and the level of automation is substantially the
at McNary is heavily automated. McNary serves
same.
as the central control facility for all power genera-
tion in the District, although its capability to actu-
ally remotely operate the upstream Walla Walla
Lower Granite Project, Pomeroy, Washington
This project, visited on 8 January 1992, is Wal-
District projects is not extensively employed.
la Walla District's most upstream dam on the
Snake River, being about 97 miles above Ice Har-
John Day Project, Rufus, Oregon
bor and 30 miles downstream from Lewiston,
This project is the most upstream facility under
Idaho. It is also the newest project on the Snake
the jurisdiction of the Portland District. Naviga-
River, having opened to navigation in 1975. The
tion through the 113-foot-lift lock began in 1968.
inspection of this project was hosted by the chief
John Day was visited on 10 January 1992, under
of operations/maintenance and the chief of main-
the guidance of two powerplant control room
tenance engineering/contract services.
managers.
As with the Ice Harbor Project, the major pres-
The lower lock gate is of the guillotine type, as
ence of automation at Lower Granite is in the
is present at Ice Harbor and Lower Monumental
hydroelectric area. Although over a decade new-
Projects. The upper gate is a submergible vertical
er than Ice Harbor, the lock machinery operations
lift gate. The latter gate has been subject to acci-
are accomplished with traditional non-solid-state
dents that occur as follows: When a tow in a fill-
equipment, calling for conventional manual/vis-
ing pool is too close to the upper end of the cham-
ual operations.
ber, the prow of the lead barge strikes the gate's
The lower lock gates at Lower Granite are
superstructure from beneath. The most recent in-
miter gates. In spite of their large size (there is a
stance of this happening was in July 1990. The
105-foot lift here), they function well. The upper
gate was damaged beyond use, and lockages had
lock gate is a tainter, similar to that at Ice Harbor.
to be made using a floating bulkhead to effect an
upper closure. This continued for several months
until a convenient service outage could be sched-
McNary Project, Umatilla, Oregon
The McNary Project is on the Columbia River
uled for replacing the gate.
at Umatilla, Oregon, the most downstream
It is possible to visualize automation schemes
project in the Walla Walla District. It was visited
where this kind of incident could be guarded
on 9 January 1992, with the chief of technical
against. Such a scheme would include a means of
staff/contract administration conducting a tour
monitoring the precise location of a vessel or a
and handling inquiries.
tow in the chamber. As a practical matter, the Dis-
Navigation at McNary has been conducted
trict placed large concrete buttresses in contact
since 1953; it is an older project with very little
with the floor and the walls of the lock chamber at
automation involved in the lock operation. The
the upper end, preventing an upbound tow from
lift at McNary is 83 feet and is accomplished
stationing itself too far forward during lock fill-
using miter gates at both the upper and lower
ing.
ends of the lock.
The principal automation item, which has
The Dalles Project, The Dalles, Oregon
been in place for just a short time, is a PLC-based
This project is about 25 miles downstream from
system for operating the opening of the left and
John Day; it was opened for navigation in 1957
right filling valves. Prior to this installation, fill-
with a lift of 90 feet. The power plant superinten-
ing valve operation had to be watched closely by
dent coordinated this visit on 10 January 1992, as
the operator to balance the inflows from each
well as the visit to John Day on the same day.
side, and thus minimize hazardous cross-currents
Both projects are under the same supervisory
in the lock chamber. Now the openings and
team, based at The Dalles. The tour of the project
opening rates of the filling valves are monitored
was conducted by an operator.
and kept in balance automatically by the PLC.
The lower lock gate at The Dalles is a conven-
The operator simply has to initiate the filling op-
tional miter gate, while the upper gate is a sub-
eration, and the system manages the process ac-
mergible tainter gate. As at John Day, the lock
cording to a program that has been developed to
machinery operations are accomplished with con-
maintain balanced flows.
ventional non-solid-state equipment and manual/
As described previously for the other Walla
visual procedures. While all of the Columbia/
Walla District projects, hydroelectric production
Snake projects visited in January 1992 are large,
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