Natural Water Retention Measures (NWRM) are multi-functional measures that aim to protect water resources and address waterrelated challenges by restoring or maintaining ecosystems as well as natural features and characteristics of water bodies using natural means and processes.
Typical NWRM include riparian woodlands, agricultural and upland drainage modifications, non-floodplain wetlands, instream structures (e.g. large woody debris), and offline storage ponds.
It has been demonstrated that NWRM improve water quality and can be effective at reducing flooding in small catchments for frequent floods, that is, in catchments less than 10km2 and for floods with a one in ten chance of occurring in any given year. NWRM also achieve multiple benefits beyond water quality and flood risk reduction, including habitat creation, climate regulation, and the provision of amenity.
The benefits and appropriate application of NWRM are extensively documented in the Scottish Environment Protection Agency Natural Flood Management Handbook, the Environment Agency (UK) Working with Natural Processes Handbook, and the EU Commissions NWRM web-portal.