Accra and Addis Ababa, some research has been done on urbanization and sustainable water management. URAdapt is now adding the potential impacts of climate change to the research equation. In Ethiopia, it is looking at three reservoirs in the Akaki River basin that serve Addis Ababa and surrounding areas; in Ghana, it is focusing on three river basins that supply water to Accra and carry its wastes — the Volta, Densu, and Odaw.
Predicting changes ahead
Researcher Raymond Kasei is a senior lecturer on hydrology at Ghana’s University for Development Studies. His task is to look at global and regional models on climate change, and then “downscale” them to useful blocks of just 10 by 10 kilometres. In this way URAdapt can zero in on river basins and local communities in and around its target cities, Accra and Addis Ababa.
For Ghana, Kasei looked at datasets from 1961 to 2005, not an easy feat where meteorological data have not been consistently collected over the years. He then ran a model designed by the project to simulate conditions in the Densu River Basin, which supplies water to much of eastern Accra.
From this, he has developed two plausible climate scenarios for key variables such as temperature, rainfall, humidity, and wind-speed. The more likely of the two scenarios, given current trends, predicts that by 2050, the area around the river basins on which urban Accra and rural areas upstream depend will see major changes. The model predicts an increase in average temperature of between 0.5 and 0.8 degrees Celsius, more extreme rainfall events, erratic rainfall during the rainy season, a tripling of extreme drought conditions, and an 8% rise in evapotranspiration.
Preparing for floods and drought
These important early results hold key messages for policymakers, says Kasei. Although flooding has become a major problem in Ghana, his findings suggest that governments also need to prepare for increased droughts. Possible measures could include rainwater collection and storage, better management of water resources, and protection of waterways in both urban and rural areas.
Barnabas Amisigo, a hydrologist and agricultural engineer with Ghana’s Water Research Institute, says URAdapt research has shown, for example, that the Densu River is already reaching water stress levels even without factoring in climate change, while the Volta is not. This, he says, suggests any additional water abstraction for Accra should come from the Volta and not the Densu.
Amisigo says these data will be tailored into tangible recommendations that policymakers and governments can use to design and budget for better water infrastructure – bridges, drains and sanitation, water supply, and irrigation systems.
In Ethiopia, URAdapt coordinator Semu Moges of the University of Addis Ababa and the Addis Ababa Institute of Technology says that early downscaling results show climate change will likely bring increased temperatures and dramatic increases in precipitation during the wet season. “The rural community downstream of the city will feel the pinch as more flooding means more inundation of farmlands with wastewater from Addis,” he says. This finding suggests policymakers will need to revisit the city’s infrastructure and set back distances for communities living near the banks of streams.
Working with policymakers
To ensure that research findings inform and assist policymakers, URAdapt teams in Accra and Addis Ababa have created strong multi-disciplinary Research to Strategic Action Platforms. These bring together a broad spectrum of scientists, engineers and other specialists from local and national government departments and institutions, development organizations and other stakeholders to ensure social needs are taken into account. The platform's sub-committees liaise directly with policymakers.
Lydia Sackey, focal point for the Millennium City Initiative in Accra, is extremely enthusiastic about URAdapt and its importance for the Accra Metropolitan Assembly, where she is budget director. “Any project that examines climate change is important. That’s why at the Accra Metropolitan Assembly, we’ve devoted so many of our officers to this project, including those in public health, in drains and water, in sewage and waste, and even the budget section — we are all part of this Platform.”
Before the project ends in 2012, the Platforms will have developed recommendations in both Accra and Addis Ababa to help local and national governments design their cities and water systems to be resilient in the face of climate change. For the most vulnerable people living in and around the cities, this may prove a matter of life and death.
All photos: IDRC/ Joan Baxter