As the urban flood season approaches

While determining the land use plan for the city, 100 years flood regime of the streams and valleys on the site earmarked for the city was preserved by the International Plan Associates (IPA). Accordingly, wherever valleys occur such as in the Central Business District, they are recommended to be left in their original natural state. […]

While determining the land use plan for the city, 100 years flood regime of the streams and valleys on the site earmarked for the city was preserved by the International Plan Associates (IPA). Accordingly, wherever valleys occur such as in the Central Business District, they are recommended to be left in their original natural state. Additionally, reasonable buffers between the streams and built-up areas were created. However, despite the comprehensive plan, the city is not free from localised floods in notable spots whenever heavy storms are recorded. The major problem is the violation of these regulations. Often, this results in the loss of innocent lives and immeasurable property destruction.

Flood mitigation literature is replete with many efforts addressing similar challenges. The city resilience programme is a partnership between the World Bank and Global Facility for Disaster Reduction and Recovery (GFDRR). As initiated, it was to build cities with capacity to plan for and mitigate adverse impacts of disasters and climate change, which will enable them to save lives. Best available global knowledge that can create outcomes and impact to help improve disaster risk management were generated and shared.

The City of Boulder located at foothills of the Rocky Mountains in Northern Colorado, learnt to embrace disaster rather than fight it, specifically to prevent the adverse consequences of urban flooding. Water can go from harmless to fatal in no time. In July 1976, the “Big Thompson Flood” occurred. Up to 14 inches of rain fell in a space of four hours and the Big Thompson River Canyon, just a short drive north of Boulder, swelled from 18 inches to 20 feet within minutes. The 31,000 cubic feet of water per second that raced down the canyon took 143 lives, washing some of the bodies 25 miles downstream.

Thirty-seven years later, what was described by the National Weather Service as a 1000 years rain event struck in September 2013. It was a torrential, widespread, days-long rainstorm. The amount of water that dropped was phenomenal. In three days, Boulder County got more rain than it had ever received in an entire month. But flood control efforts by Gibert White, a local resident known as “the father of floodplain management,” helped the county to survive the worst natural disaster in decades. It only left Boulder damaged but not destroyed, and the city bounced back readily. According to David Driskell, Boulder’s executive director for Community Planning and Sustainability, “We’ve been focusing not on large engineering solutions, but more on good land-use planning and stewardship.”

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The takeaway from Gilbert White’s work as further explained by Driskell was, “Don’t put stuff where it shouldn’t be.” You can put it anywhere and then engineer a solution to try to keep it safe. But that is not really the best expenditure of funds and does not really create the kind of quality of life over time that you want to have. Nature has ways of dealing with water. But our actions get in the way of those processes. We just need to move the water through our community as quickly as possible with as little damage as possible.

Recounting the experience, we have similar challenges in many parts of Abuja. Example is the areas along the airport road, running along Lokogoma District and Galadimawa, to areas constituting the Trademore Estate and the other surrounding developments. Due to the surrounding higher grounds, runoff as a result of torrential rainfall increases in speed and volume as it races along the smaller streams with humongous expansion in no time, with high speed to the lower grounds. Unfortunately, the area constitutes a bunch of land use violations with impunity. Loss of lives and property is a constant recurrence; every raining season.

The natural ground has its in-built capacity for the absorption of the rain water through infiltration. This capacity is lost due to surface pavements, hence the astronomical increase in the surface runoffs. The natural solution is, no developments at all in areas constituting natural runways for precipitation. Hence the designations of such areas for green developments only. The wisdom was for the plants to aid absorption thereby minimising runoffs. And in the absence of human residences, no life is threatened in case of any emergency.

It is instructive to note that in almost all the areas where lives and property were lost as a result of floods, developments were made in violations of the rules and regulations. In some instances, some of the culprits with so-called high profile would have the tenacity to take legal actions against the authority, to prevent enforcement. According to Gilbert White, “Floods are acts of God, but flood losses are largely acts of man.” While matters linger in the courts awaiting legal determination, the natural course, with untold consequences, can never be stopped from having its way, nor be delayed.