This course covers the basic hydrology, water quality, and water-related hazards that are associated with watersheds and are relevant to their management.  Watersheds are a fundamental natural division of the environment that determine the pathways of water, sediment, and biochemical materials on the surface of the Earth.  Historically, studies of aquatic systems have focused on local areas such as a hill slope, a stream reach, or an individual lake or pond. Over the past decade, however, there has been a concerted move by engineers, ecologists, planners, and policy makers to study aquatic systems at a broader "watershed scale" in order to appreciate the nature of inputs and the interactions between variables.  Although watersheds are defined independently of scale, by definition they include the entire upstream contributing area above a point on a stream and therefore involve a large number of physical and human processes that contribute water and materials.  This course elucidates the integrative perspective of environmental processes at the watershed scale with an emphasis on hydrological processes in the broad sense of the term.

Hydrology is a diverse field encompassing both the quantity and quality (volumetric and biochemical characteristics) of water, both on the surface and underground. Hydrology can be approached in many ways and involves many perspectives including engineering, agricultural, geological, geographic, environmental, public health, hazards, and planning viewpoints. Hydrologic studies can focus on any of several aspects of the water cycle including floods, droughts, water yields, drinking-water quality, point and non-point source pollution, geomorphic work by water, human impacts on hydrologic systems, aquatic ecology and restoration, and so forth. Obviously, no single course or textbook can cover all these hydrologic topics in depth, so prioritization and focus are required.

This course emphasizes a geographic perspective of watersheds by dividing topics into three components: physical hydrology, water and environmental quality, and water-related hazards. The physical hydrology component of the course covers the mechanical or volumetric aspects of surface, soil, and ground water that drive surface-water systems.  This emphasizes the generation of runoff and the quantity and timing of stream flow.  Evaluation of water and environmental quality includes the biological and physical constituents occurring in water, how they are generated and transported, their effects on the environment and society, and relationships between environmental quality and water quality.  The relevance, measurement, and interpretation of common constituents in water will be briefly covered, including dissolved and suspended solids, nutrients, dissolved oxygen, heavy metals, pathogens, etc. This water-quality section of the course is focused on two areas:  the role of natural treatment of water and the volumetrically important aspects of non-point source pollution; that is, soil erosion and sediment behavior in watersheds.  Natural treatment is a growing area of integrated water-resources management that holds the potential to reduce costs of water and sewage treatment and channel maintenance by restoring and protecting natural aquatic systems to enhance water quality and reduce sedimentation.  Water-related hazards include floods, droughts, pathogen outbreaks, and releases of chemical substances.  The course will emphasize flood hazards, basic concepts of risk assessment, strategies for mitigating flood risk, social vulnerability to flooding, and the structure of the National Flood Insurance Program.

In addition to the tripartite focus on hydrology, water quality, and flood hazards, the course will occasionally return to a theme of developing a global hydrologic and water resources perspective.  Modern global change studies are growing increasingly concerned with incorporating a better understanding of the hydrologic cycle.  For example, general circulation models have improved greatly over the past twenty years, but further improvements are reliant on better information about energy fluxes to the atmosphere driven by evapotranspiration.  These improvements are presently limited by insufficient information about global distributions of water.  To complement the watershed-scale focus of the course, therefore, a global perspective will be visited in each of the three topics of hydrology, water quality, and hazards.

A more detailed description of the topics to be covered is given in the lecture schedule.