Missing compensation: A study of compensatory mitigation and fish passage in georgia

Abstract

Thousands of permit applications are filed annually with the U.S. Army Corp of Engineers, requiring significant review efforts to ensure that applications conform to regulations, and that proposed activities avoid, minimize, and compensate for stream and wetland impacts. However, the effectiveness of this approach remains uncertain. We evaluated the effectiveness of those regulatory efforts using newly installed stream–road crossings as a case study because crossings are pervasive on the landscape and many U.S. Army Corp of Engineers jurisdictions have requirements that are aimed at minimizing crossing-induced impacts to fish passage. Specifically, we assessed whether requirements intended to facilitate fish passage were implemented, whether requirements resulted in fish-passable stream–road crossings, and whether the amount of construction-related stream impact that was authorized by permits corresponded to the amount of compensation that was required. Our analysis is devoted solely to stream–road crossings in Georgia that are permitted under nationwide permits, the permit type commonly used to authorize activities in streams throughout the United States. We found that no new crossings conformed entirely to the requirements intended to avoid and minimize impacts to fish passage. The measured total stream impact length in this study was 46.0% higher than the amount of impact proposed in permit applications for perennial streams, and 23.7% higher for intermittent and ephemeral streams. Only 30.6% of the perennial stream length affected in this study received compensation for impacts even though 90.9% of impacts qualified. Collectively, these results indicate that regulations and mitigation policies are not having their intended effects of providing fish passage or preventing net loss of streams in Georgia as required under the Clean Water Act. We recommend that decision makers undertake a more geographically comprehensive evaluation of stream impacts that are authorized by permits to thoroughly evaluate regulatory effectiveness and impacts to fish passage.