Print version of chapter
The first time John Goodier saw the Tuolumne
River canyon in which his company was to build
New Don Pedro Dam, he figured it would be "a tough
nut to crack."
"In construction and particularly at Guy F. Atkinson
we like the tough ones. That’s where we make our
living and the tougher they are, the better we
like it," Goodier said, noting his firm had built
some of the world’s largest dams.
Goodier, who was Atkinson’s project superintendent
on the job in 1967, explained the main problems
were the river, which he described as "violent,"
the terrain, and the heat, which was so severe
that cement workers had to mix concrete with ice
instead of water to keep it cool enough to work.
The dam was to be located in a V-shaped gorge
with side slopes of up to 40 per cent. Access
to the bottom of the gorge would be "very, very
difficult." During early core exploration and
surveys in 1961 the only access to much of the
canyon was achieved by filling a hundred-year
old canal perched on the side of the hill. Barely
a Jeep’s width, the outer wall built by Chinese
laborers proved just as solid and secure as it
had been a century earlier.
Later, after Goodier had become vice president
and chief engineer of Guy F. Atkinson Company,
he summarized his view of the project:
It was an interesting job for a
contractor. We started building access roads to
the dam site. We did everything. It had many construction
features to it: two tunnels, a shaft, a powerhouse,
a switchyard, a dam and a spillway all in one
job. When we left the job, it was 100 percent
complete. You like to watch a project like this
develop. The terrain was rugged, but it was a
nice area to live in and it was a very good assignment.
Guy F. Atkinson had been awarded a $49,693,960
prime construction contract - $3.7 million under
Bechtel’s engineering estimate on August 22,
1967. This figure set the total project cost at
less than the $105 million estimate made May 23,
1966, when the Modesto and Turlock Irrigation
Districts and the City of San Francisco formally
entered into the "fourth agreement" to proceed
on New Don Pedro.
The day after bids were opened, June 22, 1967,
Atkinson started mobilizing equipment in anticipation
of receiving the contract.
Formal notice to proceed had to await the California
Districts Securities Commission’s approval of
the sale of the bonds which would fund the project.
This came June 30th. Also needed was
the issuance of a California Division of Dam Safety
license, granted on July 6th. The Bank
of America purchased the Modesto and Turlock Irrigation
Districts’ bonds totaling $46.5 million on August
1st at 4.12 percent interest. San Francisco’s
$45 million in bonds were purchased the same day
by a group of Eastern banks for 3.8 per cent interest.
More than a month before the formal award of
contract and issuance of the notice to proceed,
the contractor and issuance of the notice to proceed,
the contractor began construction of the access
road to the upstream portal of the Tuolumne River
diversion tunnel. Atkinson shared the districts’
desire to expedite work after years of waiting
for the Federal Power Commission license to be
The irrigation districts did not discourage this
enthusiasm. On their own part, eight months before
the project was to proceed, they awarded contracts
for the manufacture of powerhouse turbines, generators
and other equipment. Turbines and generators are
not "on the shelf" inventory items and must be
built to individual specifications.
Contracts were awarded to three Japanese firms
Mitsubishi, $1,304,878, for the turbines; Mitsui,
$1,163,530, for the generators, and Hitachi, $213,820,
for the crane on the basis that the manufacturers
would proceed only with working drawings. They
were not to build the equipment until notified
that the project would proceed. A $310,352 transformer
contract was signed with Savigliano of Italy on
the same basis. Had the project not gone ahead,
the districts were liable for the $90,000 cost
of working-drawings. The four bids were $1.4 million
below engineers’ estimates.
In this way, the districts got a full year’s
jump on completion of the project.
By the time the formal notice to proceed was
issued on August 22nd, Atkinson had
gathered much of its equipment, ordered massive
earth movers, established a field office, built
a trailer camp for construction workers and their
families, started clearing the dam site, begun
work on the spillway high on the north bank of
the Tuolumne and was building access roads.
From June 1967 until June 21, 1971, when the
last of Atkinson’s forces left the field, the
canyon was a beehive of noise and activity, except
for one brief moment September 16, 1968. Work
was halted at that time in tribute to company
founder Guy F. Atkinson, 93, who died four days
earlier. Since staring his construction business
in 1901, Atkinson had built a variety of projects,
including Mangla Dam in West Pakistan, the world’s
largest hydroelectric project, more than 10 times
the size of New Don Pedro; Grand Coulee Dam on
the Columbia River, the largest concrete dam in
the world; Trinity Dam, a Bureau of Reclamation
project in Northern California, and Hetch Hetchy’s
Cherry Valley Dam.
In a separate contract, the districts awarded
Trico Contractors of Merced the task of clearing
the reservoir site, which ultimately meant cleaning
6,300 acres of land at a cost of more than $888,000.
Trico went to work October 3rd.
MID Board President Thomas Beard, TID Board President
E. L. Tomlinson and San Francisco Public Utilities
Chairman Thomas White shared the honors as they
set off a dynamite blast to mark the ceremonial
start of the project.
Memorialized at the ceremony were three men active
in moving the project ahead but who had not lived
to see its start: James Smith, MID board president
at the time of his death in 1966; Abner Crowell,
who served for many years as TID board president
prior to his death a short time earlier, and Robert
Kirkwood, manager of San Francisco utilities form
1959 to 1964.
Irrigation Engineer Charles Crawford, who had
been with the Modesto Irrigation District for
39 years, was named project coordinator, representing
the three partners on the river. Charles S. Rippon,
a veteran U. S. Bureau of Reclamation engineer,
was named assistant.
Before work could be started on the dam proper,
a diversion tunnel had to be built and the 1,267-acre
dam site cleared.
Excavation of the 3,415-foot long, 30-foot diameter
tunnel was started at the upstream end on September
27, 1967. The bore was 32.5 in diameter, providing
room for 2.5 feet of concrete lining. Work was
stepped up to three shifts daily, six days a week,
upon completion of a bridge across a river on
October 12th. Drilling from the downstream
end began on January 11, 1968.
With crews working from both ends and driving
an average of 29.7 lineal feet a day, the tunnel
was "holed through" in perfect alignment of March
13th and was ready for lining on April
15th. In less than seven months the
drilling teams had blasted and hauled out of the
tunnel 106,934 cubic yards of rock and earth.
As a safety precaution, Bechtel’s designers insisted
upon overhead steel mesh to protect miners from
loose rock, walnut sized or smaller. The safety
net was resisted at first by the independent-minded
miners, who were used to prying off loose rock
themselves. After the first 500 feet of boring,
they accepted the safety measure as expediting
work. While earplugs for miners also were required,
many refused to wear them. Deafness was the trademark
of old-time tunnel workers.
A revolutionary 40-foot long retractable form
made in the shape of the full diameter of the
tunnel and operated on a 92-foot long steel-beam
traveler applied the concrete lining. The rig
even had special vibrators for tamping and compacting
the mixed cement. With pour rates of 70 yards
per hour, 20.8 feet of lining was completed each
The long concrete and steel-lined tunnel was
completed in August and on September 5th
TID Chief Engineer Roy V. Meikle set off a blast
of 1,200 pounds of explosives to blow away a rock
plug. The huge tunnel was ready for the river.
The following day, releases from "old" Don Pedro
were halted and a 40-foot high, 160-foot long
coffer dam was thrown across the river. Diversions
of the water was started September 7th.
While the diversion tunnel was being bored, the
work of exposing the foundation rock for the dam
proceeded so that construction could commence
as soon as the river was diverted. Rock that could
not be moved by the immense power of a D-9 Caterpillar
dozer was considered stable.
Nine days after the river was diverted, the first
load of dredge tailings which were to form the
outer shell of the upstream side of New Don Pedro
was placed. Fire hoses were used to sluice the
material down around the dam’s bedrock foundation.
Thus, New Don Pedro began its steady rise toward
its ultimate height of 585 feet.
Near disaster struck on January 26, 1969, when
floodwaters surged over the "old" Don Pedro spillway,
unleashing more than 41,000 cubic feet of water
per second, more than three times the capacity
of the diversion tunnel. The top 15 feet of the
40-foot coffer dam and the project’s bridges were
washed out. The streambed was covered with 35
feet of water, which left in its wake 15 feet
of silt in the previously cleaned core area.
"We lost the bridges about midnight," Goodier
recalled. "It was pouring down rain and it was
dark. Up river, it really was roaring. There’s
nothing more dynamic than an angry river."
A full month behind schedule because of the flood,
the contractor was running against a deadline
which if unmet would mean the loss of a construction
season. That in turn would mean a year’s delay
in completion. There was nothing to do but to
clean up and rebuild. The deadline was made with
a week to spare. Work was back on schedule by
Atkinson met every deadline on raising the dam.
The company cut one deadline close, a single day.
Goodier explained, "We did work the previous Saturday
and could have worked a couple of Sundays but
we didn’t like to work weekends. Not only because
of the added overtime, but in that hot canyon
working seven days affected the men’s work efficiency
throughout the subsequent week."
With the river diverted, virtually no excavation
was needed under the center of the dam. The river’s
hard bedrock was "broomed and washed" absolutely
clean. Cracks and holes were filled with "dental
concrete," so-called because it was used in much
the same manner as when a dentist fills a tooth.
Some of these cavities were rather large, though.
Consolidation grouting extended 25 feet below
the dam’s impervious core and concrete curtain
grouting was placed 200 feet under the center
of the streambed. On February 27, 1969, the first
of the impervious material which was to form the
dam’s core was placed. Ultimately the core was
to be 280 feet wide.
Averaging 18 inches a day, the dam rose higher
and higher for the next 15 months. Tower floodlights
turned night into day and permitted three work
shifts to maintain the rapid pace.
A fleet of 40 specially-built 125-ton trucks
hauled materials which had been unearthed by the
turn-of-the-century gold dredges. Nicknamed "belly
dumps," these earth movers were mechanical marvels,
the biggest trucks in the world at the time.
Powered by 750-horsepower V-16 diesel engines,
they ran back and forth along a private 60-foot
wide, 13-mile long specially-built haul road,
delivering 75 yards of material to the dam every
two or three minutes. Computer analysis had established
that the most efficient highway grade was a constant
2.93 percent. The highway and the trucks’ automatic
transmissions were built accordingly.
Each truck cost about $165,000, as did each of
four huge scoop rigs built especially to load
them. Each truck carried 400 gallons of fuel,
which lasted about 15 hours. When the fuel gauge
indicated 25 gallons were left, the driver would
radio ahead to the fuel depot to be ready for
him. As he approached the "pit stop," he drove
through an automatic truck washer. In five to
15 minutes, the earth mover would be fueled, checked,
washed, serviced and back on the road.
Washing was essential at each fueling because
on the dirt roads the buildup of mud would reach
5,000 pounds if trucks were not washed regularly.
The rigs operated around the clock from 8 AM
Mondays to 8 PM Saturdays, stopping only for a
half-hour lunch period on each shift. At the change
in shifts, the new driver would meet his assigned
truck at "Checkpoint Charlie," take his lunch
and two-gallon water jug supplied by the contractor,
mount his rig and "hit the road." Routine maintenance
was performed on weekends. In 15 months, the rigs
were idled only 65 shifts due to bad weather.
Dust was a constant problem as the huge trucks
plowed uphill at 15 miles an hour and sped down
empty at 45. Roads had to be watered constantly.
The one-on-the-job fatality during the project
was Modestan Emzy Herman Hoeppner, 30, who was
killed when thrown from his 6,000-gallon water
truck as it plunged off a 65-foot embankment on
the powerhouse access road.
In their 24-hour-a-day parade up and down the
canyon wall month after month, the giant earth
movers were involved in but three accidents. In
each case, the behemoths backed over parked pickup
trucks, flattening them.
The 6-foot, 4-inch diameter tires proved to be
the weakest link in maintenance of the earth movers.
They were so huge they had to be made by hand
and never were quite perfect. They kept separating,
especially in hot weather. Each tire cost $5,000.
Keeping the tires cool was as important as settling
the dust. On much of the haul road, automatic
sprinklers were installed along each side of the
road, timed electrically so they would kick on
a fifth of the system at a time for 10-minute
intervals. These and the world’s biggest road
graders kept the road smooth and dust-free.
They also provided some amusement at the expense
of guests of the handful of supervisory personnel
who were allowed on the haul road.
"Driving down the road in the middle of August
with the temperature at 105, the sprinklers would
come on," Goodier explained. "The driver, of course,
would be near the middle of the road, but the
passenger, who had his window down, would be near
the edge and wouldn’t know what hit him when that
cold water just shot right out of the side of
Rainbird sprinklers at 60-foot intervals saved
approximately $100,000 compared with the cost
of water trucks.
Silty sand mixed with clay found near La Grange
was used for the core of the dam.
Tailings which had been worked over only once
by the dredges contained enough "fines" ’ sand
and small gravel ’ so that they were suitable
for transition materials. Tailings which twice
had been used in the dredges’ quest for gold were
coarse enough for the shells, which also contained
material excavated from tunnels, spillways and
abutments. It is the thick layers of coarse rock,
called shells, on each side of the dam that give
the structure its strength.
Two years after work began, there were 500 men
on the job. The project as a whole was 53 percent
complete and the dam, now 280 feet high, was 40
percent finished. The spillways were nearly completed.
Sonora Union Democrat reporter Mark Kautz
referred to the "Towering Temples on the Tuolumne"
in comparing the awesome works of man in building
the mammoth project with mysterious Stonehenge
and the Egyptian pyramids of ancient times.
On May 28, 1970, Modestan George Koetsky wheeled
his 125-ton earth mover across the dam with TID
Chief Engineer Meikle riding "shotgun," to deliver
the last load of material. "Topping out" ceremonies
marked the completion of the dam proper. More
than 250,000 trips had been made to deliver the
16,314,000 yards of material required by the dam
The structure has three ways of controlling flood
flows. One, and possibly two, of these probably
never will be needed.
Internal gates installed in the diversion tunnel
allow the release of 7,370 cubic feet per second
of water, in addition to the 4,100 second feet
maximum flow that can be released through the
powerhouse turbines and 3,100 second feet through
a hollow jet valve.
When these gates were installed in March 1971,
Crawford expressed the hope that most if not all
floods would be controlled through the power releases
and the diversion tunnel gates. When flows hit
9,500 second feet at La Grange, minor downstream
flooding does occur.
The controlled spillway, construction of which
began August 29, 1967, just one week after Atkinson
was issued a notice to proceed, was completed
December 10, 1969, five months before the dam
was "topped out." This spillway was designed to
handle flood flows of up to 172,000 cubic feet
of water per second. Although the Army Engineers
indicated flows of this magnitude might be expected
once every 44 years, this volume of floodwater
approximates that of the worst flood in recorded
history. The Tuolumne River flood of December
1955 would have attained this magnitude had there
been no dams on the river. As it was, existing
dams checked the flow below La Grange to less
than a fourth of that.
Three steel, radial spillway gates, each 45 feet
wide, 30 feet tall and weighing 135,000 pounds,
were manufactured in Japan by Kurimosto Iron Works
at a cost of $233,750. They are installed at the
head of a 136.5-foot rectangular, reinforced concrete
discharge chute anchored horizontally and vertically
by 20-and 30-foot-long rock bolts.
The last concrete had been poured on the emergency
spillway near the crest of the dam on January
19, 1969. The massive concrete structure, 995
feet long and 26.4 feet wide, is anchored to bedrock
by hundreds of 10- and 20-foot-long rock bolts.
Designed to handle 300,000 cubic feet of runoff,
the emergency spillway will be needed only in
the most dramatic of floods, if ever.
Crawford commented, "If the flood for which the
emergency spillway is designed ever happens, the
Valley will be something else. With all the rivers
in flood, the Valley will be a lake again."
Although "topping out" marked completion of the
dam itself, final cleanup still was a year away.
Water could not be stored behind the structure
until two important tasks had been completed:
clearing the reservoir site and relocating roads
Reservoir clearing was started on October 3,
1967. Before it was finished on March 31, 1971,
nearly 7,000 acres of land had been stripped of
trees, brush, stumps, utility poles, driftwood,
fences, buildings, anything that would float.
Everything had been burned and the ashes buried.
Only patches of brush designated by California
Division of Fish and Game representatives were
left to encourage the propagation of fish. Trico
Contractors also had to remove an abandoned Hetch
Hetchy Railroad bridge to improve boating safety.
Anything man-made was hauled away or buried.
Old mine shafts were located. Concrete seals
were placed in the bottom of the shafts, which
then were filled with dirt. Thick concrete caps
were placed on entrances to the shafts. The reservoir
must be as water tight as the dam.
To clear steep hillsides, especially in the vicinity
of the Hetch Hetchy Aqueduct siphon at Red Mountain
Bar, the ingenious Trico workers adopted the "yo-yo"
system. One huge dozer was stationed firmly at
the top of the hill and a second dozer was winched
up and down the steep incline to do the actual
While spectacular to watch, the "yo-yo" proved
not too hazardous. Only once did a "Cat" at the
end of the line come loose. The huge tractor rolled
over six times on the way down the steep hill,
but the driver, protected by roll bars, walked
away, shaken but virtually unscathed.
When the job was finished, the reservoir not
only was cleared but also had a 160-mile fire-break-two-dozer
blades wide around the entire site at elevation
830 feet above sea level.
Started before, 1960, the discussions on the
relocation of roads were to drag on until the
last minute, involving exhaustive negotiations
with Tuolumne County and the California Division
of Highways. In 1962 the MID found itself involved
in a dispute as to whether the Highways 49-120
route should be rebuilt on the north or south
side of the new reservoir.
A majority of Tuolumne County residents favored
the north routing, but a vocal majority, sparked
by people in the Wards Ferry area, preferred the
south side. Because the southern route would be
more expensive, require an extra bridge and mean
a longer drive for Northern Californians headed
for Yosemite, the districts argued for the northern
route, but they lost. CalTrans insisted the southern
route would be more convenient for its future
plans to relocate the Highway 120 route to Yosemite.
One of Crawford’s first actions after being appointed
project coordinator in 1967 was to meet with the
Highway 120 Association in Tuolumne County to
discuss rerouting the Mother Lode highway, which
ran through Jacksonville, and the acquisition
of the town. This historic community dated from
1848, when Colonel Alden Apollo Moore Jackson,
a miner turned merchant, set up a supply and amusement
center in a tent for the miners along nearby Moccasin
and Woods Creeks.
In August 1967 Tuolumne County signed a freeway
agreement with the state providing for the relocation
of the Highways 49-120 route in the Chinese Camp
and Jacksonville areas. The county had held up
the agreement for two years to insure that funds
for the $2.5 million, 8-mile realignment were
not charged against the county’s annual allocation
of $1 million in state highway funds.
After seven years of discussions, the districts
and the California State Division of Highways
reached agreement in March 1968, allowing the
state to proceed with relocations and providing
for payment by the project. The districts paid
only for the replacement of highways "in kind,"
with any improvements financed by the state. The
districts also agreed to pay "extraordinary" maintenance
costs which the state might face on the new routes
during the first three years of operation. Implementation
of this provision was never required.
Bridges were a jinx for the project.
Weak steel was discovered in the Jacksonville
Bridge after the failure of a Sacramento area
bridge which had been built with steel from the
same supplier. Replacement of the steel delayed
construction for four months. The realigned route
was not opened until April 1971, less than two
weeks before the water backing up behind New Don
Pedro Dam flooded the old bridge.
The districts paid contractor Peter Kewitt &
Son an additional $55,000 to go to a 10-hour seven-day-week
schedule to complete work early enough to catch
the spring river runoff in a slightly below-normal
water season. This move saved for storage an additional
390,000 acre feet of water.
Among the other historic landmarks which would
be inundated by the reservoir was the Wards Ferry
Bridge 12 miles east of Sonora. The original span
dated to 1878 when citizens personally donated
the funds to build it. It was destroyed by fire
13 years later to hide the robbery and murder
of two bridge tenders. Six years later, Tuolumne
County replaced it with a 173-foot steel span.
It wasn’t until December 1968 that the districts
agreed to construct a new bridge at Wards Ferry.
This was part of a lengthy compact between the
mountain county and the two Valley irrigation
districts which also included the construction
of a bridge at Stevens Bar, relocation of River
Road and provision of five turnarounds on roads
which would dead-end at the reservoir’s edge.
A 10-ton crane overturned after work finally
got under way on the Wards Ferry Bridge in January
1971 and damaged the nearly completed deck. This
accident forced considerable reconstruction and
the bridge, one of the last to be completed, was
not opened to the traffic until August 1972.
In the meantime, on May 18, 1971, the tired old
Wards Ferry Bridge collapsed while the contractor
was blasting near the right abutment of the new
Major problems were experienced also in the construction
of the 1,441-foot Stevens Bar Bridge on the Jacksonville-Stent
Road near Moccasin Creek. Continuous slides in
the steep cuts on the bridge approaches caused
the loss of 73 work days.
The Moccasin Bridge suffered less serious problems
with cracking bearing pads. Difficulties were
overcome and the route was opened November 25,
1970, but not until the districts had agreed to
accept the responsibility for extraordinary maintenance
for a period of five years. No serious problems
developed during that period, however. Careful
monitoring over a 10-year period showed this problem
had not weakened the structure.
The new dam was ready to store water on November
2, 1970, and the portals of the old Don Pedro
Dam were opened for the last time to release water
Water edged up the face of New Don Pedro Dam
rapidly at first, reaching the 250-foot mark within
24 hours. As the water then rose more slowly but
steadily, it climbed the upstream face of the
old concrete dam which in 1923 had been the tallest
such structure in the world.
Old Don Pedro disappeared under the surface of
Don Pedro Lake on April 12, 1970, and was not
visible again for six-and-a-half years. It reappeared
in 1977 when the reservoir level was drawn down
during the drought.
The water lapped over the historic town of Jacksonville
in June 1970. Ultimately, the community, lively
in the gold rush days, would be under 200 feet
of water. The John Terry family, the last to depart,
was typical of those forced to move, waiting until
the last possible minute.
Land acquisition is never an easy task in large
public works projects. New Don Pedro was no exception.
Old-time residents fought the districts all the
way. For instance, John Turner, who operated the
Taco House restaurant on an unpatented mining
claim at Moccasin, called irrigation district
representatives "worse than rattlesnakes." Claiming
he knew because as a youth he was a professional
snake hunter in Mexico and Guatemala, the 73-year-old
Turner said rattlers warn before they struck.
Crawford, identifying himself "as one of the rattlesnakes,"
countered by noting that Turner, who did not own
the land on which he operated his restaurant,
had known about the project for five years.
Land acquisition condemnation trials and negotiations
were to continue long after the reservoir was
A critical element of the entire project, especially
as far as paying for it is concerned, is the hydroelectric
generating facilities. Called for was an outdoor
powerhouse with three generators capable of producing
an average output of 638 million kilowatt hours
of electricity annually.
Excavation of the 2,890-foot long power tunnel
tapering in diameter from 18.5 feet at the upstream
end to 16 feet downstream began on April 1, 1968.
It was completed in 51 weeks, the most difficult
part being the downstream section. Approximately
one-third of the tunnel is flat, then for over
a quarter of its length, it drops 81 feet on a
uniform slope. The pressure of the water it carries
builds as the tunnel turns down to a 50 percent
slope, plunging 154.2 feet in a short 222-foot
section. It then levels out for 50 feet before
entering the turbines.
The flat section of the tunnel has concrete walls
and the balance is lined with steel.
At the eastern end of the dam near its upstream
face, 300 feet below the maximum surface level
of the reservoir, a 21-by-12-foot steel gate operating
on a dozen 33-inch diameter wheels provides for
emergency closure. The 81-ton gate was fabricated
by Voest of Austria. It was so large that it caused
major problems getting through German railroad
tunnels to reach the seaport from which it was
to be shipped to Stockton and then carried by
rail and truck to the New Don Pedro Dam site.
The gate was installed on July 23, 1970.
The same month the three 61-ton transformers
built in Italy were received at the Port of Stockton,
the heaviest electrical equipment ever imported
by this country.
At the other end of the tunnel, there were problems.
The huge manifolds which divided the water into
a six-foot diameter flood-control outlet and three
8-foot diameter tubes to feed the turbines were
99 days late on delivery. Furthermore, the flood-control
outlet as improperly designed so it had to be
rebuilt on the sight.
The manifold, consisting of three "Ys" serving
the turbines, the flood-control outlet and connections,
weighed 400 tons. The units were shipped to Oakdale,
where they were stress-relieved in gas-fired ovens.
Most of the welds had to be redone.
Each section then was trucked 30 miles to the
site for final assembly. The largest section of
the manifold, weighing nearly 200 tons, proved
Not far out of Oakdale, the driver of the special
rig hauling the steel monster approached a power
line which he feared was too low to clear. When
he applied the brakes, the load shifted and crumpled
After a considerable struggle, the massive "Y"
was loaded onto another trailer. About two-thirds
of a mile down the road, the truck hit a soft
spot in the paving. The trailer wheels sank up
to the bed. Another struggle.
Finally, the load reached the project haul road
which was built to support heavy weights, but
the difference in grade between the access road
and the haul road was such that the long trailer
hung up in the middle. Had it not been so heavy,
it would have worked like a teeter-totter. After
much head scratching and conversation by the crews,
the two biggest pieces of equipment were hooked
to the truck tractor and the whole load was dragged
off the ridge. For a moment it was feared that
the huge earth moving tractors would pull the
truck apart before moving the stranded trailer.
The tunnel and all its equipment were operational
by August 1970.
Meanwhile, the construction of the powerhouse
proceeded, with the excavation starting July 15,
1968. The first concrete for the foundation was
poured on April 14, 1969. The powerhouse, 99 feet
wide and 171 feet long, nearly fills the Tuolumne
River canyon; only the switchyard separates it
from the downstream toe of the dam.
Because of the weight of the turbines and generators,
a tremendous amount of reinforcement steel was
enclosed in the structure.
Goodier recalled that on summer days the builders
had problems with independent-minded iron workers
hired to place the reinforcing steel into the
concrete foundations. One morning, the superintendent
fired two "re-bar" workers for drinking beer on
the job. Going upstream to play in the river,
they found a raft and opted for a joy ride. Suddenly,
they found themselves in fast water at the mouth
of the 30-foot diameter diversion tunnel, which
was running about half full.
"Talk about white water. That was real white
water," Goodier said. "The raft hit a center pier
at the mouth of the tunnel and the partially intoxicated
rod-busters were knocked off, but when the raft
got around the pier they were able to grab hold
of it and hang on for dear life."
There was little doubt they would have drowned
had they not caught the raft; a body will sink
quickly in the foam of white water because it
is so full of air. They survived the fast two-thirds
of a mile swim through the tunnel, but Goodier
surmised that was the wildest ride the pair ever
had. They were last seen headed for home on a
dead run, probably quite sober.
Non-movable parts of the turbines were installed
during the first-stage pouring of concrete, which
was completed in September 1970. Turbines were
embedded further during the second-stage concrete
pouring, at which time the generator floor also
Next, the generators were put in place, followed
by more than two weeks of operational testing.
With the water rising rapidly behind the new dam,
the first generator was pressed into power production
on December 11, 1970, well ahead of schedule.
This was done mainly to lower the water level
of the reservoir because of the anxiety that the
growing lake would flood the still-unfinished
Jacksonville bridge and other roads whose relocation
had not been completed.
The second generator was placed on the line of
February 2, 1971, and the third on March 10, 1971.
The powerhouse was in full operation, serving
Modesto’s share of the energy would meet about
a quarter of its needs. Turlock was more fortunate
in that it had about 75 per cent of its power
requirements met by New Don Pedro. In the years
to come, the Modesto Irrigation District was to
be faced with the need to search far and wide
for more energy to serve a growing population.
Formal dedication ceremonies were held May 22,
1971, when some 3,000 people heard San Francisco
Mayor Joseph Alioto declare:
We have harnessed a great river
to serve man. There is a vision, imagination,
a sense of beauty about it. Environment and development
will never meet, but a delicate balance of the
two has been achieved at Don Pedro Dam.
MID Board President Mathew Fiscalini, the master
of ceremonies, noted that twice within a half
century people had gathered on the spot to dedicate
a great dam, first in 1923 and then in 1971.
When all the bills were paid, the New Don Pedro
Dam and Powerhouse project had cost $115,697,000.
Millions of dollars in bond funds not yet needed
for progress payments to contractors were invested
in various ways. In one instance, several thousand
dollars in interest was earned in a single day
because district officials hurried down a Sacramento
street from the Department of Beaches and Parks
with a multi-million dollar check in order to
deposit it before the banks closed.
The $8,293,000 earned by investing the bond money
reduced the total amount each agency paid toward
the project’s total cost. In the end, San Francisco
paid out $47,380,000, the TID $32,071,000 and
the MID $14,865,000, for a total of $94,316,000.
The $8,293,000 earned interest plus the Davis-Grunsky
$7,623,000 and the Army Engineers $5,464,000 paid
the balance of the total $115,696,000 cost of
The construction of New Don Pedro rivals the
monumental undertakings of the Modesto Irrigation
District’s creation a century ago, the building
of old Don Pedro 65 years ago and the decision
a half century ago to enter the retail power business.
Each required courage, vision and determination.
In many ways, however, the completion of New
Don Pedro marked the end of an era and the start
of a new period filled with the challenges of
obtaining new power sources, domestic water supplies
and recreation management in a computerized environment
undreamed of in 1887.
Continued courage, vision and determination have
been demanded of those who are and will continue
to meet these challenges successfully.