The Herring River estuary (Wellfleet, Cape Cod, Massachusetts) has been tidally restricted for over a century by a dike constructed near the mouth of the river. Behind the dike, the tidal restriction has caused the conversion of salt marsh wetlands to various other ecosystems including impounded freshwater marshes, flooded shrub land, drained forested upland, and wetlands dominated by Phragmites australis. This estuary is now managed by the National Park Service, which has plans to replace the dike and restore tidal flow to the estuary. To assist National Park Service land managers with restoration planning, study collaborators have been investigating differences in soil properties, carbon accumulation, and greenhouse gas fluxes across differing ecosystems within the Herring River Estuary. The U.S. Geological Survey collected continuous monitoring data (including water level, soil temperature, air temperature, and meteorological parameters). These datasets can help evaluate key ecosystem drivers to make predictions about potential changes as restoration commences.