I had come to understand and discuss some of the hazards of the mouth of the Columbia River which beset shipping bound to and from the Port of Portland. The fabulous evergreen forests of the Columbia River drainage, run through regional sawmills, provided lumber for buildings for the West Coast's 19th century population expansion.

The abundant wheat crops compelled the attention of, in particular, ships from Great Britain which were charged with importing food to feed the laborers of their Industrial Revolution.

The economic pressures resulting from these assets were forcing 'the powers that be' to deal with shipping difficulties: the accursedness of the North Pacific weather, particularly in winter; primitive navigational instruments making it hard, if not impossible, for a captain to know exactly where he was — one degree's difference in his sextant's reading equaled a physical difference of 60 miles — the lack of light houses near the Columbia River entrance; the ever-changing sands of the entrance which could suddenly shallow — or fill — a formerly reliable shipping channel; the vagary of the wind's dying when a sailing ship was in mid-Bar; the ever-increasing size and depth of ships; the possibility of losing a crew to shanghaiiers; the difficulties of getting a full cargo back out over the Bar.

Forces were at work dealing with things: at the start, Astoria's most important asset was the apparently fearless Captain Flavel. He understood the waters at the mouth of the river as no one else. Shippers and business interests in the region grumbled about his rates but if he couldn't deliver your vessel safely, likely no one could. As other bar pilots began to learn from him, and as they bought steam-powered pilots boats — so that the pilot boat wasn't dependent on the winds — piloting improved.

The federal government was building regional lighthouses — Cape Disappointment, Point Adams, Tillamook Rock — and was accepting the fact that even more would be required, including a lightship offshore, a lighthouse on Desdemona Sands inside the mouth of the river, and another lighthouse at North Head.

The Corps of Engineers knew that if they could narrow the river's mouth it would increase the speed of the ebbing tide and scour out the sand which had piled up on the bar. That would increase and regulate the depth of the water. This meant building rock jetties out into the river and the ocean.

They started first with a rubble stone jetty on the Clatsop Spit — the South Jetty — then extended that jetty, then planned one for the north shore of the Bar — North Jetty — and, eventually, a third — Jetty A — plus pile dikes built out from Sand Island and Jetty A. Together, all these projects did the job, but it took 50 years for the first round to be completed. And since deterioration is the way of the world, these projects have required continuing maintenance.

The Corps dredged the bar to help clear accumulated sand, repaired the jetties' damage done by winter's storms, and, almost always, expected the cost to be more than estimated as the job proved ever more complicated.

The science of jetties

Once the South Jetty was well-started, Scientific American magazine wrote about it in January 1898. Their commentary included theory: "The theory of the training jetty is based upon the fact that the velocity of a given volume of water in passing through a channel in a certain time will be proportional to the area of the cross section of the channel. The smaller this cross section, the higher the velocity." Therefore, they needed to narrow the mouth of the River. These days, this is described as "the fire hose theory."

The Scientific American article restated the problem for a national audience: "The crossing of the bar, which required great caution at any time, became positively hazardous in boisterous weather, and the grain ships which arrived off the bar when a heavy sea was running, or the weather was thick, were liable to be detained on a dangerous lee coast for several days."

[In addition, the bar is unusually long (six miles), wide (three miles), and it bends in the middle. The height difference between the river and the ocean is about 10 feet; as someone at the Columbia River Maritime Museum explained to me, "That's like a 10-foot waterfall out there."]

The magazine article concluded by defining the economic value of the work: "The construction of this important work has served to call public attention to the rapidly growing commerce of the Northwest, and the part which the Columbia River with its tributaries is destined to play in developing the states of Oregon, Washington, Montana, and Idaho. This wonderful river drains a territory fully four times as large as all the New England states combined."

Battle of the worms

As the South Jetty was thought to be completed in 1895, the river's channel deepened but several years later it began to shoal again. By 1902 it was clear that more work was needed to stabilize the bar. Soon it was also seen that the repair which had been done in the summer was undone by the that year's winter storms.

Part of the failure was of the pilings on which the railroad trestle was built and upon which the boulders were hauled out for dumping onto the jetty. They were quickly riddled by ship worms - teredos. One year's worth of the teredos' toothsome activity skeletonized many a piling. ("During the fall and winter of 1904-5, 12,000 linear feet of trestle were destroyed, due to the weakening cause by their action," reported the Corps of Engineers to Congress in 1906.)

There was also difficulty in getting enough money quickly enough from Congress to complete the work before nature disassembled that work. ("I can not measure this loss in dollars and cents. It will amount not simply to a delay in the work, but may result in an enforced duplication of a large part of the portion now built …" wrote Brig. Gen. A Mackenzie, Chief of Engineers.)

The two-and-a-half-mile extension of the South Jetty was completed in 1913.

One jetty not enough

Even at that, however, the Army Engineers realized that a jetty on the other side of the River's mouth was necessary, so they began construction of the North Jetty in 1913. That job went fairly quickly, being completed in 1917. The location was more protected from the blast of south storms and the crews could work all year. With the completion of the North Jetty, the depth of the bar dropped to 40 feet.

As the Pacific's westerly waves continued to break themselves against the massive stone walls of the jetties, they tended to "unravel" them from the westernmost end. Winter's storms produce continuous waves of between ten and almost 30 feet in height. That beating tends to pick apart the stonework. The jetties, as massive as they are, are humbled by this continuing assault which moves even the heaviest stones and undermines the foundation on which they are piled.

That unraveling made the jetties less effective, at the same time the ships of the maritime fleet continued to grow ever larger, requiring the complete project at full length to keep the bar's 40-foot depth.

To stop this disintegration, the Corps first tried gluing together all the rocks at the end of the South Jetty with 13,000 tons of hot asphaltic mastic. That failed and the jetty continued to come apart at the rate of about 300 feet in length per winter.

Next, they contrived a huge solid concrete terminal built on the outer stones above low water level. That slowed the decimation of the rockwork and allowed the scouring action of the confined ebbing tide to maintain a more dependable bar depth.

Fierce onslaught

With the completion of the two-mile-long North Jetty in 1917, the Corps realized that the mouth of the Columbia River was an ongoing project requiring continuing maintenance of the rock constructions, dredging of the mouth of the river, and building one more jetty. (That third jetty, 'Jetty A,' is around the corner from Cape Disappointment Coast Guard Station.) That final jetty and the accompanying nearby pile dikes would guide the outflowing tide toward the middle of the bar and thereby reduce the pressure of the water on the North Jetty. That was completed in the late 1930s.

The Columbia River Maritime Museum in Astoria quotes Corps of Engineers District Engineer S.W. Roessler as asserting about the mouth of the Columbia River, "…[N]o language can adequately describe the fierceness of the onslaught. The place must be seen to be understood and appreciated. It is perhaps no exaggeration to say that there is no work in progress in the U.S. today at all comparable with this one in the difficulties, uncertainties, and dangers that arise at every stage of its construction." This from a man who had worked the width and breadth of the United States.

Expensive vital assets

Since 1984, the mouth of the river has been maintained at a channel depth of 55 feet.

In 2006, the Daily Astorian quoted Dave Hunt of the Columbia River Coalition as saying, "We've been having 'five-year storms' almost every year." The storms were opening holes in the jetties, shoving the rocks around, and had significantly shortened all three jetties.

Since 2015 the jetty contractors are using higher quality, more dense rock and placing it more carefully. They are placing flat surfaces in contact with flat surfaces, as if they were working a giant three-dimension Tetris puzzle. Corps civil engineer Jerry Otto was quoted as saying, "The key is to have as much interlock between the stones as possible."

He also added, in 2016, that the work taking place then on all three jetties was planned to last through 2023, that this infrastructure allows a vigorous trade economy of perhaps $24 billion which is said to employ perhaps 40,000 regional citizens.

The jetties are an asset to the world, wherever wheat and timber are traded: a very expensive asset, but an essential one.

31 tons

Today, in the summer of 2019, as the Corps repairs the North Jetty, we watch a procession of big strong long trailer-tractor rigs haul one or more enormous boulders between Warrenton and Cape Disappointment.

The other day, as a friend and I stood in her garden in Chinook, we watched one truck drive by with a single rock that was spray-painted "31.3." "That," she commented, "means that stone weighs 31.3 tons." 31 tons! That approximates the weight of five adult elephants …

As of summer 2018, the eventual total tonnage of rocks being added to North Jetty during the current project was forecast to reach 140,000 — or 280 million pounds.

The really numbing thought for me here is that the waves of the Pacific Ocean can shove that boulder and its brothers around almost as if they were logs. That just will not compute …

A personal note from the writer:

Since we last spoke I‘ve had an impressive case of the flu, followed by aFib and congestive heart failure, from which I’m recovering. As a result, I’ve forgotten where I was. Perhaps you have, too.

Recommended for you

(0) comments

Welcome to the discussion.

Keep it Clean. Please avoid obscene, vulgar, lewd, racist or sexually-oriented language.
PLEASE TURN OFF YOUR CAPS LOCK.
Don't Threaten. Threats of harming another person will not be tolerated.
Be Truthful. Don't knowingly lie about anyone or anything.
Be Nice. No racism, sexism or any sort of -ism that is degrading to another person.
Be Proactive. Use the 'Report' link on each comment to let us know of abusive posts.
Share with Us. We'd love to hear eyewitness accounts, the history behind an article.