Jacob H. Douma
A:
The relatively low dams were constructed with concrete all the way across the river.
There were no particular problems with the spillway, crest gates, or outlet works. There
is a fairly good size navigation lock located at one end of the dam. One of the problems
we had was that when large spillway discharge occurred with the spillway gates operating,
high velocities in the downstream river channel made it difficult for vessels to approach
the lock. Design changes had to be made, such as extending the spillway stilling basin
wall on the lock side farther downstream or extending the lock approach channel and, in
some cases, moving it farther into the river bank away from the main river channel.
Usually, model tests were necessary to check the design.
All that was normally done at WES?
A:
That's right.
Now that was all remedial work though, wasn't it?
Yes, most of it, but I was involved with the design of one or two later navigation dams
and locks on the Arkansas-Red River project.
So some of the later ones would have picked up those solutions.
A:
Yes.
When I was talking to Vern
he said that the Arkansas project presented a lot of
problems for them because of the amount of sedimentation in that whole system.
A:
Yes.
When you designed things, how much did you account for sedimentation?
A:
The old spillway crests weren't very high. The most critical condition with respect to
sedimentation was assumed for hydraulic design. That occurred when the sediment level
upstream of the dam was at the same level as the spillway crest. This would result in the
smallest spillway discharge for any reservoir level. Vern was concerned about the
maximum height of the reservoir water levels for the maximum possible flood, because
of upstream flooding. He attempted to determine the actual sediment level in the
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