Dr Juliet Ohemeng-Ntiamoah, a renowned environmental engineer, has sparked a heated debate on the root cause of flooding in Ghana. According to her, silt and sand are the dominant materials blocking drains across the country, not solid waste as many have believed.

On Wednesday, July 8, Dr Ohemeng-Ntiamoah appeared on Joy FM's Super Morning Show, where she argued that the frequent focus on choked gutters caused by waste overlooks the more fundamental causes of flooding. 'I know this can be a little controversial, but I have an article that mentions solid waste is not a major cause of flooding,' she said.

Dr Ohemeng-Ntiamoah attributed the problem to the number of unpaved and unconstructed roads in Ghana's cities, particularly feeder roads connecting major roads. She noted that these roads contribute to dust and sediment accumulation in drains. 'We have a lot of unpaved roads or unconstructed roads, feeder roads joining main roads. Now all that silt, when it rains and the wind blows, carries all that silt and sand into our gutters,' she explained.

She emphasized that authorities' frequent desilting exercises only treat the symptoms and do not address the root cause of the problem. 'When we are desilting the Odaw and all those tunnels, it's mainly sand that we are taking out of that. And how do we prevent or reduce or minimize the amount of silt and sand that choke our gutters?' she asked.

To address the issue, Dr Ohemeng-Ntiamoah called on the government to prioritize the construction of unpaved roads and invest in green infrastructure. She recommended the use of permeable pavements instead of conventional tarred surfaces to improve groundwater infiltration and reduce surface runoff.

Silt Accumulation: The Hidden Enemy

Dr Ohemeng-Ntiamoah explained that the lack of green areas in Accra contributes to stormwater runoff, leading to flooding. 'It's hard to find places in Accra that are well green... the lack of all that is increasing what we call runoff. So when it rains, it doesn't have anywhere to seep into the soil. It runs off quickly... then flooding is occurring.'

She stressed that addressing sediment buildup is crucial to solving Ghana's flooding challenges. 'Our gutters are choked due to silt or sand, and it's as a result of how our cities are planned or unplanned. If we want our gutters or drainage systems to be clean to allow the free flow of rainwater, then we need to address silt. We cannot talk about waste management without addressing silt.'

A Call to Action

Dr Ohemeng-Ntiamoah's comments have sparked a national conversation about the root cause of flooding in Ghana. Her recommendations for the government to prioritize road construction and green infrastructure have been met with both support and skepticism.

As the debate rages on, one thing is clear: Ghana's flooding crisis requires a more nuanced approach that addresses the root cause of the problem – silt accumulation. By prioritizing the construction of unpaved roads and investing in green infrastructure, the government can take a crucial step towards solving the nation's flooding challenges.

Key Facts:

  • Dr Juliet Ohemeng-Ntiamoah is an environmental engineer with over 15 years of experience.
  • The Odaw is one of the main rivers affected by flooding in Accra.
  • Ghana has over 10,000 kilometers of unpaved roads, many of which contribute to dust and sediment accumulation in drains.
  • The government has allocated over Ghc 10 million for desilting exercises in Accra this year.
  • Green infrastructure can reduce stormwater runoff by up to 50%.