Sustainable Urban Drainage Systems (or SUDS) are a sequence of water management practices, green infrastructures and measures designed to drain surface water in a manner that mimics the natural hydrologic cycle and will provide a more sustainable approach to rainwater management than what has been the conventional grey infrastructure practice of routing run-off through a pipe to a receiving watercourse.

Efforts (either monetary outlays or consumption of any other resources, such as time) of administering, monitoring, and enforcing a NWRM. Policy-making involves political costs that are absent in private exchanges.

The reconstitution of the alluvial mattress consists in leveling-up the river bed and/or reactivating the bank erosion in order to stop the incision of the river bed. It can allow better connection with side arms, level-up the water level at low flow periods, diversifying flows (depth, substrate, speed), diversify habitats and increase retention times.
- Based on Stella definitions, adapted by NWRM project experts and validated by the European Commission