This is the latest post in Human Nature’s “Urban Jungle” blog series, which explores the inextricable connections between intact ecosystems and thriving cities.
During 2010 and 2011, millions of Colombians were in the rain.
Throughout many months that saw little relief from the downpour, urban areas of Bogotá and several rural areas of the department of Cundinamarca experienced very severe flooding as rivers spilled over their banks, flooding a nearby university and destroying agricultural fields.
Other areas on the slopes of the northern Andes saw a lot of landslides, causing not only significant losses in human life, but also economic costs like crop failure and infrastructure collapse.
To some degree, these extreme weather events are the result of La Niña, which causes a significant increase in water flowing through the mountains, exceeding the capacity of these degraded landscapes to filter and absorb it. This situation contrasts with El Niño, a period characterized by a significant reduction of water supply and high vulnerability to forest fires and droughts.
But there is also another force at play — one which shows no sign of slowing down. According to the Intergovernmental Panel on Climate Change’s (IPCC) 2012 report, overall temperatures in Colombia are predicted to increase, with up to 60% growth in rainfall during La Niña and declines of 60% in periods of El Niño.
In addition, population growth in Bogotá — already one of Latin America’s largest cities, with more than 8 million residents — is expected to continue, exacerbating current strains on the supply of fresh water and other resources.
Most of the water consumed in Bogotá comes from high mountain forests and páramos located in Chingaza National Park and its buffer zones. Therefore, it’s important to concentrate most conservation and restoration actions in those ecosystems in order to guarantee a permanent water supply to the city.
In response to these worrying trends, in 2013 CI conducted a vulnerability assessment that would determine the level of threat climate change poses to the “Sabana de Bogotá,” the high plateau region surrounding the country’s capital. Our effort was supported by the Colombian government, the U.N. Development Programme and other partner organizations.
We focused our assessment on answering two main questions:
- How will climate change impact freshwater availability for people in and around Bogotá?
- Which areas in the region are the most — and least — capable of adapting to these changes?
The vulnerability assessment was carried out using an “ecosystem-based approach,” aimed at assessing the impacts of climate change on key hydrological services that affect the amount of water available to the population for needs like drinking and cooking, hygiene, hydropower and agriculture.
To conduct this study, we compiled a range of data from a variety of sources — including hydroclimatic conditions, socioeconomics, poverty rates, population growth and distribution, housing quality and access to public services, soil quality, presence of protected areas and resource management plans, as well as current environmental threats that pose risks to people.
Data was supplied by Colombia’s Institute of Hydrology, Meteorology and Environmental Studies and other national and regional organizations. We then used eco-hydrological modeling tools like Water World and Co$ting Nature to make maps illustrating what we learned.
Our analysis indicates that most of the territory has a moderate capacity to respond to climate change impacts. There are some municipalities and areas of Bogotá, however, which have less of a chance — unless we help them.
Here are some of our findings — and some of the solutions that could help fight the predicted impacts.
- Less water available across the Sabana de Bogotá, some western municipalities and especially some catchments that supply water to the capital and other urban areas. Proposed adaptation actions include water efficiency programs, restoration of high mountain ecosystems, development of alternative sources of water gathering, development of more efficient infrastructure for dry periods and monitoring and early-warning systems for heavy rains and droughts, as well as various programs through which people make direct payments for their use of natural resources and the benefits that ecosystems provide.
- More flooding along main rivers, affecting urban and rural human settlements, agriculture and local industries. In addition, flooding could bring high risk of landslides on deforested slopes, affecting many agricultural areas and rural settlements. Adaptation responses include: wetland protection and restoration; conservation of high mountain ecosystems; sustainable use of conventional engineering, such as drainage, maintenance of canals and watercourses; construction of small dams; and relocation of families living in the most vulnerable areas.
- More forest fires due to droughts, especially in some municipalities located in the northern and western part of the Sabana de Bogota. For these areas, the removal of invasive species and restoration with fire-resistant species has been proposed.
- Decline in water quality due to sedimentation, affecting water management facilities west of Bogotá, and in the western Andes. In these locations, actions such as ecosystem restoration, slope stabilization and domestic waste treatment initiatives could help improve water quality.
- Changes in distribution patterns of sensitive species, such as endemic, threatened and migratory species occurring in Andean forests, wetlands and swamps of the Sabana de Bogotá. Response actions include the design of wildlife corridors in agricultural and urban landscapes and the management of invasive species.
The department of Cundinamarca and the capital district have officially adopted this study’s findings, and the Colombian government will share them with the U.N. Framework Convention on Climate Change.
Moreover, its results will be the basis for the new four-year Global Environment Facility climate adaptation project, which CI Colombia will be implementing soon in the Chingaza-Sumapaz-Guerrero area. CI also recently made a Clinton Global Initiative commitment to facilitate an information exchange between Bogotá, Mexico City and Rio de Janeiro — three cities facing similar concerns about freshwater access due to ecosystem degradation. (Learn more about how Bogotá’s páramo ecosystems provide water in our award-winning film below.)
This is a groundbreaking study for Colombia, as it proposes new ways of understanding local vulnerability to climate change. Because fresh water is tightly linked to food and energy production, its availability — or lack thereof — cannot be treated as an isolated issue. Instead, we must take a holistic approach that seeks to fight all these challenges at once and ensure that Bogotá’s future will be a prosperous one.
Angela Andrade is the environmental policy director for CI Colombia. Patricia Bejarano and Andrés Páez from CI Colombia and Leonardo Sáenz from the Moore Center for Science and Oceans also took part in this study. Learn more about climate change adaptation in Colombia.