Wetlands Status and Trends
As mandated by the Emergency Wetlands Resources Act (Public Law 99-645), the NWI Program produces decadal Wetlands Status and Trends reports to Congress. These reports provide robust scientific estimates of the extent of seventeen wetland and deepwater habitats, as well as change in their area over time.
Five national and seven regional Status and Trends reports have been published to date, covering the years 1954 through 2009. Each report builds on the last, providing an invaluable historical perspective and increasing our understanding of landscape patterns and processes. The next report will cover the years 2009 through 2019.
National Status and Trends data are collected using a survey-based approach carried out within 5,048 four square mile plots randomly distributed across the conterminous U.S. Very fine spatial resolution imagery is used to determine area of wetlands, deepwater, and uplands within each plot, as well as change during the study period. Data quality is ensured through a multi-step process involving expert quality control, field verification, automated logic checks, and strategic technological improvements.
Accurate, up-to-date information on wetland area and change is an invaluable conservation asset, supporting the adaptive management of wetlands and their benefits, including those related to public health, safety, and recreation. Wetlands Status and Trends reports have catalyzed policy and management actions that substantially slowed net wetland loss. They continue to influence wetland conservation today by driving collaboration between federal, state, and local partners. Within the federal government, Status and Trends reports are used to guide the funding, planning, and implementation of wetland restoration and enhancement, species assessments in support of policy implementation (e.g., Endangered Species Act), strategic habitat conservation, ecosystem management, and more.