then is programmed into the system so that it
handling facilities are an important adjunct to
can be operated from the lock control room.
this project and the others visited in the North-
Many new tasks were added to the system since
west. Navigation is very important also, but in
the original design and since the project went
terms of man-hours to operate and maintain the
into operation in the late 1980s.
facility, navigation is a secondary activity.
The central computer system has a master
The tour of the project was conducted by the
program known as a "ladder-and-rung" type,
chief of maintenance and the chief of tech ser-
with about 1100 rungs. In this program, any de-
vices/contract services. From the standpoint of
sired sequence of processes or operations can be
navigation, very little automation exists at this
arranged. Also, "interlocks," or steps that can
project. The tainter gates of the dam are auto-
proceed only after some particular condition is
mated as part of the overall hydroelectric con-
met (e.g., other devices open, closed, on, off),
trol system, a highly automated system (net-
can be chosen as desired and incorporated into
worked with other projects in the Columbia Ba-
any part of the program. Any conceivable vari-
sin) that was at the time undergoing complete
ety of operational procedures thus can be
upgrading. Readout of tainter gate position is
achieved with a few minutes of software revi-
available in the hydroelectric control room, and
sion, either at the lock or at the District office,
remote operation from the control room is cus-
and either by qualified local lock personnel or
tomary. Preprogrammed sequencing and coor-
by an appropriate engineer at the District.
dination of gate operation is theoretically possi-
The automated control system for Melvin
ble, as is remote operation from the McNary
Price L&D was designed and specified by St.
Project at Umatilla, Oregon, or the Bonneville
Louis District personnel. No outside consultant
Power Administration's control center in Van-
was used. In a few instances the contractor sub-
couver, Washington, but none of this is done,
stituted inferior equipment (encoders, cards,
mainly as a matter of policy.
switches, etc.), most of which have failed and
Lock operation is done from the lock stands,
been replaced with better equipment.
and is largely manual/visual. For the most part
There is no users' manual. The lock operators
the lock components are operated by means of
need to learn very little. The main burden of the
electromechanical, relay-based systems. Along
system falls on the programmers--they have to
with a lift of 103 feet, a noteworthy feature of the
be sure all operations are sequenced and inter-
Ice Harbor lock is the lower gate, a "guillotine"
locked appropriately.
or vertical lift gate of very substantial size and
St. Louis District personnel strongly believe
weight. (This type of lower lock gate is also
that developing a system such as that at Melvin
present at the Lower Monumental Project, just
Price with the use of an outside consultant is not
upstream on the Snake River, and at the John
likely to give satisfactory results. This would be
Day Project on the Columbia River.) The gate
especially true if the consultant is primarily an
poses several operational problems, one of
expert in the electronics of process control. What
which is controlling skew. This kind of problem
is essential, they believe, is that the designer,
is quite amenable to a fairly simple automated
and especially the programmer, be intimately fa-
monitoring and control system, but at present
miliar with the details of lock and dam opera-
the operators must watch a readout giving skew
tions, the hazards, and the rationales that govern
indication, and make manual corrections in op-
operations under all river and seasonal condi-
erating the separate left and right lifting machin-
tions.
ery. Operator inattention is covered by limit set-
tings for skew values, which if exceeded will re-
sult in shutdown of gate movement.
Ice Harbor Project, Pasco, Washington
On 7 January 1992, the Ice Harbor Project was
The upper lock gate is a tainter gate. This gate
visited. This is Walla Walla District's most
also is subject to skew during movement, but it
downstream hydroelectric and navigation dam
is generally not a serious difficulty.
on the Snake River. It is also the oldest project
On the same day that Ice Harbor was visited, a
on the Snake, having been opened to navigation
brief stop was made at the Lower Monumental
in 1962. As with all of the Walla Walla District
Project, which is also under the supervision of the
and Portland District projects visited during Jan-
Project Manager located at Ice Harbor. Lower
uary 1992, hydroelectric generation is the domi-
Monumental is 32 miles upstream from Ice Har-
nant activity at this installation. In addition, fish-
bor. This project is nearly as old as Ice Harbor,
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