The Ghana Institution of Engineering (GhIE) has called for an urgent overhaul of the country’s stormwater management policies, warning that Ghana’s drainage systems are no longer fit for purpose in the face of rapid urbanisation, climate variability and worsening flood risk.
In a policy brief released, the Institution said conventional drainage infrastructure designed primarily to channel stormwater downstream as quickly as possible has become inadequate for modern urban environments, with Accra and other fast-growing metropolitan areas bearing the brunt.
GhIE said Ghana’s cities can no longer depend on traditional centralised, conveyance-based drainage systems.
Rapid urban expansion, widespread paving over of land, poor waste management, and increasingly intense rainfall have pushed existing drainage networks well beyond their designed capacity.
“Flooding in Accra is no longer simply a seasonal occurrence. It is increasingly becoming a structural challenge driven by rapid urbanisation, loss of natural infiltration areas and fragmented management systems,” the brief states.
The Institution noted that flooding has grown more frequent and severe over the past decade, occurring even during periods of comparatively low rainfall.
It said this pattern points to a problem rooted in systemic weaknesses in stormwater management, not climate change alone.
Blocked drains, fragmented institutions
According to the brief, many of the capital’s drains have effectively become conduits for solid waste, sharply reducing their hydraulic capacity and undermining their intended function. It also singled out the Odaw-Korle drainage system, citing persistent hydraulic constraints that continue to drive recurring flood events across parts of Accra.
Beyond infrastructure, GhIE identified institutional fragmentation as a core obstacle to effective flood management. Responsibility for drainage and flood control is scattered across multiple agencies, the Institution said, while administrative boundaries frequently fail to align with natural drainage basins — a mismatch that makes coordinated, catchment-wide planning difficult to achieve.
To reverse the trend, GhIE is advocating a shift toward decentralised, nature-based stormwater management systems designed to mimic natural hydrological processes. Its recommended interventions include permeable pavements, bioswales and rain gardens, green roofs, detention and infiltration facilities, riparian buffers, and rainwater harvesting systems.
Policy recommendations
The Institution is calling on government to introduce a National Post-Development Runoff Control Policy, which would require new developments to keep runoff volumes and peak flows within pre-development levels.
It is also recommending a National Rainwater Harvesting Policy, stronger enforcement of existing land-use regulations, the creation of catchment-based planning units, protection of waterway buffer zones, and greater private-sector participation in green infrastructure development.
