Reaeration coefficients of six streams in New York; a comparison of results obtained by a hydrocarbon-gas tracer method with those obtained by radioactive tracers and predictive equations

Stream-reaeration measurements were made in selected reaches on six streams in New York State from 1978 to 1981 with hydrocarbon-gas and dye tracers. The sites were Canadaigua Outlet near Canadaigua, Oswego River at Fulton, Hudson River at Fort Miller, Cayadutta Creek near Johnstown, Chenango River near Morrisville, and Payne Brook near Hamilton. The reaches represent a wide range of discharge, water-surface slope, velocity, and streambed composition. Flows ranged from less than 2 cu ft/sq on the Chenango River to 4,100 cu ft/sq on the Hudson River, and water-surface slope within the reaches ranged from less than 1 foot/mile on the Hudson and Oswego Rivers to more than 50 ft/mi on Cayadutta Creek. The corresponding stream-reaeration coefficients ranged from 0.77 units/day for one reach on Canadaigua Outlet to 52 units/day on Cayadutta Creek. The reaeration coefficients for Canadaigua Outlet compared well with those obtained on the same reach 10 years earlier by radioactive tracers. Comparison of measured reaeration coefficients with those calculated from 10 predictive equations based on stream-channel characteristics yielded mean errors that range from 51% to 103%. No single equation gave reliable accuracy for all stream reaches. (USGS)