December 18, 2024

The Planning Institute of Jamaica (PIOJ) is advocating for more widespread use of transformative green infrastructure solutions—a strategy that integrates natural systems into urban spaces—to tackle Kingston’s rising temperatures and urban challenges. Proposed measures include urban forests, green walls, green roofs, detention ponds, and permeable pavements.

Speaking on October 18, 2024 at the recent University of Technology Climate Change Conference, PIOJ Urban and Regional Planner Monique Lewis noted that despite Jamaica’s declining overall population, urban areas are expanding. Over the past decade, the urban population has grown from 54 per cent to 57 per cent. Alongside urbanisation, climate change has brought challenges like heat waves, urban flooding, and prolonged droughts. Jamaica’s climate data predicts record high temperatures, 4 per cent drier periods, and less rainfall. Simultaneously, intense rainfall coupled with unsustainable urban practices has caused severe flooding, resulting in a 1.3 per cent GDP loss in 2023.

Ms Lewis highlighted issues such as the Kingston Metropolitan Area (KMA) traffic congestion. The KMA experiences the “urban heat island effect”, which has limited tree cover, making it significantly warmer than rural areas, and this is exacerbated by heavy traffic. Air quality in the KMA is also closely tied to traffic patterns.

“The data show that air quality in Kingston is in direct relation to the traffic in the area,” she said. “This indicates there is a need for strategies to address both environmental and transportation challenges.”

Strategic climate-resilient urban planning with adequate maintenance budgets is crucial, according to Ms Lewis. “For green infrastructure to be effective, a combination of measures is essential,” she explained, citing studies that show where strategies have reduced air temperatures by 1.5°C and decreased surface runoff by up to 80 per cent, enhancing overall resilience. Ms Lewis pointed to South Korea’s Cheonggyecheon project, which transformed a highway into a man-made stream. The project reduced air pollution by 35 per cent and lowered temperatures by 5°C. For Kingston, she proposed detention ponds and expanded urban forests to mitigate flooding and heat.

She also pointed to the work of the National Environment and Planning Agency (NEPA), which has recommended creating an urban forest in downtown Kingston. This would connect existing parks to increase shade, reduce temperatures, and strengthen environmental resilience. “Street trees from the Waterfront to the St William Grant Park can be extended as far north as National Heroes Circle, creating a green corridor and revitalising Kingston’s public spaces,” she said.

Addressing runoff management, Ms Lewis stressed the impact of current building trends. With the rise of new developments, increasing car parks and other impermeable surfaces worsen runoff issues. Detention ponds, also known as “dry ponds”, offer a solution. These structures hold water during storms while serving dual purposes during dry weather. “Though costly, they have great benefits in creating a ‘sponge city’—an urban area designed to absorb rainwater like a sponge. Detention ponds are recommended for the King’s House area to reduce runoff into Half Way Tree,” Ms Lewis explained.

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