Salinity variations in the Connecticut River

Salinity distributions in the lower Connecticut River, measured during the years 1934 through 1939, show the influence of at least three factors: river discharge, tide, and wind. Salinity near the mouth is rather sensitive to changes in upland discharge; discharge events recorded at a gage 101 km upstream are followed a day or two later by markedly equivalent changes in salinity at the mouth. During average or greater‐than‐average discharge conditions the lower river has the characteristics of a ‘salt‐wedge’ estuary: the water on the bottom of the river may contain 15 parts of chloride per thousand at high tide, whereas the water in the same section of the river at low tide may be almost completely fresh. The effects of winds on salinity are uncertain, but such effects can be either local or related to regional effects of winds on the tides at the river mouth. (Key words: Estuaries; sea water; Connecticut; tides)