Tulvasuojana

Tulvasuojana is a Finnish term that translates to flood protection or flood defense. It refers to measures and structures implemented to prevent or mitigate damage caused by floods. These measures can be broadly categorized into hard engineering solutions and soft engineering solutions.

Hard engineering solutions typically involve constructing physical barriers. Examples include building dikes, levees, flood walls, and dams. These structures are designed to hold back floodwaters and prevent them from inundating populated areas or valuable infrastructure. In some cases, reservoirs and retention basins are also used to temporarily store excess water during periods of high rainfall or snowmelt, releasing it gradually to reduce downstream flood risk. Pumping stations may also be employed to remove water from areas that have been flooded or are at risk of inundation.

Soft engineering solutions, on the other hand, work with natural processes to manage floodwaters. This can include restoring or creating wetlands and floodplains, which act as natural sponges, absorbing and storing floodwater. Reforestation and afforestation in upstream areas can also help by increasing the land's capacity to absorb rainfall and reducing runoff. Permeable surfaces in urban areas, such as porous pavements, allow rainwater to infiltrate the ground rather than contributing to surface runoff. Managed realignment of coastlines, allowing tidal areas to expand, is another example of a soft engineering approach to coastal flood defense. The choice between hard and soft engineering, or a combination of both, depends on various factors including the specific flood risk, environmental considerations, cost, and available space.