Nakuru County is embracing the “sponge city” concept to combat the adverse effects of climate-change and help promote sustainable social, economic, and water climate resilience to accelerate climate change adaptation.
County Executive Committee Member (CECM) for Water, Environment, Energy, Climate Change, and Natural Resources, Dr Nelson Maara said the sponge cities concept would enable them use what the city already has such as parks, lakes and rivers to reduce climate change risks by offering a potential solution to control the damage caused by the risks including floods, droughts, land sinks among others.
According to Dr Maara, despite the presence of emergency response teams like the National Disaster Management Unit (NDMU), there was a growing need for proactive measures to be put in place to prevent disasters.
Dr. Maara cited the rapid spike in population, unplanned urbanization, climate change, uncontrolled land-filling to develop new residential areas, haphazard disposal of waste into the existing drainage system, and encroachment of lakes, canals, and rivers as some of the major contributors of Nakuru County being prone to flash floods.
The CECM however assured that Governor Susan Kihika’s administration was now embracing the “sponge city” concept, which he said integrates green infrastructure such as parks, rooftops, and urban forests to absorb rainwater while revitalizing blue infrastructure like rivers and wetlands to improve storm water management and biodiversity.
He explained that a sponge city is one that is built to passively absorb, clean, and use rainfall in an environmentally friendly manner, reducing pollution and hazardous run-off.
Sponge cities, Maara added, rely on natural resources such as lakes, rivers, grass, and soil to create absorbent ground surfaces that allow rainwater to be stored.
“A city’s ability to absorb water referred to as its “sponginess” is one key to withstanding climate shocks, with sponginess dependent on the amount of greenery and other water storage available,” the CECM explained.
While making a presentation during a workshop at a Nakuru hotel themed “Role of Sponge Cities in sustainable urban development,” Dr. Maara said the County Government was working on Sponge City initiative in partnership with Water as Leverage (WaL) partners, UN-Habitat, the Netherlands Enterprise Agency and Vitens Evides International (VEI).
Nakuru City Manager Gitau Thabanja highlighted the importance of partnerships between governments, local communities, and the private sector in achieving financially viable and long-term solutions to natural disasters.
The manager explained that Nakuru’s sponge city program aimed at using porous pavements, rain gardens, green roofs, urban wetlands, and other innovations to absorb water during storms after which the soil purifies that water and gradually releases it much like a sponge.
“Green spaces set aside in sponge city’s design absorb carbon dioxide and consequently contribute to a lower amount of the greenhouse gas in the atmosphere,” added Thabanja.
Last year the County Government signed a memorandum of understanding with Netherlands towards enabling Nakuru adopt the Sponge City concept under the Water as Leverage (WaL) program, an initiative said to make the city withstand variable temperatures, drought and heavy rainfall.
Thabanja explained that WaL Program was an initiative of the government of the Netherlands that promotes sustainable social, economic, and water climate resilience to accelerate climate change adaptation.
The programme is said to be committed to develop innovative, climate-resilient water-related infrastructure solutions for Nakuru that will contribute to addressing urgent water and climate adaptation needs.
WaL Program sponge city concept is said to promote a more harmonious relationship between humans and nature that in effect gives water more room to soak in and pool in urban areas – such as parks that are dry in some seasons and become shallow ponds or channels in rainy seasons.
The sponge City concept was first introduced in China in the early 2000 to address surface-level flooding in urban areas. In 2014, pilot projects were initiated in several Chinese cities.
As climate change leads to more extreme weather events like heavy rainfall and droughts, it has become crucial to integrate floodwater management systems in cities.
The World Meteorological Organization reported that around 44 per cent of global weather-related disasters in August 2023 were linked to flooding.
This finding highlights the growing global phenomenon of flooding and the urgent need for preventive measures.
The World Economic Forum (WEF) found that ‘nature-based solutions to climate change’ were up to 50 per cent more cost-effective than engineered alternatives.
By Esther Mwangi