HEADWATER CONTROL IN NORTH AMERICA

摘要

The effects of land use on water yield, water quality, flooding and aquatic biota are of increasing concern to government agencies and the public in North America. The government has responded to this challenge by downloading the responsibility to community groups and multi-stakeholder boards. For watershed management, the challenges come primarily from inappropriate forest harvesting methods, agricultural intensification, urban storm water discharge and recreational development in headwater areas. While there is a good understanding of the extent of the problem, solutions and rehabilitation projects are still too new to claim any widespread success. It is the cumulative effect of these impacts that are the most difficult to assess. A massive effort is underway to educate public interest groups and encourage them to take an active part in watershed rehabilitation. Source control, best management practices, the use of stream buffer zones and detention ponds (to filter and retain pollutants before they enter streams) and protecting vulnerable areas are some of the rehabilitation options that show most progress. The distribution of information and education programs via the Internet is proving effective in educating the public.