acidic (NAPAP, 1990). A systematic restoration of U.S. streams and rivers, along with continued pollution controls, is essential.

Conditions of Wetlands

Wetlands provide essential functions, including flood control, soil and nutrient retention, and wildlife habitat. In some agricultural areas such as the state of California, more than 90 percent of the natural wetlands have been drained or filled. Many riverine wetlands, so essential to water storage, aquifer recharge, and wildlife, have been converted to agricultural areas or destroyed by channelization and urban sprawl. The average rate of wetland loss in the conterminous United States from the mid-1950's to the mid-1970's was nearly 460,000 acres per year, leading to an aggregate loss over all time of about half the wetlands believed to have been here before settlement began — an area greater than Massachusetts, Connecticut, and Rhode Island combined (The Conservation Foundation, 1988; Council on Environmental Quality, 1989). The rate of wetland loss declined to approximately 290,000 acres per year from 1975 to 1984 (Dahl and Johnson, 1991).

Although a ''no-net-loss" policy for U.S. wetlands was advocated by President George Bush as a presidential candidate in 1988, the policy's implementation strategy is still being developed at this writing (fall, 1991). During his campaign, then-Vice President Bush declared that all existing wetland should be preserved. His stand was an endorsement of a no-net-loss policy recommendation made by the National Wetlands Policy Forum, a broadly based group including representatives of both industry and environmental groups. In 1989, the U.S. Environmental Protection Agency and three other federal agencies implementing wetlands protection provisions of the Clean Water Act of 1977 (P.L. 95-217), as amended in 1980, produced a wetland delineation manual to help decision makers identify wetlands. This federal manual confirmed a 1983 U.S. Fish and Wildlife Service estimate that 100 million acres of the nation are wetlands. Since the appearance of the manual, however, a number of interest groups, lawmakers, and several federal agencies urged the administration to make the definition of wetlands less encompassing, thereby reducing the amount of land designated as wetlands. These groups have contended that the federal definition of wetlands contained in the wetland delineation manual was so broad as to include areas that are not truly wetlands and that have long been regarded as dry. It is essential that this matter be resolved in order to develop a workable restoration policy.

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