Document Type

Thesis - Open Access

Award Date


Degree Name

Master of Science (MS)

Department / School

Civil Engineering


The first phase of the study sought to determine if the past quality of the Big Sioux River in that reach would have been sufficient to meet the adopted standards. The resulting paper (2) by John M. Herreid compared data for the quality parameters available at the Brandon, South Dakota sampling station with the recommended limits for various stream beneficial uses as set forth in the South Dakota Water Quality Standards. The appraisal by Herreid was completed before the addendum was attached to the standards. The major change of consequence in the addendum was essentially that of raising the minim m dissolved oxygen requirement for the river from 2.0 to 4.0 milligrams per liter (mg/1). Consequently the conclusions, as reached by Herreid regarding this parameter, may have been premature. Herreid, however, discussed the past river quality at Brandon in regard to both of these oxygen limits (2-34). This first phase of the study showed that the quality of river water, except for total coliform count, at the Brandon sampling station would have been within the limits established in the standards nearly all of the time. It also demonstrated that the river would have been classified in the intermittent stream category for significant portion of the time in past years and that the frequency of this classification will probably increase in the future. The river is in this category when the wastewater flow compromises 50 percent or more of the total flow of the river. While in this category, the dissolved oxygen requirements for the river water are substantially less stringent than for other categories. A relationship between low flows and poor water quality in the Big Sioux River was also established in Herreid's paper. For this reason it appeared that the quality standards would be most seriously threatened when the flow was just large enough so that the intermittent stream category was not in effect. Recognizing this potential problem, Herreid suggested that sufficient high quality dilution water, from proposed reservoirs upstream of the Big Sioux River and on Skunk Creek, be provided to avoid this problem. This paper reports on a second phase of the study initiated by Herreid. The prime objective of this phase of the study was to determine the relationship between dissolved oxygen, perhaps the most important single parameter, and various river conditions. Data from nine river sampling stations, covering the entire reach of the Big Sioux River affected by wastes discharged in the vicinity of Sioux Falls were utilized to define oxygen concentrations in the river. Thus an analysis of the variation of dissolved oxygen with various river conditions could be ascertained for this river reach.

Library of Congress Subject Headings

Water -- Analysis
Big Sioux River (S.D.)




South Dakota State University