‘Traditional’ Flood Risk Management has mostly involved building things (‘Hard Engineering’) to deal with and control the flow of water. Be they flood walls, culverts, storm drains, etc., this style of engineering is based on strong engineering principles.
However, we are realising more and more – not that hard engineering is ineffective – but rather than it has shortcomings. There is more that we can do to manage the flow of water through a catchment, and manage the threat of flooding, than we can achieve through hard engineering alone.
‘Natural Flood Risk Management’ involves looking further throughout a catchment, holding water at the source wherever possible, and generally ‘Slowing The Flow’ of water through the entire catchment – all the way from the source to the sea.
The principle relies heavily on working with natural processes – such as enhancing the infiltration of water into the soil, or storing water in wetlands – or in mimicking natural processes – such as adding extra meanders into upstream rivers to slow the passage of water, or felling trees across small streams to create ‘leaky dams’ in the same way that trees would naturally fall and block waterways.
Overall, NFM applies a very holistic approach to environmental management, as healthier soils, greater numbers of trees and wetter wetlands all do store flood water, but they also provide other benefits to society and the environment, such as providing more sustainable agriculture, enhancing biodiversity and storing carbon.
Below are a few examples of NFM as covered in High Water Films, but this is an evolving field, and this list is by no means exhaustive. Find these ideas discussed and more in the High Water Film Library.