Fish life in relation to polluting influences in the Lake Champlain watershed

Carpenter, K. E.

Effluents from the soda-pulp process, while toxic at high concentrations, have little or no effect when diluted in the stream, but the pulp-fiber discharged in the "white-water" may in certain cases cause suffocation of the fishes, as well as ruining the sources of their food-supply and destroying spawning-beds. The effluent from sulphite mills is far more objectionable in character, from both standpoints. Adoption of the Robeson Process of recovery of sulphite liquor at one mill has led to a great improvement, but constant leakages, apparently to some extent unavoidable in view of the corrosive action of the fluid, render a considerable reach of the stream entirely unproductive and offensive to smell and sight. The state of affairs below soda-pulp mills can be greatly improved by careful use of save-alls and screening and burning of lime-sludge. The ideal treatment in all cases would involve dilution of effluents in an artificial or natural backwater before allowing them to enter the stream. In some of the situations examined, pollution from town-sewage was a serious complicating factor.