In 1985 in US v. Riverside Bayview Homes Inc., the Supreme Court upheld the new Corps argument. Since 1989 jurisdictional wetlands describe those areas that meet the definition. The wetland definition only requires that under normal circumstances vegetation is typically adapted for survival in a saturated area. This is needed for practical limitations of rapid evaluations and reasonable amounts of effort. It is not possible to wait several years to test soil saturation levels, looking at plant life is a good enough evaluation.
Federal regulations regarding wetlands are an overlapping patchwork.
There is no specific wetland law. The US should create and restore to replace wetlands lost to further development. No net loss was adopted as policy by Bush and Clinton and agencies have been told this as executive direction. Takings issue - Issue is whether regulations which deny an owner from making economically viable use of land require compensation to the landowner. Remember that the constitution protects from unreasonable seizure and requires just compensation for property which is taken.