Nelson Bridge

Nelson Bridge

The bridge at Nelson is important to Nelson and the West Kootenays. Before it was built in the

late 1950s, there was a ferry right beside the place where the bridge was built. It was part of the

southern Trans-Provincial Highway at that time. So, you would come in from the Okanagan

through Grand Forks and then come through Castlegar to Nelson and continue east to Alberta.

Before the bridge, you would have to use the ferry at Nelson, which got overloaded.

The bridge was needed to access what is called in Nelson the north shore (the most prestigious

place to live in Nelson), where there are many million-dollar properties. For a stretch of twenty

miles, it’s nothing but houses. Every couple of hundred feet, almost like city lots along the

lakeshore, there is a cottage or a substantial house, until you get to the village of Kaslo.

So, the bridge is really an important connection for the national and local highway system. It is

used a lot today, with traffic almost bumper to bumper in the morning rush hour. We had a traffic

study done for building the mall, and there were ten thousand cars a day coming into Nelson and

leaving at night.

One of my most memorable jobs was the year and a half that I spent on the Nelson Bridge

shortly after moving to the area. I was hired to be the surveyor, in large part because I was an

engineer, too. I did the layout and was the technician, checking concrete and so on. The bridge

work had already started when I was hired. But they had not put in what they call bents, smaller

piers, while the bridge is elevated. The main piers were out in the water where the channel was

eighty feet deep. Placing the piers in the right place was a challenge. I spent six months working

on them.

I think there were to be five smaller piers. They would be on dry land, so it was just a matter of

measuring an already predetermined site where the bridge would go and the length of the bridge

and everything. It was my job to make sure that everything was put in the right position, and to

determine where the steel would later be placed. Lo and behold, my work was good. It's kind of,

I hate to say it, and don't put it in print, but it is bragging rights. They believed in me, and I was

very confident.

Anyway, I trusted my surveying. Today I have to use the word “trust” almost foolishly. I was

working for the consultant who was responsible for making sure the bridge was built adequately,

properly, according to his design. The contractor was Peter Kiewit, and the superintendent was

Bill Hit; he had two engineers on his crew.

Kiewit should have laid out these piers, and I, working for the consultant, should have checked

them. But something went wrong with this normal procedure. I did all the layout work, and

nobody else checked it. I had to check my own work.

Later in my career, I was a consultant and responsible for other bridges, so looking back on the

Nelson Bridge experience, I can't believe that a structure that serious, big, and expensive was

built without someone else checking those piers. You need to have zero tolerance for mistakes

and always factor in safety. You've got a little bit of leeway, but on a bridge, you must be right

and precise, at least within millimetres.

Although I was busy laying out the bridge, doing inspections, and checking concrete, admittedly,

there was a senior person to me making sure everybody was doing their job. He made sure I did

everything that was required. I can remember checking concrete, and if it was delayed too long,

we'd reject it, and they'd have to take it away. They probably took ten truckloads of concrete

away and threw it out.

We ran into some real challenges on the Nelson Bridge. The first challenge was installing big

concrete pilings twelve feet in diameter to what they called the grillage down at the bottom in the

right place. The pilings were very heavy, perhaps thirty or forty tonnes. To support them, air

tanks had to be used. To lower the concrete, they let the air out of the tanks or let the water

compress the volume, so the floatation would diminish as it went down. But this system failed.

Then they used two cranes—big cranes, one on each barge, on each side of this structure. They

would also control letting the concrete go down. There were probably a half a dozen compressors

supplying air. The volume of air would diminish as it went down into the water, and the cranes

were supposed to make up the loss of buoyancy of the air tanks. The whole thing failed because

the compressors could not keep up with the air. But we eventually got that done.

Another problem was with a pier that required what they called cofferdams, watertight

enclosures. Sheet piling had to be hammered in around the position where the pier would be

placed. The piling created an enclosure and extended from the mud on the bottom of the lake by

twenty feet to the top of where the pier would be. Then water had to be removed from inside the

enclosure. When that was done, the pier could be placed in there and concrete poured into the

forms.

Then we had to move out into eighty feet of water. Two piers had to be installed on the lake

bottom. That was quite a chore; even today that would be quite a chore. The consultant who

designed the bridge was working for the Highways Department. His job was to make sure the

bridge got built according to the design. But he was not sure how to place piers in the water

eighty feet below the lakebed, within an inch or so of the prescribed position. To do that, they

had what they called the base form. They used twelve-inch-diameter steel pipes hammered into

the clay at the bottom of the lake. They hammered eighty feet into the clay until they could not

hammer anymore.

The crew used to get very annoyed because quite often when they were hammering, they would

run out of pipe. So, they would have to weld another twenty-foot-long piece onto the existing

piece.

I do not remember that they ever got the enormous pipes to move again after they welded the

new piece on, but you had to be strict with yourself and try to make them move. You could not

assume that the pipe would not move. And here I was as an inspector, out there in the cold,

miserable, in the middle of winter, hammering on those pilings, and then saying “No, you’ve got

to weld it on and then you've got to hammer it. See, if you can, if it'll move anymore.”

Eventually, the pipe would not move anymore. And then we'd have to say it was okay.

It was up to Harold Kerslake and I—me as surveyor and him representing the company

responsible for building the bridge—to solve the problem with the base forms. We put together a

whole new system of positioning those base forms in the right place by hammering and piling. I

had to measure where that piling was, and then we adjusted the base form to fit, moved it into the

right place, and fastened it down and anchored it.

The whole project was copyrighted by Peter Kiewit, the contractor that built the bridge, and his

company, because they effectively invented this newer and better way of doing things. I could

not let anybody know. I went six or seven years before I ever let anybody read about the process.

Then, the second pier went in with that system that we developed. It went in lickety-split, just no

problems whatsoever, except that it needed a bunch of fill on the north shore. Because I was

familiar with the area, the properties, and everything else, I personally scrounged gravel off three

or four different properties in the adjacent area. I put the fill into what they call the approach to

the bridge on the north shore. On one occasion, it failed and slid out into the lake. We were

worried that the fill was unstable, but we carried on.

On one of the piers, a big decision was made, which I did not get really involved with. The

workmen kept excavating to make the original design work. Both gears were the same length,

but the pier positions in the channel were not the same depth. The workers kept trying to dig out

the channel on the north side, so the pier there would be the same height and length of the other

pier. As they dug and dumped the material downstream in the river, they saw that something

funny was happening. The removed material was filling in the base of the second pier. They

decided to make that pier shorter, which was acceptable.

To pour concrete into eighty feet of water, they designed a system that was being used at the

Kitimat power plant (an aluminium plant in Northern BC). The university lab had tested the

concrete that was being poured at Kitimat. I had watched the concrete being poured while I was

at university because I was class president of my civil engineering group. I was interested to see

how they did it. To make concrete in eighty feet of water, you cannot pour it in because it will

just disintegrate. So, after the Nelson Bridge’s steel forms (piers) were fixed in place, the plan

was to pour a cement mix inside, a very fine mix called a slurry. A Montreal outlet claimed that

they knew how to make it.

So, a group came in from Montreal. I got to be very friendly with the superintendent. After they

had fixed the steel form to the rock below, the group was ready to pump in the slurry. It would

go to the bottom of the pier and would gradually rise, pushing the water out. The water would

spill out the top because the concrete mix would be heavier than water. The cement was

considered adequate for holding the pier in place on the rock.

The test from the Kitimat power plant showed that the process could make good concrete if it

was done properly. But the company could not get their slurry to pump; it would jam in the

pipes, which are only maybe two inches in diameter.

And boy, they tried to make the process work. They brought in sand from Spokane, Washington.

I always remember it coming in boxcars. By the time it got to Nelson, the sand was frozen solid

in the box and had to be jackhammered out. So then, I personally located a sandpit south of

Nelson where my folks had gotten sand for preserving vegetables through the winter.

The Montreal group tried to mix the sand into the cement, but it just would not work. So, the

company had to be let go. They just had to give up on the project. And of course, it was a major

job in those days. They had spent a lot of money trying to make it work. Another outlet out of

Chicago came in with a similar process, but they had an additive to combine with the cement to

make it very viscous.

This process worked and is still being used today in cement that has to be pumped. The additive

was added to the sand mix, and the mixture was pumped in to fill up the steel forms. Above the

steel forms was a section that had to be made of concrete. This exposed concrete had to be

placed in wooden forms—plywood forms. They would pour eight feet of concrete at a time.

A set of anchor bolts had to be fixed to the steelwork. The measurements had to be precise,

within a quarter of an inch or so. I was doing all the layout work and the measurements. But

when they were ready to pour in the mixture, I said that I had to check my work. Here they were

pouring the cement and relying on my work. I was just checking that it was done right, but I was

the only guy checking. It was a very funny position to be in. I was not responsible to the

contractor, but I told the crew that I was not going give them the position for the anchor bolts

until I had checked my work.

The contractor got upset and decided that they had to go ahead and pour the concrete. They

drilled these holes four inches in diameter where the anchor bolts would later go in. Well, as it

turned out, it was difficult to drill those holes into the reinforcing steel. Getting the process right

cost in the neighbourhood of four thousand dollars just because the guy decided they had to pour

the concrete at that moment. He could not wait a week.

It took a few days for me to make all kinds of measurements. I was triangulating. We did not

have the equipment that we have today. Today, that job would be one-tenth as difficult as it was

back then.

I had stood up to the contractor. I never found any mistake or inaccuracy in my work when I did

it all over again to double check it, and it turned out that it was correct. But I was not going to

give the contractor the OK to proceed after the initial measurement was made.

A decision was made to strip the forms of the recently poured concrete. On one occasion

working on the fourth pier, they stripped the forms off, and the concrete just fell into the river.

The concrete was still green, and it was not cured enough to be stable. The job had to be done

over again.

A few problems surfaced when we were trying to elevate the deck (what would become the road)

to make the connection to the first pier. The workmen were adding steel to the pier, and they had

what they call the falsework holding it up. And we tried jacking the deck up because we knew

the level was not going to match the level of the first pier, and it didn’t. When part of the deck

got out to the pier, instead of connecting at the right elevation, it was four or five feet too low.

We had had a landslide, and the shoreline side was uneven and was moving a little. The

shoreline started to slip, but the falsework (temporary work) was not failing. The ground

underneath was failing and collapsing. They decided to quit trying to build up that side of the

slope. We had to lift the deck instead of dropping it down; normally, the deck would be dropped

down to match the level of the pier. But this was the reverse. We had to lift it up to match the

pier. But everything fit very well after that.

One last thing about the Nelson Bridge. I was the first person, other than the iron workers, to

walk across the bridge on a beam eight inches wide. I was wearing office clothes and leather

shoes. Now it was not all that narrow, but I was scared, petrified actually. I had not realized how

critical the rubber-soled shoes we wore during construction were for balance.

It was like being on ice. It was slippery, and I was eighty feet above the water. I should not have

been there. I was not employed to do this, and if I fell in and hurt myself, I do not know if I

would have received any compensation. It is always scary to be part way through something and

realize that you should not be there. I was sticking my neck out needlessly just for the privilege

of saying I was the first person to walk across the bridge in Nelson, other than the iron workers.

Working on the Nelson Bridge was a tremendous experience. I was only twenty-seven years old

or so, and I wrote my thesis on the bridge project, and I made up a nice, big loose-leaf binder

about it. After the bridge work, I was laid off by AB Sanderson Company. They wanted me to

look after the Alexandra bridge along the Trans-Canada Highway north of Hope, but I turned

down the job. I did not want to leave Nelson to work on another bridge. I had had enough. I

wanted to work in Nelson on smaller, more meaningful, personal-type contracts. The people at

the consulting firm could not believe that I would not carry on being a construction engineer, but

I would not go for it.

The consultant fellow even came out from Victoria up to Nelson, which is a day’s drive, to try

and talk me into it. I just had to say, “No! I am not leaving Nelson.” At the time, there was talk

of putting a university in Nelson. We planned to have a lot of kids, so a university was important.

It turned out we never did get a proper university here.