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under the Wetland Conservation Act) applies the 5 percent hydrological definition but if that is too short to allow the development of hydrophytic vegetation under normal conditions than the absence of hydrophitic vegetation would make those Type 1 wetlands non-jurisdictional. Type 1L—bottomland hardwoods—poses an equally difficult regulatory question. Tools for the evaluation of hydrology for non-cropped areas are much more data intensive and are also subject to precipitation event variability. Measurement tools for the determination of precipitation normalcy are a combination of evaluating annual precipitation and comparison to a 30-year rolling average along with extensive near ground surface early season hydrological monitoring. If the water levels are within 12" of the surface for less than 8.5 days in the general latitude of the Twin Cities (5 percent of the growing season), than the area is not wetland. If water levels are within 12" of the surface between 5 percent and 12.5 percent of the growing season (21 days in the general latitude of the Twin Cities) according to the 1987 Manual (Table 5 pg. 36), the area may be wetland but usually is not. However, the standard practice of the St. Paul COE is to declare any areas that exceed the 5 percent criteria to be judged jurisdictional wetlands. Areas with water levels within 12" of the surface in excess of 12.5 percent of the growing season are wetlands. No one has ever undertaken a scientific study to evaluate the relationship between the hydrological requirements and the presence of various wetland or non-wetland plant species. This is a critical, yet unanswered question. Some studies have been completed examining soil types and hydrological responsiveness but the link between plants and hydrology has yet to be made. Given the annual cost of jurisdictional decisions in terms of"lost land" opportunities, perhaps such a study would be prudent. The implications of regulatory misinterpretation are enormous in that it is likely that hundreds of acres of Type 1 wetlands are avoided or mitigated for each year when legitimately these areas are non-jurisdictional and could be developed. Avoidance or impact and mitigation can cost developers and ultimately, homebuyers, millions of dollars annually just in the developing seven-county Metropolitan Area. Mitigating a non jurisdictional Type 1 wetland impact at a 2:1 ratio reduces the usable land base unnecessarily. For every 50 acres of non-jurisdictional impact, 100 acres are removed from the land supply. At an average cost of$100,000 per acre, the cost to developers and ultimately to homeowners is $10,000,000 in just one year for just 50 acres. Type 2/3 Type 3 wetlands create the greatest classification difficulty from the perspective of de minimus qualification. A Type 3 wetland that is seasonally flooded (C) is typically characterized by reed canary grass whereas a Type 3 semi-permanently flooded wetland is more likely characterized by a growth of cattails. The reed canary wetlands are generally dry by late spring to early summer. By late summer, the water tables have