J.B. Ruhl, property law professor at the FSU College of Law, found that the banks redistribute wetlands from urban areas to rural ones, taking away crucial environmental benefits such as flood control from cities.
The benefits of wetlands to wildlife and people are well established. In addition to serving as nurseries for most fish and homes to wildlife and birds, they are essential to drinking-water supply, absorbing water during wet seasons and releasing it during dry times. They filter water to keep it clean. They prevent shore erosion and wildfires, and perhaps most important, they provide flood control. Hurricane scientists say that in coastal areas each square mile of wetlands absorbs enough water to knock a storm surge down by one foot.
The Clean Water Act of 1972 required developers to create new wetlands if they paved over others -- "mitigation." But regulators frequently didn't enforce the law. Meanwhile, three-fourths of the artificial wetlands failed. And many of the mitigation projects initially thought successful were later found to be ecologically worthless because they were so small and isolated.
Looking for better solutions, regulators, led by the state of Florida -- which has lost more wetlands than any other state, with 9.3 million acres filled in or paved over by the late 1980s -- opened the door to mitigation banks. Private companies preserve or restore a wetland off-site and sell credits to developers who need to destroy a wetland to build a subdivision or other project. Over the years, suspicion has grown that the banks aren't living up to their ecological promise ("Swamp Repair," May 2000, FloridaTrend.com). Ruhl and Duke law professor James Salzman did the first comprehensive, empirical study about the impact of the banks on people.
"We're moving wetlands very long distances from the urban populations."
Ruhl and Salzman collected information about all of Florida's active and sold-out banks and the development projects that bought the credits. They found a shift of wetlands from urban to rural areas, and significant differences between bank areas and project areas in terms of population density, median income and percentage of minorities. They also found considerable distance between the banks and their trade-off projects. "We're moving wetlands very long distances from the urban populations," says Ruhl.
Supporters of the banks argue that urban areas require developers to build critical functions such as stormwater control into their projects. Ruhl says a stormwater pond can't duplicate the functions of a wetland, and moreover, a completely different set of regulators oversees wetlands mitigation (the state and the U.S. Army Corps) and stormwater ponds (local government). The study concluded that regulators should more closely monitor the bank transactions and make corrections. For example, authorities could charge a fee for credits purchased from faraway banks and use that to fund public acquisition of urban wetlands.