Date of Award:


Document Type:


Degree Name:

Master of Science (MS)


Civil and Environmental Engineering

Committee Chair(s)

Bethany T. Neilson


Bethany T. Neilson


William J. Doucette


Michelle A. Baker


Surface water quality in the United States is managed by the U.S. Environmental Protection Agency (EPA) under direction of the Clean Water Act. Designated uses are required for all state waters. Numeric or narrative water quality standards provide measures to determine if each waterbody meets the intended use. Narrative standards typically include vague terminology that is difficult to interpret and this has led EPA to encourage states to develop numeric criteria for nutrients in all its streams, rivers, and lakes. These numeric nutrient criteria are intended to stave off the harmful effects of over-growth of aquatic plants which can result in poor water quality and even fish kills.

The purpose of this research is to aid the State of Utah in determining appropriate numeric criteria. These values can be determined using in-stream water quality models (in this case, QUAL2Kw), which accounts for the cause and effect relationships between nutrient addition and aquatic plant growth. One of the main tasks of this study is to identify how much data is needed to support this type of modeling and when and where it needs to be collected. Finally, a management tool was developed to automatically run model scenarios to help identify the nutrient loads that cause water quality problems.