Red List habitat classification > RLC - Freshwater habitats > RLC2.3 Permanent non-tidal, smooth-flowing watercourse

Permanent non-tidal, smooth-flowing watercourse

Quick facts

Red List habitat type code RLC2.3
Threat status
Europe Least Concern
EU Near Threatened
Relation to
Source European Red List habitat factsheet
European Red List of habitats reports
European Red List of habitats (Excel table)


This habitat includes permanent watercourses with non-turbulent water and their associated pelagic and benthic animal, algal and plant communities. The habitat includes slow-flowing rivers, streams, brooks, rivulets, rills and also relatively fast-flowing rivers with laminar flow. The bed is typically composed of sand or mud. Features of the river bed, uncovered by low water or permanently emerging, such as sand or mud islands and bars are treated as littoral zone (C3) and are not included in this habitat. This habitat includes stretches of streams and river at mid and low-altitude with an average flow velocity below 0.2 m/sec. Main physical differences between this habitat type and C.2.2b (Permanent non-tidal, fast, turbulent watercourses of plains and mountain regions with Ranunculus ssp.) are the lower flow velocity and the smaller grain size of the sediments. These two habitats may be related as segments of the same stream or river. The water is mesotrophic and buffered.

The vegetation is mainly constituted by rooted and floating Euro-Asiatic macrophytes, mainly with potamid, batrachid and utricularid growth forms, which belong to the Potamogetonion and Batrachion fluitantis communities. Potamid vegetation can be accompanied in slowly flowing parts of the river bed by nymphaeid species such as Nymphaea alba and Nuphar lutea. Also amphibian macrophytes may occur in this habitat with their aquatic form. Vegetation cover of the habitat, usually, does not exceed 30% of the total area of a river stretch.

Indicators of good quality:

  • Morphologically unaltered river bed and banks
  • Natural hydrological regime
  • Avoid of dominance of algae and floating algae beds (FLAB)
  • No or limited formation of floating mats of organic residuals
  • No or limited occurrence of exotic species
  • Limited extension of nymphaeid vegetation or species indicating high eutrophication

Characteristic species
For full habitat description, please download the habitat factsheet.

Threat status

Synthesis of Red List assessment

The habitat reaches the qualification of Near Threatened (NT) for the EU28, because of a large reduction in quality (criterion C/D1) and quantity (criterion A1) over the last 50 years. For the EU28+ the conclusion is Least Concern (LC). The assessment was carried out using data from about 46% of the EU28 countries and 31% of the additional EU28+ countries.
Red List Category Red List Criteria
Near Threatened C/D1
Red List Category Red List Criteria
Least Concern -

Confidence in the assessment

Red List of habitat categories and criteria descriptions

Pressures and threats

  • Mining, extraction of materials and energy production
    • Sand and gravel extraction
  • Biological resource use other than agriculture & forestry
    • Fishing and harvesting aquatic resources
  • Pollution
    • Pollution to surface waters (limnic, terrestrial, marine & brackish)
  • Invasive, other problematic species and genes
    • Invasive non-native species
  • Natural System modifications
    • Human induced changes in hydraulic conditions

Habitat restoration potential

The capacity of this habitat to recover naturally differs according to the type of damage that the habitat has undergone. If the damage had an impact on the hydrology and geomorphology the recovery time can be quite long and it is not always possible to restore the habitat. If the damage is represented by pollution of water bodies, the habitat can be restored in a relatively short time (10 years, or even less) through intervention and removal of the causes of pollution.

Trends in extent

Average current trend in quantity

Decreasing Decreasing
EU28 EU28+

Trends in quality

Average current trend in quality

Decreasing Decreasing
EU28 EU28+

Conservation and management needs

This habitat is threatened mainly by human activities. The conservation and management actions should involve in all countries the regulation of water abstraction, agricultural and industrial activities in the river basin (that are usually the main source of water pollution), fishing and extraction of sand and gravel from the river bed. Regulations and management actions have been already applied in some countries, favouring in this way the stabilization of the current habitat conditions. Management actions still not adopted by all countries are the maintenance of the environmental flow and the maintenance of natural buffer zones between the river beds and the fields. These zones are very important environmental filters for organic and inorganic pollutants and should be recreated for restoring and managing the habitat quality.

List of conservation and management needs

  • Measures related to agriculture and open habitats
    • Other agriculture-related measures
  • Measures related to wetland, freshwater and coastal habitats
    • Restoring/Improving water quality
    • Restoring/Improving the hydrological regime
    • Managing water abstraction
  • Measures related to hunting, taking and fishing and species management
    • Regulation/Management of fishery in limnic systems
    • Specific single species or species group management measures
  • Measures related to urban areas, industry, energy and transport
    • Urban and industrial waste management


For each habitat a distribution map was produced from a wide variety of sources indicating known and potential occurrences of the habitat in 10x10 km grids within Europe. Occurrences in grid cells were given in two classes: actual distribution from relatively reliable sources (surveys, expert knowledge), and potential distribution based on models or less reliable indicators. Please download the fact sheet to see the map.

Geographic occurrence and trends

EU28 Present or presence uncertain Current area of habitat (Km2) Recent trend in quantity (last 50 years) Recent trend in quality (last 50 years)
Austria Present unknown Decreasing Decreasing
Belgium Present 40 Decreasing Stable
Bulgaria Present 102 Decreasing Decreasing
Croatia Present 30 Decreasing Decreasing
Czech Republic Present 80 Decreasing Decreasing
Finland mainland Present 70 Decreasing Unknown
Aland Islands Present 70 Decreasing Unknown
France mainland Present unknown Decreasing Stable
Corsica Present unknown Decreasing Stable
Germany Present unknown Decreasing Decreasing
Greece (mainland and other islands) Present 0.23 Unknown Unknown
Crete Present 0.23 Unknown Unknown
East Aegean Present 0.23 Unknown Unknown
Hungary Present May-50 Decreasing Decreasing
Ireland Present unknown Decreasing Unknown
Italy mainland Present 9 Decreasing Decreasing
Sardinia Present 9 Decreasing Decreasing
Sicily Present 9 Decreasing Decreasing
Lithuania Present 150-160 Decreasing Decreasing
Netherlands Present 24-60 Decreasing Decreasing
Portugal mainland Present 3.42 Unknown Increasing
Portugal Azores Present 3.42 Unknown Increasing
Madeira Present 3.42 Unknown Increasing
Savage Islands Present 3.42 Unknown Increasing
Romania Present 0.3 Decreasing Decreasing
Slovenia Present 15 Decreasing Decreasing
Spain mainland Present 15 Decreasing Decreasing
Balearic Islands Present 15 Decreasing Decreasing
Canary Islands Present 15 Decreasing Decreasing
United Kingdom Present unknown Decreasing Decreasing
Northern Island Present unknown Decreasing Decreasing
Gibraltar Present unknown Decreasing Decreasing
Cyprus Uncertain unknown Unknown Unknown
Denmark Present unknown Unknown Unknown
Estonia Present unknown Unknown Unknown
Latvia Present unknown Unknown Unknown
Luxembourg Present unknown Unknown Unknown
Malta Uncertain unknown Unknown Unknown
Poland Present unknown Unknown Unknown
Slovakia Present unknown Unknown Unknown
Sweden Present unknown Unknown Unknown
EU28 + Present or presence uncertain Current area of habitat (Km2) Recent trend in quantity (last 50 years) Recent trend in quality (last 50 years)
Bosnia and Herzegovina Present 400 Decreasing Decreasing
Switzerland Present unknown Decreasing Decreasing
Albania Present unknown Unknown Unknown
Andorra Uncertain unknown Unknown Unknown
Faroe Islands Uncertain unknown Unknown Unknown
Guernsey Uncertain unknown Unknown Unknown
Iceland Uncertain unknown Unknown Unknown
Isle of Man Uncertain unknown Unknown Unknown
Jersey Uncertain unknown Unknown Unknown
Kaliningrad Uncertain unknown Unknown Unknown
Kosovo Present unknown Unknown Unknown
Liechtestein Uncertain unknown Unknown Unknown
Former Yugoslavian Republic of Macedonia (FYROM) Present unknown Unknown Unknown
Montenegro Present unknown Unknown Unknown
Norway Mainland Uncertain unknown Unknown Unknown
Svalbard Uncertain unknown Unknown Unknown
Jan Mayen Uncertain unknown Unknown Unknown
San Marino Present unknown Unknown Unknown
Serbia Present unknown Unknown Unknown

Extent of Occurrence, Area of Occupancy and habitat area

Extent of Occurrence (EOO) (Km2) Area of Occupancy (AOO) Current estimated Total Area Comment
EU28 8070300 7998 812-903 Only 50% of the countries provided the total area.
EU28+ 7998 1282-1373 Only 33% of the countries provided the total area.
AOO = the area occupied by a habitat measured in number of 10x10 km grid cells.
EOO = the area (km2) of the envelope around all occurrences of a habitat (calculated by a minimum convex polygon).

Characteristic species

Not available

Vegetation types

Relation to vegetation types (syntaxa)

Not available

Other classifications

Not available
European Environment Agency (EEA)
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1050 Copenhagen K
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