To be considered a wetland, an area must have: hydrology that results in wet or flooded soils soils that are dominated by anaerobic processes, and biota, particularly rooted vascular plants ...

Research on wetlands hydrology led to a better understanding of the role of wetlands in the regional hydrology and to invitations to serve on Federal panels developing guidelines for wetlands ...

“This sickening gift to polluters will allow wetlands, streams and rivers across a vast stretch ... a major river — a myopic legal interpretation that ignores the complex hydrology of the arid western ...

and other changes to the land's floodplain and wetlands, "are likely to result in secondary impacts including diminished habitat quality, unanticipated changes in hydrology, increased pollution ...