Hydrologic Science and Engineering

	Introduction Research Faculty Facilities and Resources Courses Qualifying Exam
Correlation between July-October (JASO) flows of the Blue Nile River and sea surface temperature (SST)

Program Coordinator:
Jorge A. Ramírez
ramirez@engr.colostate.edu
(970) 491-7621

Introduction

Hydrology is an Earth science focusing on the movement, storage, and properties of water in the environment as well as the interaction of water with environmental systems and human activities.  At the center of this field of study is a set of physical processes such as precipitation, evaporation, transpiration, infiltration, and streamflow that transfer water in the environment and affect water quality.  Hydrology involves the application of mathematical descriptions of these processes as well as statistical methods to account for the spatial variability and temporal dynamics in hydrologic systems.  Many tasks in civil and environmental engineering such as water supply planning, storm sewer design, irrigation system design, water rights administration, stream restoration, environmental protection, floodplain planning and management, and drought mitigation involve some type of hydrologic analysis, modeling, and decision making.  Hydrology is also closely related to numerous policy issues such as the potential effects of climate change, aridity, deforestation, and cloud seeding.

The Hydrologic Science and Engineering (HSE) program provides a balanced program of study in the science of hydrology and its application to both engineering and interdisciplinary problems.  The program helps students develop a thorough understanding of hydrologic processes as well as their variability and interrelationships.  Students gain an in-depth understanding of numerical modeling (both physically-based and stochastic), statistical methods, and geographical information systems (GIS).  The program also helps students gain a broad understanding of the field of water resources engineering and related disciplines.

Graduate research and projects in the HSE program typically consider topics such as:

• Drought characterization and prediction
• Ecological implications of hydrologic processes
• Energy balance of the land surface
• Evaporation from water bodies and soils
• Flood prediction and flood forecasting
• Geographical Information System (GIS) application
• Hydrologic effects of climate change
• Hydrologic impacts of large-scale atmospheric and oceanic interactions such as ENSO and PDO
• Hydroclimatology and hydrometeorology
• Human impacts on hydrologic processes
• Infrastructure responses to hydrologic processes
• Land-ocean-atmosphere interactions
• Numerical modeling of hydrologic systems
• Rainfall-runoff modeling of watersheds and river basins
• Reconstruction of precipitation and streamflow based on tree ring indices
• Risk and uncertainty analysis of water resources systems
• River network properties and dynamics
• River basin morphology and evolution
• Runoff and storm flows
• Spatial variability: analysis and simulation
• Scale effects and scaling invariance
• Soil moisture patterns and dynamics
• Stochastic analysis, modeling, and simulation of hydrological processes
• Temporal dynamics: analysis and simulation
• Transpiration from vegetation
• Water supply planning
• Water quality and hydrologic processes
• Watershed erosion and sedimentation

Research

Rainfall fields generated by a multifractal model on a small watershed of ARS experimental site of the Lindstrom farm near Sterling, Colorado

The HSE faculty members have broad research interests.  These include:  stochastic characterization and simulation of hydrologic processes, prediction of extreme events, hydrometeorology, hydroclimatology, scaling analysis, watershed erosion and morphology, river basin modeling, and soil moisture patterns and variability. 

Research on stochastic hydrology has been an active area at Colorado State University for several decades.  Examples include:  the characterization of the temporal and spatial variability of hydrological processes such as precipitation and streamflow, the stochastic modeling of precipitation and streamflow at various time scales  (e.g. hourly, daily, monthly, and yearly), the development of stochastic modeling schemes for large-scale complex river systems, the formulation and application of stochastic models capable of representing abrupt changes and non-stationarity, the development of statistical procedures for estimating quantiles of extreme precipitation and extreme floods, the characterization of drought dynamics based on probabilistic methods, and the development of methods for record extension and reconstruction of streamflows based on tree ring indices.  In addition, specialized software has been developed such as SAMS that is capable of analyzing, modeling, and simulating streamflow at single and multiple sites including the effects of abrupt climate shifts.  Furthermore, many of the models, procedures, and software tools developed in our research program have been applied by Federal and local agencies and consulting firms in the United States and elsewhere to tackle engineering problems.

Research on hydrometeorology focuses on hydrologic processes that occur at the interface of the atmosphere and the land surface such as evapotranspiration and soil moisture dynamics.  Ongoing research is considering the complementary relationship between evaporation and potential evaporation.

A so-called "parallel" river network, which exhibits distinctive fractal characteristics.

Another active area of research has been river basin morphology.  Research in this area focuses on the interaction between hydrologic processes and the land surface.  At short time scales, river basin topography can influence the space-time patterns of soil moisture, runoff production, and evapotranspiration.

Examples of research in this area include:  assessments of topographic controls on soil moisture patterns and dynamics, interpolation and downscaling of soil moisture observations using topographic information, and estimation of evapotranspiration rates from sites with varying water table depths using remote sensing. At long time scales, runoff and streamflow shape the basin through erosion and sedimentation processes.  Examples of research topics at this time scale are:  assessments of fractal and scaling-invariant properties of river basin topography, improvement of models to simulate long-term erosion and sedimentation in watersheds, analysis of the intrinsic variability of geomorphic processes, characterization of feedbacks between hydrologic and geomorphic processes.

Research on river basin modeling includes the mathematical modeling of the various components of the hydrological cycle of river basins based on physical and conceptual equations and relationships.  Examples include water balance models at the climatic, annual, and seasonal time scales such as SEAMOD and more complete models developed for smaller time scales, such as HIRO2.

The HSE program advocates the active participation of graduate students in publishing research results in refereed journals, proceedings, books, and digital media.  We also encourage and help students to make presentations at professional conferences, workshops, symposia, etc.  Examples of HSE publications can be found at the Hydrology Days Proceedings.

Faculty & Staff

The following faculty are core members of the Hydrologic Science and Engineering program:

Jeffrey D. Niemann, Faoro Assistant Professor
Jorge A. Ramirez, Professor and Program Coordinator
Jose D. Salas, Professor

Collaborating faculty from the Civil and Environmental Engineering Department include:

Deanna Durnford, Professor
Luis Garcia, Professor and Department Head
Timothy Green, Faculty Affiliate
Neil Grigg, Professor
Pierre Julien, Professor
Jim Loftis, Professor
Larry Roesner, Professor
Thomas Sanders, Associate Professor
James Warner, Associate Professor

Facilities and Resources

The HSE program has excellent resources that enhance graduate studies and research.  Graduate students in this program have office space in the Hydrology and Water Resources Computing Laboratory in the Engineering building.  In this laboratory, students have access to state-of-the-art computing facilities for numerical modeling and data analysis.  They can also readily access Colorado State University’s extensive online collection of journal publications.  Additional computing resources are available from Engineering Network Services, which maintains several computer laboratories in the Engineering building as well as centralized networks and grids of workstations for parallel programming applications and computationally intensive procedures.  The Hydrology and Water Resources Computing Laboratory is also in close proximity to the university library, faculty offices, the student center, and classrooms.

Additional office and laboratory facilities are available at the Engineering Research Center (ERC) on the Foothills Research Campus of Colorado State University.  This site houses outstanding experimental facilities including numerous large flumes, which are also available to graduate students and researchers in the program.  For example, the Rainfall Erosion Facility (REF) offers a controlled environment to study erosion processes at the watershed scale.  An outdoor hydrologic observatory is also under development at a watershed near campus.

The HSE program also benefits from the Borland Endowment to the Civil and Environmental Engineering Department. This endowment supports faculty research, equipment grants to department faculty, as well as scholarships to current and prospective graduate students in hydrology and water resources.

The Hydrology Days Conference, which is co-sponsored by the American Geophysical Union, occurs annually on the CSU campus.  This conference draws researchers from around the world to present their most exciting results in the field of hydrology and related fields in water resources.  The conference also hosts the Hydrology Days Award lecture and the Borland Lecture in Hydrology, which honor leaders in hydrologic research and practice.

The HSE program benefits from Colorado State University's broad expertise in water-related issues. More than 100 faculty members on campus conduct research related to water, which provides numerous opportunities for collaboration as well as a broad selection of courses for students.  Furthermore, a number of Federal agencies such as the Agriculture Research Service, the National Park Service, the Rocky Mountain Forest and Range Experiment Station, and the U.S. Geological Survey have offices and research facilities at or near Colorado State University campus, which also enhances collaboration by graduate students and faculty of the program.

Courses

In the HSE program, students select their courses (in consultation with their advisor) to match their specific interests and needs.  No specific courses are required at the masters or doctoral level, which allows each student maximum flexibility to tailor their education to their interests.  Typically, students take courses in hydrology, fluid mechanics, hydraulics, and water resources planning and management.  Students also commonly take courses in other disciplines such as atmospheric science, ecosystem science, geoscience, soil science, mathematics, statistics, and economics.

One possible program of study for a Master of Science student is shown below:

One possible program of study for a Ph.D. student is shown below:

Courses that are commonly taken by students in the HSE program include:

PhD Qualifying Exam

The PhD qualifying exam in the HSE program is administered by the student’s PhD thesis committee (the student’s advisor, two faculty members from the Civil and Environmental Engineering Department, and one faculty member from another department).  Each committee member submits 2 to 3 questions to the student’s advisor in advance of the exam.  The student is allowed 2 hours to review the submitted questions and prepare answers using any available written materials.  Immediately after the 2 hour period, the student meets with the thesis committee to answer these and other related questions orally.