By Nneka Nwogwugwu
Many Nigerians don’t consider the implications of building on areas that are prone to hazards and also don’t seek for professional advice before building construction.
This is evident in areas that end up being swallowed by flood, erosion and by other environmental problems.
In this report, NatureNews in an interview on Monday with a building technologist, Mr. Uchechukwu Awalla, explained the dangers of building on waterways and drainage systems.
A waterway is any navigable body of water. We have maritime shipping routes and waterways used by inland water craft. Dredged channels in the sea are not usually described as waterways.
Awalla while highlighting the impacts of building on waterways on residents and landlords, said that dampness, flooding and Liquefaction are impacts residents will be facing living in such areas.
Explaining further, he said, “The nature of the building and soil location is important in making considerations.
“Dampness causes dilapidation of buildings once there is in and out movement of water in a building. The threat that comes to owners and developers of property whenever rain falls can create sleepless nights fir residents in such circumstances. Those who built on steep grounds and valleys should also be getting ready as the rising Niger River level is getting to a worrisome dimension.
“Dampness could lead to collapse of building and shearing. This means that there will be sheares or cracks on the building due to the weakness of the materials used.
“Liquefaction takes place when loosely packed, water-logged sediments at or near the ground surface lose their strength in response to strong ground shaking. This causes more water to enter the building, thereby make some organic contents to invade the building, which can be harmful to the building.”
He advised that for people to be free from flooding, they must before building the houses, find out if the area suffers often from floods.
“People should be weary of the effect of flood and select grounds where they should put their property because flooding is a major impact for people living in buildings built on waterways.
“People should check if there are dams up, or close to where you are going to build or live. This will drive you to seek expert advice and use appropriate building materials, in flood prone areas and build only in the approved way and in approved areas.
“There is an urgent need for a collaborative effort of both government and stakeholders to support town planning, engineering and other professional agencies to combat flooding in Nigeria to avoid its long-range consequences.
“For every individual, develop your plot with deep or wide drainage system, and don’t dump wastes in the waterways (it’s perilous to you in your living domain,” he added.
Also, in a study by Aquatic ecological specialists published on Planning with Power, the disruption of the natural water cycle leads to a number of changes, including:
• Increased volume and velocity of runoff.
• Increased frequency and severity of flooding.
• Peak (storm) flows many times greater than in natural basins stream form.
• Loss of natural runoff storage.
