PPS 15 Planning and Flood Risk (Revised)·Page 44·6.49
Environmental impacts of culverting and canalisation
Culverting and canalisation are environmentally unsustainable, adversely affecting visual amenity, landscape quality, ecological integrity and biodiversity. They create barriers to fish passage, cause unnatural sediment movement, increased erosion, and hinder watercourse recovery.
Culverting and canalisation are generally considered to be environmentally unsustainable as such operations can adversely impact upon visual amenity in the built environment and can damage or impair the landscape quality, ecological integrity and biodiversity of watercourses. Culverting creates barriers to the passage of fish, while the higher flow velocities generated cause the unnatural movement of sediment, increased erosion downstream and hinder the future recovery of the watercourse.
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