Yunnan Province in southwestern China, a formerly poor and clandestine region, is now experiencing rapid growth due to tourism and rural development. Mountainous northwestern Yunnan is home to the headwaters of three great river systems that run in parallel within about 30 km -- the Salween, Mekong and Yangtze Rivers, the former two flow through other Southeast Asian nations.

During a recent excursion to this area, I was shocked to see the extent of new mountain roads contributing heavy loads of sediment to these rivers. Major roads serving this region as well as smaller roads designed to link remote villages, hydropower plants and mining with cities are being built at a rapid pace.

While environmental groups tout the damage caused by deforestation, dams and unsustainable agriculture in the region, there was little evidence that these practices are widespread and polluting the headwaters of these river systems. Most of the current agriculture in the region appears to be rather sustainable and widespread forest clearing is not currently practiced. Few groups, including environmentalists, nongovernmental organizations, international donors and government agencies, clearly see the magnitude of the problems associated with sediment pollution from mountain roads.