Wetlands are superb at purifying polluted water, replenishing aquifers and harboring wildlife. But they are almost always terrible places to build houses.
Many people have been disregarding regulatory authorities and building homes on wetlands across Harare.
Here are the dangers that could mean you have just wasted your money buying that stand or building that house.
1-When wetlands are filled, the water that made them wet has to go somewhere. If it isn’t seeping back into the basement of the house built on the former wetland, the water likely is leaking into formerly dry homes of downstream property owners.
2- Houses built on wetlands are prone to flooding and collapsing through structural failure, cracking and bending of structures leading to reduced lifespan of the structures.
3- Scientifically, wetlands remove and store greenhouse gases from the earth’s atmosphere, thereby slowing the onset of global warming
Consequently, the building of residential buildings and shopping malls on wetlands are creating a platform for water-borne diseases like typhoid.
4-Wetlands are principally protected by the laws of Zimbabwe and it is illegal to cultivate or build on wetlands before getting approval from EMA.
Section 113 of the Environmental Management Act (Chapter 20:27) states that the Minister may declare any wetland to be an ecologically sensitive area and may impose limitations of development in and around that area.
5- Organic soils, including wetlands, are considered the least suitable for capital construction. This is due to the high moisture saturation of the soil, their looseness, and tendency to deformities.
Thus for one to build on a wetland there is need to use specific types of foundations which can withstand the high moisture content. Thus it’s very expensive.
6- The peculiarity of wetland soils is a tendency to deformation, instability due to a large number of fine-grained particles, high levels of moisture saturation.
During the off-season, such soils are subject to strong heaving and in winter to freezing. The high moisture content in the soil causes the formation of dangerous floats.All this is the reason why soils weakly resist compression.
That doesn’t augur well for you to have your house atop.