Date of Award:


Document Type:


Degree Name:

Master of Science (MS)


Watershed Sciences


Richard H. Hawkins


The purpose of this study was to quantify the chemical nature of the Chicken Creek waters, and to investigate the variability and causes of that observed chemistry. The three objectives of the study were: 1) inventory the chemistry of the water produced by the subject watersheds, 2) determine chemical budgets for the watersheds, and 3) identify the sources of the primary chemical components.

Chemical surveys were made: 1) on the stream exiting from each gaged watershed, 2) at various points within the West Branch drainage network, 3) of the atmospheric inputs (rain, snow, and dust), 4) of the soil solution, and 5) of the soil itself. Data were also collected on the volume and distribution of rain and snow entering the watersheds, and the volume and timing of the streamflow leaving.

Streams were found to be dilute solutions with nearly neutral pH, containing Ca, Mg, Na, K, HCO3, SO4, and Cl; with NO3 and PO4 present in lesser quantities. The observed chemistry was quite dynamic with the CO2/CO3/HCO3 equilibrium system having a significant influence. In a more general sense, the water chemistry appeared to be a mixture of surface runoff, with chemistry approaching that of precipitation; and subsurface flow, with chemistry near that of soil solution.

The watersheds themselves are the source of most of the chemical constituents, with only NO3 and PO4 appearing to be consumed within the watersheds. On a per unit area basis, the West Branch watershed was shown to produce significantly more water, of higher chemical concentration than the East Branch. Possible explanations for such variability are discussed, e.g., non-uniform distribution of the snow pack and varying chemical activity of soils.