Difference between revisions of "Reduce anthropogenic flow peaks"
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==General description == | ==General description == | ||
| − | + | Water quantity and the flow regime can be altered by different factors such as changes in land cover, soil structure and compacting, loss of floodplains and wetlands, and stormwater runoff from urban areas. Loss of water retention combined with accelerated runoff typically increases the frequency and magnitude of flood peaks but also reduces the availability of water to streams during the prevailing low flow (base flow) periods. | |
| − | * | + | |
| − | * | + | Preferably, a more natural flow regime can be restored by increasing water infiltration and retention at the catchment scale by e.g. changes in land cover and floodplain restoration (see measure [http://wiki.reformrivers.eu/index.php/Improve_water_retention#General_Description/ Improve water retention]) since this addresses both, increased peak flows and reduced base flows. An alternative local end-of-pipe solution to reduce peak flows caused by stormwater runoff are retention and detention basins, which are of special importance for small rivers where single effluents may already cause massive erosion, affect water quality, and organisms are flushed away (catastrophic drift). |
| − | [ | + | |
| + | Please note: | ||
| + | * polders are not covered here but in the fact-sheet [http://wiki.reformrivers.eu/index.php/Link_flood_reduction_with_ecological_restoration#General_description/ Link flood reduction with ecological restoration] | ||
| + | * anthropogenic peak flows are also caused by hydropeaking; [http://wiki.reformrivers.eu/index.php/Modify_hydropeaking#General_Description/ read more about measures to modify hydropeaking here] | ||
| + | * this fact-sheet is equivalent with [http://wiki.reformrivers.eu/index.php/Reduce_anthropogenic_flow_peaks#General_Description/ Reduce anthropogenic flow peaks] | ||
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==Applicability == | ==Applicability == | ||
The construction of stormwater retention basins is recommended to prevent direct urban runoff into streams. These facilities store surface runoff in events of heavy rain and prevent flooding. Stormwater retention basins can be understood as artificial lakes or ponds (open and green or concrete). Another way to buffer runoff is an underground storage system (e.g. tanks). Constrains could rise due to the area needed to build retention basins. If possible, open and near-natural systems should be favored (MKULNV NRW). A less technical approach to mitigate surface runoff is the use of open, vegetated space within a city (has to be involved in urban planning). Open areas (e.g. parks, green areas) can be expected to prevent urban runoffs by retaining rainwater (storage and evapotranspiration). It further increases infiltration to groundwater. | The construction of stormwater retention basins is recommended to prevent direct urban runoff into streams. These facilities store surface runoff in events of heavy rain and prevent flooding. Stormwater retention basins can be understood as artificial lakes or ponds (open and green or concrete). Another way to buffer runoff is an underground storage system (e.g. tanks). Constrains could rise due to the area needed to build retention basins. If possible, open and near-natural systems should be favored (MKULNV NRW). A less technical approach to mitigate surface runoff is the use of open, vegetated space within a city (has to be involved in urban planning). Open areas (e.g. parks, green areas) can be expected to prevent urban runoffs by retaining rainwater (storage and evapotranspiration). It further increases infiltration to groundwater. | ||
Revision as of 12:01, 22 December 2015
Contents
- 1 General description
- 2 Applicability
- 3 Expected effect of measure on (including literature citations):
- 4 Temporal and spatial response
- 5 Pressures that can be addressed by this measure
- 6 Cost-efficiency
- 7 Case studies where this measure has been applied
- 8 Useful references
- 9 Other relevant information
General description
Water quantity and the flow regime can be altered by different factors such as changes in land cover, soil structure and compacting, loss of floodplains and wetlands, and stormwater runoff from urban areas. Loss of water retention combined with accelerated runoff typically increases the frequency and magnitude of flood peaks but also reduces the availability of water to streams during the prevailing low flow (base flow) periods.
Preferably, a more natural flow regime can be restored by increasing water infiltration and retention at the catchment scale by e.g. changes in land cover and floodplain restoration (see measure Improve water retention) since this addresses both, increased peak flows and reduced base flows. An alternative local end-of-pipe solution to reduce peak flows caused by stormwater runoff are retention and detention basins, which are of special importance for small rivers where single effluents may already cause massive erosion, affect water quality, and organisms are flushed away (catastrophic drift).
Please note:
- polders are not covered here but in the fact-sheet Link flood reduction with ecological restoration
- anthropogenic peak flows are also caused by hydropeaking; read more about measures to modify hydropeaking here
- this fact-sheet is equivalent with Reduce anthropogenic flow peaks
Applicability
The construction of stormwater retention basins is recommended to prevent direct urban runoff into streams. These facilities store surface runoff in events of heavy rain and prevent flooding. Stormwater retention basins can be understood as artificial lakes or ponds (open and green or concrete). Another way to buffer runoff is an underground storage system (e.g. tanks). Constrains could rise due to the area needed to build retention basins. If possible, open and near-natural systems should be favored (MKULNV NRW). A less technical approach to mitigate surface runoff is the use of open, vegetated space within a city (has to be involved in urban planning). Open areas (e.g. parks, green areas) can be expected to prevent urban runoffs by retaining rainwater (storage and evapotranspiration). It further increases infiltration to groundwater.
Expected effect of measure on (including literature citations):
- Decreased drift due to lower flow peaks,
- Increased chemical condition (less pollution) which has positive effects on stream biota.
Temporal and spatial response
Not available
Pressures that can be addressed by this measure
Cost-efficiency
Not available
Case studies where this measure has been applied
Useful references
- REFORM Wiki - Modify hydropeaking : http://wiki.reformrivers.eu/index.php/Modify_hydropeaking
- USGS - Runoff (surface water runoff) : http://water.usgs.gov/edu/runoff.html (accessed October 7th, 2015).
- MKULNV NRW (Ministerium für Klimaschutz, Umwelt, Landwirtschaft, Natur- und Verbraucherschutz des Landes Nordrhein-Westfalen): http://www.flussgebiete.nrw.de/index.php/Ma%C3%9Fnahmen/M1.0 (German)
