On Mach 28, 1947, Guy F. Atkinson Company was awarded the first Contract to construct McNary Dam, on a low bid of $743,485.00 for work involving rock and common excavation for the lock and lock approach, construction of access road and railroad siding, and a small overpass.

On June 1, 1947, Al Chaussee and Jack Sinfield arrived at the Washington shore to organize the initial operations and found 16 feet of water covering the site. They waited six weeks for the Columbia to recede enough to permit them to start excavation, during which time they busied themselves planning the necessary buildings, directing the building of roads and a bridge over the railroad track.

One year later occurred the second most disastrous flood in the history of the Columbia, completely wiping out Vanport City, the second largest city in the State of Oregon. To eliminate such property damage and loss of life, as well as to provide hydroelectric power and navigation in the Columbia River Basin, the huge McNary Dam is being constructed.

An idea of its gigantic proportions may be gleaned from the following statistics: Approximately 18,480,000 cubic yards of rock and earth will be moved in excavating the site and in rolled embankment. 1,710,000 cubic yards of concrete will be required.

Approximately 88 miles of railroad will be relocated necessitating 1,100,000 cubic yards of rock excavation and 5,000,000 cubic yards of unclassified material for embankments. Approximately 25 miles of highways will be relocated requiring 6,000,000 cubic yards of rock excavation and 1,400,000 cubic yards of unclassified material for embankments.

People residing in the areas adjacent to the huge 58 mile reservoir behind McNary Dam will be protected by levees requiring 3,250,000 cubic yards of material for embankments.

The second contract was also awarded Guy F. Atkinson Company, on a bid of $1,120,651.00 for the construction of the first step cofferdam, behind which were constructed the navigation lock and 13 of the total 22 bays of the spillway.

Subsequent awards made to Atkinson, Ostrander and Jones Companies, joined in a venture under the name McNary Dam Contractors, were: 3rd award on a low bid of $21,648,763.00 for the construction of the navigation lock and 13 vays of the spillway and 4th award on a low bid of $15,835,539.50, for excavation for two powerhouse units and their construction. Construction of an assembly bay for the powerhouse, and construction of the second step cofferdam and its attendant diversion of the Columbia River. In addition, 3,280 13-ton concrete tetrahedrons were made for the river closure.

Some of the problems involved during construction include:

1. Provisions for spring and fall migrations of fish to the spawning grounds.

2. Daily transportation of men and equipment across the Columbia River on barges.

3. Final closure of second step cofferdam including the most difficult river diversion every attempted.

4. Annual spring floods.

When a 30 day delay in delivery of steel piling for cofferdam construction was announced in January 1948, it seemed a fatal blow to hopes for completion of the first step cofferdam that spring; an almost certain delay of six months in the construction time table, and a loss of much of the earthfill cofferdam work already completed.

But the projected rate against the rising waters of the mighty Columbia resulted in so much of a triumph for the contractor that it never looked like a real race. Guy F. Atkinson Company, winning hands down, had the first step cofferdam in place by early April, well ahead of high water. Nineteen cells of 15″ interlocking steel piling were threaded, driven and filled in little more than six weeks.

The original plan was to build one timber template for each size cell, string the piling around the template, drive it, and then move the template to the next set-up. When it became apparent that delivery of the steel piling would be delayed almost until March, with only six weeks time then left for building the nineteen cells, the outlook for this driving schedule looked very bleak indeed.

The problem was whipped by building nineteen templates, one for each cell built into place and ready for stringing as soon as the piling was delivered.

At that time it was found that the City of Los Angeles was receiving its steel ahead of schedule and arrangements were made, for a fee, to divert 500 tons to our use. Also the excess timber was costly but it saved the job.

In the spring of 1950, it was touch and go when the rising waters of the Columbia were lapping at the top of the junior cofferdam. Crews were hastily called, equipment worth in excess of $100,000.00 was quickly removed from the “Holes” and, working day and night the cofferdam was raised to a safe height. Again the constractor won a battle with the mighty river, and again at a cost of many thousands of dollars.

During the summer, with the exception of fighting high water and a few thousand other major and minor difficultues, progress was fairly smooth. Then came final closure of the second step cofferdam and diversion of the river.

The last cells of the upstream leg were being driven and strung into place while the first of the tetrahedrons and “B” rock (weighing approximately 2 tons each) was then resumed until they reached a level higher than the surface water which had now risen more than 18 feet as it struck this barrier and diverted to the spillway on the Washington shore.

Among many distinguished persons who visited McNary Dam November 16th to observe the final closure were Guy F. Atkinson, E.B. Skeels and President George H. Atkinson and his three sons. Army personnel were led by Major General Lewis A. Pick, Colonel O.E. Walsh and Colonel W.H. Mills.

At this writing the contractor is again fighting the mighty river, whose waters have risen during that last few days to a point dangerously close to the top of the cofferdam. But the silver lining in theis dark cloud is the remarkably fine weather we are enjoying at this time of year.