With protective greenbelt, Mexican city hopes to fend off climate change

The city of Xalapa, Mexico is bordered by more than 5,300 hectares of mountain forest, a sprawling green sponge that soaks up rainwater and slowly, predictably, releases it to residents downstream.

At least, it used to.

A combination of climate change and deforestation is ravaging Xalapa’s protective tree cover. This is threatening water supplies for around 600,000 people and leaving Xalapa’s bare slopes vulnerable to landslides.

Enter CityAdapt, an initiative led by the United Nations Environment Programme (UNEP) and funded by the Global Environment Facility. It is helping Xalapa’s residents build a protective buffer of plants and trees high in the city’s hills. This defensive shield is being paired with the construction of rainwater harvesting tanks, which are helping residents to contend with a surge in droughts, another byproduct of the climate crisis.

 

“This is the impact of climate change.”

The type of work being done in Xalapa is known as climate change adaptation and was a focus of discussions last month in Panama, where leaders gathered for Latin America and the Caribbean Climate Week. The event was a precursor to the UN Climate Change Conference, also known as COP28, which takes place later this month in the United Arab Emirates.

COP 28 comes with climate change’s impacts accelerating around the world. Government policies now in place could see the world warm by 2.8°C by century’s end, potentially setting off a cascade of extreme weather, including droughts, heatwaves and floods. Developing countries will need to spend up to US$387 billion annually to contend with the fallout, according to UNEP’s Adaptation Gap Report 2023. They now have access to just a fraction of that total.

That is one of the reasons the Xalapa effort, which relies on a combination of low-cost natural and built infrastructure, is considered so important.

The capital of the state of Veracruz, the city gets nearly 38 per cent of its drinking water from the cloud forests that loom above it.

But urban sprawl – Xalapa’s population has grown seven-fold in the last 30 years – is eating away at tree cover, said Angón. Experts say the cloud forest that surrounds Xalapa is one of the most endangered ecosystems in Mexico and is down to 1 per cent of its original coverage.

Since 2017, CityAdapt has been aiming to re-establish the balance between the forest and the city by protecting and restoring ecosystems. 

The project produced an assessment of Xalapa’s vulnerabilities to climate change. That made clear the city’s greenbelt, which includes a hill named Estropajo and the Molinos de San Roque wetland, was vital to filtering water, increasing groundwater supplies and preventing floods.

Project teams, in tandem with local government officials, have worked to revive the greenbelt, sowing more than 6,000 plants, including 3,900 trees. Many of those trees were given to local households, who were taught how to care for them.

“We were delighted to work with UNEP on this project,” said Juan Carlos Contreras, Xalapa’s Secretary of the Environment. “In Xalapa, we are on the front line of the fight against climate change and nature-based solutions play a crucial role in protecting us.”

Recognizing the greenery would take time to pay dividends, CityAdapt also helped build 12 rainwater harvesting systems in schools and public buildings. Designed to counter droughts, the systems provide more than 20,000 residents with a guaranteed supply of water.

Their success led the municipality to install more than 100 other systems, the vast majority in homes, benefitting another 1,200 people.

“Rainwater harvesting systems can be make or break for vulnerable climate-hit communities, and when combined with ecosystem restoration and protection, the results are even stronger,” says Jessica Troni, Head of UNEP’s Climate Change Adaptation Unit.

The Universidad Veracruzana, one of Mexico’s top-ranked schools, teamed with UNEP to build three rainwater harvesting systems. The institution had long battled to provide students with water, sometimes being forced to truck it in.

“During water shortages, Xalapa often only had enough municipal water for a few days per week,” said Laura Bello, who heads up the university’s sustainability group. “We’ve seen just how important low-cost adaptation solutions, like rainwater harvesting, can be for water security in cities.”

Along with Xalapa, CityAdapt is working to support Kingston, Jamaica and San Salvador, El Salvador contend with the climate crisis. By pairing green infrastructure, like forests, with grey infrastructure, like water harvesting tanks, it is aiming to increase the climate resilience of close to 100,000 people.

“With grey infrastructure the benefits can be more immediate, while green infrastructure is more holistic with added benefits, such as promoting biodiversity and urban amenities,” said Troni. “A combined grey-green approach takes the best of both worlds.”

 

The CityAdapt project is officially titled Building Climate Resilience of Urban Systems Through Ecosystem-based Adaptation in Latin America and the Caribbean. For more information on CityAdapt and UNEP’s work with the Global Environment Facility on Climate Change Adaptation, contact Jessica.Troni@un.org