Planning approaches to mitigate adverse human impacts on land-water ecotones

Land-inland water ecotones are environments of exceptional diversity, but are also highly vulnerable to impacts from human settlement. Settlement on floodplains and exacerbation of peak runoff from land-use changes have resulted in flood damage to human structures, leading in reaction to widespread efforts to control flooding through such measures as land drainage and construction of levees and artificial flood control channels. These measures increase flood hazard downstream and result in loss of valuable riparian and aquatic habitats. Similarly, human settlements along river banks may be threatened by natural channel migration, leading to ill-conceived bank stabilization projects, which eliminate riparian habitat. Environmental planning strategies to minimize these impacts include reducing stormwater runoff through use of permeable pavement, infiltration galleries, and detention basins; ordinances protecting urban streams and riparian corridors (from development, filling, etc.); prohibitions or restrictions on development on floodplains; retention of vegetative buffer strips along stream channels; maintenance of continuity of riparian corridors for wildlife and human use; use of alternatives to traditional flood control strategies; and release of flushing flows to mimic effects of natural floods below reservoirs.