Krone Lectures on Sediment Transport

San Francisco Bay is a tidally-energetic estuary where clay muds are the dominant sediment building wetlands, depositing in channels and harbors, and responding to sea level rise since San Francisco Bay was most recently inundated about 8,000 years ago.  These sediments mainly come from the Central Valley and become cohesive when they encounter enough salinity in the western Delta.  This causes the cohesive sediments to flocculate into larger particles which then settle, deposit, erode, circulate, and redeposit where the tides and flow take them.

UC Davis Professor Ray Krone was a founder of the field of cohesive sediment transport in the 1960s, related to sedimentation, erosion, and management of clay sediments.  His approach is very fundamental, based on the physics, chemistry, and modeling of these processes.  His last course lectures from 1991, which were recorded, have been recently discovered, lightly edited, and are now posted on Youtube.

This playlist includes 18 UC Davis graduate course lectures on the fundamentals of cohesive sediment behavior and transport from 1991, plus one video of an overview lecture at the University of Idaho in 2000 on soil erosion processes.  These lectures present foundational principles, but are important for discussion and application to San Francisco Bay, which he studied his entire career.  The intended audience of the lectures were graduate students in environmental engineering.  There is math, physics, fluid mechanics, and chemistry. The Bay and Delta are a complex place, and these lectures illustrate how and why cohesive sediment transport processes are important for environmental, commercial, and recreational purposes.

For California’s Bay-Delta system, there have been advances beyond these lectures, mostly in applying these principles to coastal wetlands and the Delta’s ecology (Brown et al. 2024).  The ability to apply such understanding has been improved immeasurably by advances in hydrodynamic modeling (RMA 2021; MacWilliams et al. 2016).

Here is the playlist of topics:

About Dr. Ray Krone

Ray Krone’s education was delayed by WWII, where he served as a reconnaissance pilot in Europe and became a life-long pilot.  He studied sediment transport with Hans Einstein.  He was elected to both the National Academy of Engineering and the American Academy for the Advancement of Science for his fundamental contributions to understanding cohesive sediment transport based on physics, chemistry, and the modeling of these processes.  Ray insisted that each of his classes include a field trip, a few lucky field trips were in his Cessna pointing out patterns of sediment origins and movement over the Cache Creek basin.  His emphasis on field education continues to inspire UC Davis field trips in many courses. We hope these lectures communicate his thinking on cohesive sediment transport, as well as his organized approach to problems and communications. He always had great stories. 

His insights into the history of Engineering and Civil and Environmental Engineering at UC Davis as summarized in a 1999 interview https://video.ucdavis.edu/media/Ray+Krone/0_aq3a9o3p

Further Readings

Ray Krone lectures playlist: https://www.youtube.com/watch?v=PujjYMzMA3U&list=PLw3bQVmYPxIvGvVeic0ywkYRUjnWJxfEA

Also: https://fabianbombardelli.com/Ray_Krone.htm (original mp4 files)

Ray Krone’s writings: https://scholar.google.com/scholar?hl=en&as_sdt=0%2C5&q=Ray+Krone+cohesive+sediment&btnG=

Krone, R.B. (1972), A Field Study of Flocculation As a Factor In Estuarial Shoaling Processes, Technical Bulletin No. 19, Committee on Tidal Hydraulics, Corps of Engineers, U.S. Army.

Krone, R.B. (1979), Sedimentation in the San Francisco Bay System, Fifty-eighth Annual Meeting of the Pacific Division of the American Association for the Advancement of Science, San Francisco State University, San Francisco, California, June 12-16, 1977, published 1979.

More on cohesive sediment transport:

Mehta, A.J., E.J. Hayter, W.R. Parker, R.B. Krone, & A.M. Teeter, “Cohesive Sediment Transport. I: Process Description”, J. of Hydraulic Engineering, Vol. 115, No. 8, 1989, 

Mehta, A.J. et al. (1989), Cohesive Sediment Transport II: Application,” Journal of Hydraulic Engineering, Vol. 115, No. 8, August, 1989

More recent application of these fundamentals to California’s Bay-Delta system:

Brown, L.R., Ayers, D.E., Bergamaschi, B., Burau, J.R., Dailey, E.T., Downing, B., Downing-Kunz, M., Feyrer, F.V., Huntsman, B.M., Kraus, T., Morgan, T., Lacy, J.R., Parchaso, F., Ruhl, C.A., Stumpner, E., Stumpner, P., Thompson, J., and Young, M.J., 2024, Physics to fish—Understanding the factors that create and sustain native fish habitat in the San Francisco Estuary: U.S. Geological Survey Open-File Report 2023–1087, 150 p., https://doi.org/10.3133/ofr20231087. 

MacWilliams, M.L., Ateljevich, E.S., Monismith, S.G. and Enright, C., 2016. An overview of multi-dimensional models of the Sacramento–San Joaquin Delta. San Francisco Estuary and Watershed 33 Science, 14(4). http://dx.doi.org/10.15447/sfews.2016v14iss4art2

RMA 2021, RMA UnTRIM San Francisco Estuary Model Calibration Report, Resource Management Associates, Davis, CA.

Check out the original post at the California Water Blog.

About the Authors

Jay Lund is an emeritus professor of civil and environmental engineering and geography at UC Davis.  William Fleenor is a retired professional researcher at UC Davis’ Center for Watershed Sciences, and secured recordings of most of these lectures until the 2010s. 

Jamie Anderson is a Senior Engineer with the California Department of Water Resources, who retained class handouts and readings from the 1991 course.

William Fleenor is a retired Project Engineer with the Center for Watershed Sciences, who preserved these recordings.

Fabián Bombardelli is a professor of civil and environmental engineering at UC Davis.

Mike Deas made useful suggestions on an earlier draft.