Publication Date


Document Type


First Advisor

Bowden, Kenneth Lester

Degree Name

M.S. (Master of Science)

Legacy Department

Department of Geography


Water--Pollution--Illinois--Measurement; Drainage--Illinois; Water quality--Illinois--Measurement; Ammonia


Two major water quality problems are associated with the presence of ammonia in a water body: 1) depression of dissolved oxygen by exertion of chemical oxygen demand and 2) direct toxicity to in-stream organisms, literature on ammonia toxicity indicates the un-ionized (NH₃) form of ammonia to be the problem pollutant. This investigation examines two issues concerning un-ionized ammonia. The first concerns the relationships of un-ionized ammonia in Illinois streams with respect to total ammonia-nitrogen, pH, temperature, and field dissolved oxygen. The second investigates sources of un-ionized ammonia from urban and rural watersheds. Nine Illinois stream drainage basins were selected for this study. These basins are categorized into three groups — 1 ) mean NH₃ values less than .02 mg/l (the USEPA Water Quality Criteria for un-ionized ammonia), 2) greater than .02 mg/l and less than .20 mg/l, and 3) greater than .20 mg/l. The nine study basins were analyzed for general basin data trends as well as seasonal trends. This was done to determine the general behavior of un-ionized ammonia in relation to total ammonia-nitrogen, temperature, pH, and field dissolved oxygen. In addition, factor analyses were performed on the data including chloride, fecal coliform bacteria, nitrates/nitrites, phosphorous, and sulfate as surrogate variables for on-land sources. Results indicated that elevated concentrations of total ammonia-nitrogen along with high temperatures are the major contributors to high un-ionized ammonia concentrations in the basins studied. However, the numerous factors contributing to total ammonia-nitrogen concentrations must be taken into consideration when determining the characteristics of un-ionized ammonia. The factor analysis results indicate that non-point sources of un-ionized ammonia in urban areas are urban runoff and atmospheric fallout, the latter of which deserves further study. Major non-point sources of un-ionized ammonia in rural areas are runoff from fertilized fields, runoff from feedlots, water softener discharges, and road salts.


Includes bibliographical references.


v, 60 pages




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