The purpose of the Clean Water Act (CWA) is to “restore and maintain the chemical, physical, and biological integrity of the Nation’s waters.” Section 404 of the CWA, which is one of the mechanisms used to achieve this goal, regulates the discharge of fill into “waters” of the United States. The CWA defined waters of the United States to include “tributaries to navigable waters, interstate wetlands, wetlands which could affect interstate or foreign commerce, and wetlands adjacent to other waters of the United States.” (Over the years, there has been much debate about this definition but that is a subject for a different post.) In the case of wetlands, when an unavoidable impact occurs mitigation is typically required. For example, if a 10 acre wetland is destroyed during the course of building one of those ‘Big Box’ stores, the owners of that Big Box store would be required to provide compensatory mitigation for that loss. In other words, they would be required to replace “that” which they destroyed.
Sounds straightforward and fair, right? The problem is that defining what “that” means is a complicated exercise. Is it acre-for-acre? Should the same type of wetland be replaced (marsh for marsh, and not marsh for fen)? What about the quality or integrity of the wetland? Should that be replaced? Or, maybe only certain values of the wetland need to be replaced (good duck habitat for good duck habitat). And, how do all these different replacement “currencies” relate to the “chemical, physical, and biological integrity” of our Nation’s waters? Originally, acreage was the currency of choice. In some cases, it remains such. However, wetland function soon arose as a refined currency by which to measure wetland loss or gain. The ecosystem characteristics related to a select set of ecosystem functions were identified. Because ecosystem functions can be very costly to measure, these ecosystem characteristics became surrogate measures for function. They have been used to measure wetland loss/gain under the assumption that they accounted for loss/gain of wetland function. However, very little research has been conducted to determine whether changes in these ecosystem characteristics reliably predict changes in the rate and delivery of ecosystem functions. Considering the wetland regulatory system relies heavily on this assumption, it was very disheartening to read the paper highlighted in this article Restored Wetlands Rarely Equal Condition of Original Wetlands.
As someone who has spent many years contemplating and studying the ecological integrity of wetland ecosystems, the results of this study were no surprise. My humble opinion has always been that we place too much faith in our ability to restore Nature. I don’t mean to imply we should abandon the practice of restoration rather that we use it under the appropriate circumstances. Pro-active restoration–the act of restoring ecosystem integrity for the sake of the ecosystem and its critters–is a much needed option in the conservationists’ toolbox. However, restoration in the context of compensatory mitigation–being required to restore something in order to get permission to destroy something else–is a questionable exercise, especially when the expectation is that there will be “No Net Loss” of the ecosystem. I don’t deny there are restoration successes but as this study has shown, more often than not we don’t get back what we lose.
John Weaver offers a quote that I think sums up the issue. Although he is talking about prairies, his analogy applies to any ecosystem:
“The prairie provides us with a background against which we may measure the success or failure of our own land use and management….[it] is the outcome of thousands of years of sorting of species and adaptations to soil and climate…prairie is much more than land covered with grass. It is a slowly evolved, highly complex organic entity, centuries old”
–John E. Weaver