I was there…
Stream Reaeration Modeling:
A Georgia Civil Engineering Research Breakthrough
(1968-1972)
The ability of a flowing stream to obtain oxygen from the
atmosphere, i.e., “reaeration capacity,” is the fundamental process by which
the stream is able to “purify itself.” Thus, accurate prediction of the reaeration capacity of a polluted
stream is the necessary basis for determining the required waste treatment for
discharges from waste treatment plants and other sources of discharge to
streams. Attempts to evaluate stream reaeration
date back to at least 1911, and research in this area intensified during the
1950s and 60s. In the late 60s none of the existing predictive methods were
capable of providing dependable predictions of stream reaeration.
This effort began a giant leap forward when, in 1966, Dr.
E.C. Tsivoglou, previously Director
of Technical Services and Research US Public Health Service at the Taft Center
in Cincinnati, joined the faculty in the School of Civil Engineering at Georgia Tech. While at the PHS, Dr. Tsivoglou initiated a
new approach to the direct measurement of reaeration rates. This approach was based on the use of a
gaseous tracer, krypton-85. At the time he arrived at Tech, this method was
based primarily on laboratory scale procedures. At Tech he teamed with a young assistant professor, Dr. J. R. Wallace, to
conduct a series of field experiments in rivers in the Atlanta area. The purpose of these
experiments was to determine the relationship between the reaeration rates
measured in the flowing streams and measureable hydraulic characteristics of
the rivers.
The Georgia Tech research
began in 1968 under a grant from the Federal Water Pollution Control Agency,
the predecessor agency to the USEPA. Three
Atlanta-area rivers, the Chattahoochee, the South, and the Flint,
were included in the studies along with one river in Maryland, the Patuxent. These studies incorporated a wide range of
hydraulic features, including waterfalls, rapids, shoals, and pools with flows
ranging from 5 to 3,000 cfs. As a result
of these studies, a new energy dissipation model was derived by which the
reaeration capacity of a stream is explained in terms of the rate of energy
dissipation, measured as the loss of water surface elevation divided by the
time of flow. For the first time it was
possible to reliably predict the reaeration capacities of our rivers and
streams. Grad student assistants who participated in this research included
Harold Reheis, Larry Neal and others. For more details of this work, see “E. C.
Tsivoglou and J. R. Wallace, Characteristics of Stream Reaeration Capacity,
EPA-R3-72-012, October 1972.”
Submitted by Dr. James R. Wallace, M.ASCE
I was there…
Stream Reaeration Modeling:
A Georgia Civil Engineering Research Breakthrough
(1968-1972)
The ability of a flowing stream to obtain oxygen from the
atmosphere, i.e., “reaeration capacity,” is the fundamental process by which
the stream is able to “purify itself.” Thus, accurate prediction of the reaeration capacity of a polluted
stream is the necessary basis for determining the required waste treatment for
discharges from waste treatment plants and other sources of discharge to
streams. Attempts to evaluate stream reaeration
date back to at least 1911, and research in this area intensified during the
1950s and 60s. In the late 60s none of the existing predictive methods were
capable of providing dependable predictions of stream reaeration.
This effort began a giant leap forward when, in 1966, Dr.
E.C. Tsivoglou, previously Director
of Technical Services and Research US Public Health Service at the Taft Center
in Cincinnati, joined the faculty in the School of Civil Engineering at Georgia Tech. While at the PHS, Dr. Tsivoglou initiated a
new approach to the direct measurement of reaeration rates. This approach was based on the use of a
gaseous tracer, krypton-85. At the time he arrived at Tech, this method was
based primarily on laboratory scale procedures. At Tech he teamed with a young assistant professor, Dr. J. R. Wallace, to
conduct a series of field experiments in rivers in the Atlanta area. The purpose of these
experiments was to determine the relationship between the reaeration rates
measured in the flowing streams and measureable hydraulic characteristics of
the rivers.
The Georgia Tech research
began in 1968 under a grant from the Federal Water Pollution Control Agency,
the predecessor agency to the USEPA. Three
Atlanta-area rivers, the Chattahoochee, the South, and the Flint,
were included in the studies along with one river in Maryland, the Patuxent. These studies incorporated a wide range of
hydraulic features, including waterfalls, rapids, shoals, and pools with flows
ranging from 5 to 3,000 cfs. As a result
of these studies, a new energy dissipation model was derived by which the
reaeration capacity of a stream is explained in terms of the rate of energy
dissipation, measured as the loss of water surface elevation divided by the
time of flow. For the first time it was
possible to reliably predict the reaeration capacities of our rivers and
streams. Grad student assistants who participated in this research included
Harold Reheis, Larry Neal and others. For more details of this work, see “E. C.
Tsivoglou and J. R. Wallace, Characteristics of Stream Reaeration Capacity,
EPA-R3-72-012, October 1972.”
Submitted by Dr. James R. Wallace, M.ASCE