L' etude d' impact pour les cours d' eau: ses possibilites et ses limites.
1992
Samson P.
Impact studies on watercourses have, over the last years, turned out to be vital tools for better management of a drainage basin's natural resources. However, experience has helped us to observe that major shortcomings exist in the present implementation process. The main objective of these studies is to provide insight into potential impacts of planned river improvements and to moderate them as far as possible. However, it would appear that two major elements are not taken into consideration in these forecasts: the weather and the contractors'quality of workmanship. Watercourses are dynamic environments which are closely linked to meteorological conditions. A recently improved water course generally shows greater fragility due to the re-designing which has been carried out. A combination of this fragility factor with flash-floods can have catastrophic results. For impact studies to reflect the true picture with regard to river improvements already carried out, a post-project report must be drawn up a full year after completion in order to validate the impact study's initial assumptions. All who have had the opportunity of closely monitoring a building site involving river improvement work know that the greatest negative impact is generally caused by the contractor who has been awarded the commission on the basis of the best (i.e. lowest) offer of services. To remedy this situation, technical sessions are required to improve the 'environmental performances' of the contractor and his personnel regarding the handling of heavy machinery. Several governmental and semi-governmental agencies in Quebec have joined forces in order to develop the environmental work ethics of those dealing with heavy machinery.
显示更多 [+] 显示较少 [-]