As the world strives to tackle climate change and build resilience to prepare communities for its destructive effects, nature-based solutions are being seen as a panacea. panacea. These projects, which leverage nature and natural processes to help reduce the effects of climate change and harmful human activity, are increasing in number and scale.
In the Philippines and India, mangroves are being expanded to combine with existing breakwaters on the coast to provide protection from storms and floods. Likewise, in South Africa, wetlands are being restored to replenish groundwater and protect water-insecure cities from drought, such as Cape Town.
Communities around the globe are encouraged to scale nature-based solutions and integrate them into modern infrastructure. one year 2021 report published by the International Institute for Sustainable Development (IISD) concluded that such an approach could save the world $248 billion annually in construction costs to expand infrastructure.
Governments around the world are investing in research and development of nature-based solutions, while global financial institutions such as the World Bank are actively involved in funding projects using nature. use such methods.
As urban planning scholars studying water, urbanization and climate equity in small and medium-sized cities in South Asia, we agree that nature-based solutions hold promise. . But we also recommend caution. Our work in Khulna, an area in southern Bangladesh facing multiple ecological crises, provides an example of how integrating nature-based solutions can lead to positive outcomes. complexity helps some communities while harming others.
Khulna’s ‘Nature Based Solution’
In 2011, Khulna, Bangladesh’s third largest city, was facing severe water scarcity. Along with groundwater depletion and pollution, salt water is increasingly entering freshwater sources. Local governments had several options to deal with the crisis.
It could build a desalination plant to treat water from nearby rivers. But such installations are known to be ecologically harmful. For example, an article by the Canada-based Institute of Water, Environment and Health notes that desalination plants release 142 million cubic meters of ultra-salty brine per day globally. That’s enough to cover the US state of Florida under 30 centimeters (12 inches) of salt water, which can be toxic and extremely harmful to marine life.
Another option offered by local governments is to implement stricter water controls on residents and businesses. This means asking residents to conserve water and industries to ditch water-intensive activities and invest in rainwater harvesting systems. Such water conservation policies can be difficult to implement and politically unpopular.
To avoid the negative effects of the desalination plant and potentially unpopular water conservation policies, the local government chose to build a “climate-resistant” water supply system that they manage. to obtain foreign funding from the Asian Development Bank and the Japan International Cooperation Agency (JICA).
This water supply system is planned to take water from the Madhumati River in the village of Mollahat, 40 kilometers northeast of Khulna, and bring it into the city. During the rainy season, the water will be treated directly by the water treatment plant and then supplied to the consumer. During the dry season, when the salinity of Madhumati is high, the water will be mixed with low salt water taken in the reservoir during the rainy season to reduce the salt concentration before being sent to the plant.
Policymakers hope this “nature-based water mixing solution” will solve future problems as sea level rise will further increase the salinity in Khulna’s water. Framing the new water infrastructure as climate- and nature-friendly has allowed local governments to justify costly project construction.
The new water supply infrastructure, completed in 2019, really benefits Khulna residents. It increase Access to tap water increased from 23 percent of households to 65 percent and provided access to water for some informal settlements that were previously unavailable.
The problem the ‘solution’ creates
The popularity of the new water system in Khulna was evident in the interviews we conducted with city dwellers. They report that women can now get water from the tap at designated times instead of having to queue for hours to get water from a pipe well.
The reports from Mollahat, however, are quite different. During our fieldwork in 2018, one of us spoke to a local, Mohammad Liton, who said he barely slept during that year. Liton overcame worries about rising salinity and low water levels in the Madhumati River, which had already begun to affect his livelihood. Liton argues that the Khulna water project has reduced the availability of water for fishing and rice farming in the Mollahat area.
In January 2017, Liton and other residents of Mollahat organized a protest against the project that was affecting the lives of thousands of farmers and fishermen living in the village, but the authorities did not address the issue. their concerns.
The project’s environmental impact statement, at the request of the Bangladesh government and foreign donors and completed in 2011, focuses primarily on the water supply sector and considers construction as a sole action against Mollahat.
According to a representative of the Bangladesh Environmental Lawyers Association (BELA) we interviewed, the scale of assessment incorrectly calculated that the Madhumati watershed only existed in Bangladesh. The river is a tributary of the complex Ganges river system, with its flows coming from the Ganges in neighboring India.
The Madhumati River has been hit hard by the controversial construction of the Farakka Dam upstream in the Indian state of West Bengal, which diverts its water. The dam has made the river basin much more time and ecologically sensitive, so the additional burden of fetching water for the Khulna project has significantly strained the river’s resources and affects Mollahat and other communities along its basin.
Approach nature-based solutions with caution
Khulna’s water project should be a cautionary tale – one that can teach policymakers lessons about what they should and shouldn’t do when implementing nature-based solutions.
In this case, while Khulna’s industries and households benefit from the projects, the residents of Mollahat bear the costs. This could have been avoided if the local government had consulted with villagers at the construction site and downstream while assessing the project’s impact. Their feedback could have been used to tweak the implementation.
Local government should also aim to distribute benefits equitably between city dwellers and neighboring rural communities. For example, they could ask industries to conserve water, which would relieve pressure on the Madhumati River and significantly reduce the impact on the Mollahat community.
When green approaches are combined with infrastructure, local governments must ensure that no harm is done to neighboring communities. Fixing a city’s water problem shouldn’t come at the expense of rural communities.
As nature-based solutions are scaled up, we urge policymakers, donors and communities to be more vigilant. Infrastructure projects, like the one in Khulna, must minimize harmful impacts and help address inequalities at the local and regional levels.
The views expressed in this article are those of the authors and do not necessarily reflect the editorial stance of Al Jazeera.