Appropriate design of roads and stream crossings

Code: 
F08
Sector: 
Forest
The complete description of the NWRM: 
Summary: 

Forest access roads and other roads in rural areas often cross streams and other small watercourses. Design and material used in forest road building may have strong impact on erosion risk and water quality in streams. The bridges or culverts used to cross these watercourses must be designed appropriately if negative impacts on the aquatic environment are to be minimized. Poorly designed or poorly implemented stream crossings can have numerous negative effects on the aquatic environment including increased sediment mobilization and changes in flow patterns. For example, flooding upstream of the road crossing can occur when the bridge or culvert is unable to transport a sufficient volume of water.  Such floods can also wash out bridges or stream crossings, leading to increased costs for the road owner and downstream sediment pollution. Increased sediment mobilization results in loss of aquatic habitat and may extirpate threatened species including freshwater pearl mussel as well as destroying spawning habitat.

Illustration(s): 
River with inappropriate design

River after designing a proper crossing

Source: http://www.huronpines.org/projectinfo.asp?pjt=pv&pid=37

Possible benefits with level: 
Benefits Levelsort descending
BP10 - Reduce erosion and/or sediment delivery High
BP12 - Create aquatic habitat High
ES2 - Fish stocks and recruiting High
ES4 - Biodiversity preservation High
ES8 - Erosion/sediment control High
PO7 - Prevent surface water status deterioration High
ES1 - Water storage Low
ES7 - Flood risk reduction Low
ES12 - Navigation Low
PO2 - Improving status of physico-chemical quality elements Low
PO11 - Better protection for ecosystems and more use of Green Infrastructure Low
PO12 - More sustainable agriculture and forestry Low
ES9 - Filtration of pollutants Low
BP4 - Slow river water Medium
BP8 - Reduce pollutant sources Medium
PO1 - Improving status of biology quality elements Medium
PO3 - Improving status of hydromorphology quality elements Medium
PO9 - Take adequate and co-ordinated measures to reduce flood risks Medium
PO10 - Protection of important habitats Medium
PO13 - Better management of fish stocks Medium
PO14 - Prevention of biodiversity loss Medium
BP2 - Slow runoff Medium
BP1 - Store runoff Medium
BP3 - Store river water Medium
ES11 - Aesthetic/cultural value Medium
Case study(ies): 
Last updated: 10 Jun 2015 | Top