River floods occur when rivers and streams burst their banks and the water flows elsewhere. This condition usually occurs when heavy rains make normal flow difficult or if channels are blocked at estuary levels. The solutions to address this problem are, among others, the restoration of rivers but also the implementation of embankments.
There are different causes behind the why Italian rivers overflowbut this condition always occurs in the presence of multiple circumstances. The first is any blockages to normal flow at estuary level. The second is bad weather, with heavy rains leading to the breaking of the banks and the water flowing into the adjacent plains.
But river floods bring some variables to take into account, as the responses to meteorological crisis conditions can be different depending on the course in question. In fact, the size and slope of the basin, the speed and capacity of releasing flood waters into the plains are elements that determine different situations.
A storm of a certain intensity and duration of precipitation can cause flooding in one river, but not in another, simply put. But in all cases and not just in Italy, where the hydrogeological risk is high, changes in rainfall patterns, caused in part by climate change, have exacerbated the risk of flooding.
If we want to talk about solutions to the problem, as you can imagine, given the worsening in recent years, reversing the process underlying climate change is an excellent way to return to a natural balance. But on a contextual level, the restoration of rivers and banks is the most suitable way to reduce risk.
Why Italian rivers flood: high hydrogeological risk
Il risk of flooding of rivers is not only the prerogative of Italian territory, but as mentioned by us the hydrogeological risk is high. The data reported by ISPRA, the Higher Institute for Environmental Protection and Research, leaves no room for doubt. Almost 94% of Italian municipalities are at risk of landslides, floods or coastal erosion.
The regions under observation are Emilia Romagna, Lombardy, Tuscany, Veneto, Calabria and Friuli Venezia Giulia, where the conformation of the land and basins is more exposed to flooding. But the entire country is considered fragile from the point of view of hydrogeological disasters, which suggests how important national preventive plans are.
Solutions to flood risk
Nature cannot be contained, nor can environmental disasters be completely avoided, but this does not mean remaining impassive without providing solutions. In fact, any problems can be anticipated, in order to buffer the fury of the water and limit the damage.
Traditional flood defences, in this case, are flood palisades and embankments, which confine water into river channels, preventing it from escaping into more vulnerable areas such as towns and cities. In rural areas, natural embankments can also be restored, allowing normal flow towards the floodplains.
Another method used is dredging, often cited as a key solution to flooding, but widening, deepening or straightening river channels with the aim of moving water downstream more quickly can have few positive effects and is not free from risks.
The classic flood risk management approach is to dam waterways. A result that is achieved, in fact, by building dams and straightening rivers to increase discharge capacity, dredging canals, or building artificial basins and retention areas to store excess water.
But to date it is the so-called restoration of rivers the method considered most effective to limit the risk of flooding and flooding. It is done by reconnecting streams, streams and rivers to floodplains, former meanders and other natural storage areas. A “physiological” way to bring the situation back into balance and reduce the damage.
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Source: www.greenstyle.it
