Water Quality

Abstract

This monograph describes the water quality of New York Bight as measured by temperature, light, salinity, dissolved oxygen, various nitrogen and phosphorus forms, pH, heavy metals, coliform bacteria, and phytoplankton chlorophyll. Major water quality monitoring in the Bight, initiated in 1948, has been sporadic in the past with gaps from 3 to 10 years when no major sampling was conducted. These data indicate that bottom dissolved oxygen percent saturation levels in the disposal areas of the apex have decreased from 67% in 1949 to 30% in 1974. Surface total iron concentrations in the apex have increased from 20 u/l in 1949 to about 90 u/l in 1969, and are higher than background open ocean levels. Coliform bacterial influence appears to be confined to an area of 3.2 to 4.8 km (2 to 3 mi) radius from the discharge point of a sewage sludge barge dump. Nitrogen is generally the more important nutrient relative to phosphorus with respect to limiting phytoplankton growth in the Bight. Man’s impact on the water quality of the region appears to be significant with more than 50% of the total input of iron, copper, cadmium, chromium, suspended solids, and total phosphorus attributed to barge discharges alone. An overall analysis of New York Bight to quantitatively assess the relative impact of the major discharges is recommended.