Soon after the floods in Rhodes the Greek Interior Minister, Yannis Michelakis, announced at the parliament that environmentalists are to blame for the floods, as they are opposing the cutting down of reeds in riverbeds. The Minister’s position is possibly misguided since plants and specifically reeds are often used for water run-off management and treatment purposes. So, its adding vegetation rather than removing the existing that will reduce the risk of such flooding happening again in the future.
Large floods have become substantially more frequent globally over the 20th century and climate change scientists warn us that in a warming climate extreme events of heavy downpour will become more frequent, increasing the occurrence and severity of flooding events
This type of flooding is usually more frequent in dry areas or areas of poor permeability. It is usually followed by an extended period of dry weather, or of very wet weather which causes the ground to saturate. In these circumstances the water just runs off the surface of the ground rather than get absorbed. If there isn’t a route for the run-off water to follow, usually by poor drainage or infrastructure planning, the water is randomly directed and floods the nearby areas.
Large floods have become substantially more frequent globally over the 20th century and climate change scientists warn us that in a warming climate extreme events of heavy downpour will become more frequent, increasing the occurrence and severity of flooding events. Average precipitation does not need to change much for flooding to happen. If the same amount of rain falls in more intense but sporadic events the flooding will occur more often.
The most effective way to avoid or minimise the risk of overheating is by avoiding development in flood plains or river beds. For existing developments attention needs to be placed to keep drainage canals and culverts are always clear, create routes for re-directing run-off water, maximise vegetation (plants make the ground more absorptive and their roots retain more water) and maximise the rainwater harvesting (either at building, community or city level).
Sustainable Urban Drainage systems (SUDs) are an approach to managing rainfall that imitates natural drainage. Their techniques of water management are based on the following methods: filter strips and swales, filter drains and permeable surfaces, infiltration devices, and basins, ponds and wetlands. They reduce run-off from the site, use or enhance natural drainage systems e.g. vegetated areas that hold and drain water downhill copying natural drainage patterns, as well as provide additional benefits (creates pleasant environments and encourages biodiversity). Ideally, SUDs should be integrated with rainwater harvesting and wastewater treatment solutions.
We need knowledge before politics.