natural area

In the past, various activities were undertaken to straighten rivers, such as the stabilisation of river banks with concrete or other types of retention walls.ﾠ Such actions limited riversﾒ natural movements, leading to degradation of the river, increased water flow, increased erosion and decreased biodiversity.ﾠ Natural bank stabilisation reverses such activities, allowing rivers to move more freely.ﾠ Where bank stabilisation is nevertheless necessary, such as in residential areas, natural materials such as roots or gravel can be used.ﾠ Natural materials are preferable as they allow water to infiltrate into the bank.ﾠ They also provide better living conditions for aquatic fauna.
- Based on Stella definitions, adapted by NWRM project experts and validated by the European Commission

In the past, rivers flows have been modified through channelisation, embankments or modification of river beds. Those modifications were aiming at flood prevention or supporting changes of agricultural practices for example. This has led to uniformed flows in the rivers and often having effect on the water time transfers. Current practices for revitalisation of flowing waters are trying to create the conditions for diversifying the water flows, inducing more diversity in habitats for fauna but also increasing the water time transfers in order to prevent flash floods in the downstream areas for example.
- Based on Stella definitions, adapted by NWRM project experts and validated by the European Commission

Planting and maintaining tree cover in near-stream areas can have multiple benefits including erosion and nutrient leaching control. They will also slow the stream velocity during high flow flood events and may have beneficial effects on stream temperature. Maintaining treed forest buffers during clearcutting can help minimizing the adverse effects of forestry on water quality and may have additional biodiversity benefits.
- Based on Stella definitions, adapted by NWRM project experts and validated by the European Commission

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

In the past, rivers have been straightened by cutting off meanders (historically, many rivers in northern and western Europe have been straightened and channelized to facilitate log floating and/or speed up the drainage of water and control/limit the river bed movements).ﾠ Re-meandering is bringing a river back closer to its naturally meandering state by creating a new meandering course and by reconnecting cut-off meanders.ﾠ Re-meandering slows down the flow of a river.ﾠ The new form of the river channel creates new flow conditions and very often also has an impact on sedimentation.ﾠ The newly created or reconnected meanders also provide habitats for a wide range of aquatic and land species of plants and animals.
- Based on Stella definitions, adapted by NWRM project experts and validated by the European Commission

The sloping side of any hollow in the ground, especially when bordering a river. 

Coarse woody debris is a key stream habitat feature used by fish and other organisms. Coarse woody debris can also help to lower flow velocity in streams.
- Based on Stella definitions, adapted by NWRM project experts and validated by the European Commission

A gabion (from Italian gabbione meaning "big cage"; from Italian gabbia and Latin cavea meaning "cage") is a cage, cylinder, or box filled with rocks, concrete, or sometimes sand and soil for use in civil engineering, road building, and military applications.

The suppression of lateral constraints consists in removing some bank protection in order to enhance lateral connection of the river, diversifying flows (depth, substrate, speed), diversify habitats but also capping floods in the mainstream.
- Based on Stella definitions, adapted by NWRM project experts and validated by the European Commission

Lakes are by definition water retention facilities; they store water (for flood control) and provide water for many purposes such as water supply, irrigation, fisheries, tourism, etc.ﾠ In addition, they serve as sinks for carbon storage and provide important habitats for numerous species of plants and animals, including waders.ﾠ In the past, lakes have sometimes been drained to free the land for agriculture purposes, or have simply not been maintained and have silted up.ﾠ Restoring lakes is re-introducing them where they have been in former times or revitalising them.
- Based on Stella definitions, adapted by NWRM project experts and validated by the European Commission