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Cabling on The Brooklyn Bridge, NYC

A VERY good book on the Brooklyn Bridge is David McCullough's "The Great Bridge".
So many facts & figures and detailed info about John Roebling and his son Washington whose passion was building the bridge.
 
Marty,

Thanks for posting those pictures.

Note that the workers have soft hats. It's amazing that anyone can keep a hat like that on their head while working aloft, what with the winds up there.

JRR
 
My testicles just want to crawl up inside me when I see stuff like that. My hats off to those who can stand heights, doubly so for the pre-OSHA era. Did these guys get "hazard" pay?
 
No hazard pay in those days, it was part of the job. Chances are those guys may well have been former sailors who sailed "before the mast", so climbing rigging in the wind with no safety gear was (pardon the pun) "old hat". The old adage was "one hand for the ship, one hand for yourself".

I thought the same thing about how those guys kept their hats on in the wind up there. Maybe they wore tighter fitting hats.

The times those guys worked in were harder times. If you did not like the working conditions, you found something else to do in some other line of work- assuming you could afford to quit your job and move on. During the Great Depression, the story was told that on any highrise job in NYC where steel was being set, there were always a few unemployed men hanging around outside the jobsite fence. Whenver someone fell from the high steel, there were men ready to take his place, never mind the conditions.

During WWII, my cousin welded in Federal Shipbuilding in Kearney, NJ. My cousin used to give me odd bits of advice. One thing he used to tell me was never to coil my welding lead over my shoulder to take the weight of it off my hand holding the stinger (electrode holder). My cousin told me to make sure to tie my lead off to something, even if I had to temporarily weld a hook to some part of the job I was working on. My cousin told me the story of how he had this lesson hammered home. One night shift, he and another boilermaker welder were assigned to go up on the mast of some ship to weld some sort of joint or connection that had been set and fitted on day shift. They went up in bosn's chairs. My cousin told his partner to weld a hook to the side of the mast and tie his lead to it. The partner said he'd do fine with the lead looped around his shoulder. During the shift, someone came along the deck of the ship, looking for "spare" welding lead, to save having to drag more welding lead up onto the ship. Whomever this person was, they grabbed and tugged any lead they spotted, figuring the dayshift may well have left the lead coiled loose on some staging.

My cousin said when he raised his shield to put another sitck of electrode in his stinger, he did not see his partner's arc reflected off the mast, nor did ne hear the partner chipping off his weld. He looked oaver and saw the empty bosn's chair. About then, all hell broke loose as my cousin's partner had been pulled backwards out of his bosn's chair and fell to his death on the deck. As my cousin told it, he ate two lunches that night, and his late partner, being recently married, had packed a better lunch. My cousin was full of interesting tips he had learned the hard way.

You have to consider the times. My cousin had come thru the Great Depression. He had made extra money to feed his wife by racing stock cars on a dirt oval, and boxing what were called "smokers". If a man would get in the ring with strangers who were just as desperate to bring home a few bucks so the family could eat, climbing a mast to weld was not so fearsome. Most of the old guys who worked at jobs like those painters were pretty rough. They may well have learned their climbing and rigging skills on sailing ships, and may well have boxed to pick up a few bucks when out of work. They were a different breed. Whisky with a free lunch in the nearest saloon (free lunch being pickled eggs, hardtack crackers, herring and Limburger cheese, maybe a pickled pig's foot...), and they probably chewed cut plug tobacco while up painting (claiming the whisky and tobacco cut the paint fumes and kept their throats wet and opened).

I got out of engineering school in 1972 and went to work for Bechtel on powerplant construction. In 1972, there was no fall protection required. Ironworkers wore belts with lanyards. More often than not, these belts were used to hang spud wrenches and bolt bags off of, not so much for fall protection. I was a young engineer, and I soon got up on the steel with the ironworkers and boilermakers. I got to where I was walking the iron. I remember on this one job, I was the engineer in charge of a contract to install some new boiler flue gas breeching. It was large fabricated plate steel ducting, run on support "bents". The biggest section of the ducting was at least 10' wide x 20 ft high. It sloped up to connect with a flue in a 400 ft tall concrete stack. The tie in point to the flue in the stack was about 100 ft off the ground. As the job went along, there was a question about the centerline of the breeching. The contractor and I were going to have to work it out and establish the centerline. I took a transit on its tripod, and put it over my shoulder. The boilermakers took the canvas bucket with the steel tape, plumb and a few other tools. I remember we took an elevator to the top of the boilerhouse in the existing portion of the powerplant. We walked upstairs to the roof, and we set up the transit over a centerline marked on the roof, took a backsight, then turned the instrument 180 degrees. One of the boilermakers walked out on the open iron and I put him on line. He made a couple of punch marks. Then, it was my turn. I had to step off the parapet of the roof and down onto a 10" wideflange beam, carrying the transit on my shoulder. No "cooning" (sitting on the beam and sliding along) when you are carrying a transit. No belt, no harness, no nets. I got to this connection point, where several horizontal members met. We set up the transit (no optical plummet, old style plumb bob on string). One of the boilermakers cooned the iron and made some heavy punch marks for the points on the legs of the transit so they would not slide off the steel. I took a backsight and carried my line onward. I remember trying to sight through the transit, focus the image and sharpen the reticle, all the while keeping my feet planted solidly on the steel. We did what we had to do. The contractor had a young civil engineer, fresh out of school. He walked the open iron like he'd be going down his own street, and used to stand there with a surveyor's field book, writing notes or readings like he was standing on the ground. That civil engineer and I both got our Professional Engineer's Licenses at the same time, putting some of our time in on that job, and sitting the exam in April of 1977.

After awhile, I got kind of cocky about going on the steel. The boiler drum elevation was 193 ft above ground level. That was a lot of stairs. The steel erecting contractor had a couple of Manitowac "Vicon" cranes on site. The boilermakers introduced me to the habit of "riding the ball". If several of us needed to go up or down, we might hook a "scale box" (aka, a "skip") to the whip line of the crane. If it was just one or two of us, we rode the hook on the whipline. Lunchtimes were another story. We had one half hour start to finish, for lunch. As soon as the "washup whistle" sounded, if we were up at the drum elevation, we either jumped into the skip or hopped onto the hook, depending what was available. Down we'd go, with the operating engineer in the crane using the "Vicon" control to give us fast acceleration and a smooth stop. One of us would hang wide off the hook with an arm extended to signal the crane operator or his groundman. Often, one of the foremen would have a stake rack truck sitting ready, engine idling. We'd jump off the hook or out of the scale box and onto the bed of the stake rack or a pickup. Off we would race to the local tavern.

This is another bygone thing, the heavy semi-hydraulic lunches in the taverns. At the door of the tavern was a line of men off the jobsite, many in their connecting belts with spud wrenches jangling. No table or chair in that old tavern had four matching legs. The toilets were lagged to the floor with 2" flat bar, and the toilet stall partitions were 1/4" diamond plate welded to 2" black steel pipe. A galvanized steel piss trough with a perforated pipe completed the fittings in the men's room. Walking into the tavern, you'd come to a table with shots of rye whisky (probably Overholt or Kessler's in those days) lines up. If you were so inclined, you grabbed a shot and downed it. Next table, there were opened quarts of beer. You grabbed a quart of beer, took a good pull to chase the whisky. As you held onto your quart of beer, you moved to the next table. Two older men, gimped up from either iron mining, railroading, or logging, were cooking bratwursts and kielbasa on electric griddles. You hollered out whether you wanted a brat or a kilebasa. They handed it to you on a roll, and you slopped on good straight horseradish, and a slug of chopped raw onions. You took the first seat you spotted, sat with whomever was there, and ate your sandwich as quick as you could while polishing off the remains of your quart of beer.

You got up to leave and the bartender hollered: "whut'd ya have ?" And you gave the standard answer for the place: "A bump, a beer, and a horsec--k sandwich". With that, you bolted out the door and into the truck and back to work, sliding thru the gate as the whistle to end lunch sounded.

Back up on the iron or perhaps some figures and going over drawings in the afternoon would follow. In those days, no one thought anything of engineers, supervision, and crafts going up on the open iron or going to the taverns for lunch and then back up on the iron. It was the times we worked in.

The old ironworkers used to claim that tying off with the lanyard on a belt made for a false sense of security. They also claimed the lanyard was a royal PITA to manage when they were moving around up on the open steel or trying to "make a point" (get a piece of structural steel hanging off the crane to line up at a connection).

I got to liking riding the headache ball. It was something I never got tired of or scared to do. Maybe there was that sense of security that came of having my foot solidly planted on the "becket" (wedge type wire rope socket above the ball) , or in the hook (on smaller cranes) and at least one hand solidly gripping the wire rope. I blindly trusted the operating engineer running the crane. I figured if he was on the job and had lasted, setting structural steel and boiler parts, he was good. Any operator who was rough with a crane when setting steel or boiler parts would be sent back to the union hall immediately- the other crafts would refuse to work with him running the crane, claiming he was a "cowboy" and unsafe.

We did not get hazard pay. It was part of the job of being an engineer on a powerplant construction site. No one asked me if I was afraid of heights, afraid of tight spaces, sensitive to constant references to sexual activity and certain body parts, or sensitive to guys cussing and yelling, hurling ethinic slurs, and cussing and yelling intially at me. That was the job and those were the times. I stuck with it and for awhile, was as wild and crazy as everyone else.

One time, years later, I was on a Power Authority jobsite at one of our remote hydroelectric plants. A contractor had a crane on a barge, faced up to the dam's upstream side. I needed to get out to the barge to go over the job with the foreman. No way to get to the barge unless someone happened to be in the workboat. I saw the crane operator standing in the sun, and saw how much "stick" (boom) was on the crane. I hollered out, and the crane operator pointed to himself. I nodded my head "yes". I then gave the signal for "use the whipline" (hold one forearm up, tap the elbow of it with your opposing hand). the operator nodded and climbed up to his crane cab. He swung the crane and I signalled him to boom down then swing in a bit, then lower the whip line. I got my foot on the hook, left hand gripping the wire rope, right hand stuck out signal. Another Authority engineer from corporate was standing there saying how I should not be doing what I was going to do, that I was crazy, and similar. I got flown out to the barge, nice and easy. I had not ridden the whipline of a crane in over 20 years, but it was as enjoyable as when I was a young engineer.

Nowadays, it is funny how some things just are readily apparent. I was on a job and the ironworkers were shorthanded, working down in a gate well. They needed the crane (on a barge) to make a pick for them. I happened to be up on the walkway above the gate well. The ironworkers hollered up to me. I had never really worked with this crew, but I guess they figured by my worn work shoes and worn Carhartt coat and scratched hardhat I was OK. I hollered accross to the crane operator, and gave him the signals, including signalling to creep the load down in small increments so the ironworkers could line things up and make the connection. All the while, I was standing on a web of concrete with a deep hole on either side, looking down at the ironworkers and the load, signalling the crane and not thinking about where I was standing. Old habits and instincts, I guess.
 
A VERY good book on the Brooklyn Bridge is David McCullough's "The Great Bridge".
So many facts & figures and detailed info about John Roebling and his son Washington whose passion was building the bridge.

I'm reading it now. I actually bought it for my dad, but he hasn't finished the last book I gave him so he can have this one when I'm done. Great read.
 
A VERY good book on the Brooklyn Bridge is David McCullough's "The Great Bridge".
So many facts & figures and detailed info about John Roebling and his son Washington whose passion was building the bridge.

I concur. That is a great book and so are all the other books he has written. "The Path Between the Seas" concerns the Panama Canal. That is also an epic
story. That was the time in American history when anything was possible.

The Roebling Bridge that crosses the Ohio at Cincinnati was the prototype for the Brooklyn Bridge.
 
And yet again Joe has a very interesting story.
Time he published his memoirs!
Should be a best seller.
 
As I look at those photos, I am struck by the date: 1915. My father was born in 1917, so those painters would have been around during my Dad's boyhood. Chances are working conditions like those shown in the photos prevailed well into my father's adult life. It's hard to imagine that conditions such as those painters worked in were the norm. On the other hand, if anyone has ever seen pictures of sailors aloft in the rigging of a sailing ship, furling or unfurline the sails, the conditions were much the same as what those painters are up into.

I grew up in Brooklyn, and I was seven years old when the Brooklyn Bridge reached its 75th anniversary. Even then, I knew I wanted to be an engineer. My mother and father impressed upon me how Roebling's wife acted as a site superintendent for her invalided husband during the construction. I got books from the public library, nothing so readable or well illustrated as McCullough's book, and read them through.

I walked the Brooklyn Bridge a number of times. In 1982, the Bridge turned 100. I took my then fiance' to the Brooklyn Museum for the exhibition. We spent hours there. I remember reading Roebling's notes, and looking at test reports for materials, and looking at drawings and photos and realizing how little has changed in a lot of the practice of engineering.

Now, I look at projects like the Brooklyn Bridge with a more developed eye. back then, I accepted manual drawing methods as the norm, and I was marvelling at the miracle of the electronic calculator. Now, I look at the CAD and Total Station surveying instruments, and the computer software and think of the legions of people it replaced. I also think of the new and totally radical bridge designs that are spinoffs of suspension bridges. These are designs Roebling would never, in his wildest imagination, have envisioned. At the same time, without today's software and computer modelling programs, those new bridge designs would never be possible.

As I think of the Brooklyn Bridge and my own lifetime, I realize my life's era began with the practice of engineering being not so very different from Roebling's era. We still relied on doing calculations on paper, and if the numbers were ungainly, we used logarithms. We used slide rules to check our work, which existed in Roebling's era, if I am not mistaken. We made our drawings "on the board", and if we wanted prints run, we had to trace the drawings in ink on linen. In the 1960's, the first dry blue line printing machines were coming into widespread use, and the used ammonia to develop the prints. I was in the last class at my engineering school to take surveying using longhand calculations. No electronic calculators. We learned surveying the old way, using a transit, wye level, and worked up to using the theodolite. At Brooklyn Tech HS, we studied strength of materials and we pulled tensile specimens and calculated the modulus of elasticity from the stress-strain curve. It was all done with manual means- taking measurements on the test specimen with dividers and a 6" machinist rule as the specimen elongated. It was an incredible lesson that was such a solid part of the foundation of me engineering knowledge.

When I saw the centennial exhibition for the Brooklyn Bridge, that is when I realized I had started into the engineering profession under conditions not so very different than Roebling's era. Now, when I think of what it was like when I started in the engineering profession and where things have come some 40 years later, it is like seeing a movie that has been speeded up. Some of what is now in everyday use is stuff we would have considered to be the stuff of science fiction or comic books back then. Nowadays, it seems that things move so fast, and things we did fairly directly without too many other parties involved have turned into ungainly nightmares of complexity. Where we took responsibility and went on with the jobs, it seems like nowadays no one can move without all sorts of endless meetings, teleconferences, review cycles, and on it goes. I suppose this is the downside to the increased and rapid means of communication. I think if Roebling had to build the Brooklyn Bridge in today's era, he'd be years before he ever put a piling into the water or did much of anything. Chances are some endangered specie would turn up at the granite quarry where the masonry for the bridge towers was to be quarried, then there would be environmental issues with stirring up the sediment in the bed of the East River, then there would be a row about condemnations of houses in the line of the bridge approaches.... and a lawsuit or two over the fact the bridge would ruin some people's views of the East River and the opposite shoreline.... and then there would be a challenge that the bridge towers and suspender cables would be in the flight path of migratory birds or disruptive to the habits of waterfowl....

In short, Roebling was in the right era to build a monumental new suspension bridge. New equipment and new technology (like working in Caissons under air pressure) could be developed and tried. Jobsite mortality was high, but it was an accepted part of that era. Plenty more freshly arrived immigrant labor was arriving every day. Even when I started in the engineering profession, there was a certain statistic used on heavy construction projects. It was a ratio of project costs to men who would be killed on the job. For every so many million spent, statistically, a man would die in a jobsite accident. Loss of life in the workplace was taken for granted. The picture of the painters bears this out.

Nowadays, any reportable injury is all over the industry internet and is used as basis for safety meetings and additions to company safety policies. I am amazed at that aspect of it. If a person is seriously injured in a powerplant in the USA, we know about it quickly, and we get told to assess our own backyard to be sure we address the same potential hazard if it exists.

A lot has changed in 40 years, and I think the change has been something beyond exponential. Computers drove the change from Roebling's era of engineering to the present day. The development curve was fairly linear and not too steep during the time from Roebling's era until perhaps 25 years ago. Then, with computers coming into widespread use, I think the development curve took off like an F-16 with afterburners kicked in.

What is particularly noteworthy is that the Brooklyn Bridge has endured for something like 130 years, and is in service with today's vehicular traffic- something Roebling could never have predicted or designed for. Whether the bridge was ever re-cabled and whether the bridge deck was reinforced to handle this increased loading is almost a certainty, but the main part of the bridge is unchanged and enduring. Quite a testament to Roebling and the engineering methods he used. What I suspect is Roebling used incredibly low allowable working stresses in whatever he designed, and then threw on huge factors of safety. The result was the basic bridge survives to today's vehicular traffic loading. Had Roebling had today's computer software on hand to design the bridge for 1882 conditions, the Brooklyn Bridge would never have endured to handle today's traffic loadings. The design would have been too "close" or "too exacting". It is an interesting thought to contemplate.
 
Today we came back from a 2 day visit with our daughter in Brooklyn. Although they are working on the Brooklyn Bridge at night these days, when we crossed about 3 this afternoon on our way back upstate I did not see any painters hanging off the wires..........

Joe you are right about how engineering has changed the past 40 years or so. I think any of us who were the last of the slide rule trained engineers have a different outlook on what it takes to get a job done. The mentatlity of design to cost / design life that is the norm these days was not present when we were trained, at least not in the same way.

No doubt the pure calculating horsepower of computers has helped us, but also changed design work for all time. We can get so finite now with life cycles and factors of safety (assuming that what we build matches exactly the design, especially material characteristics) that it takes a different mindset than the way we were taught.

And that is not considering the cultural differences that engineers from other countries bring to the table. My sister has to deal with that in a major way - the stories she tells me scare me to death. I have worked in aviation and how different commercial air carriers / countries / cultures approach that is much the same. My kids understand that even though they are adults I still have a say so on what airline they are getting on if they go out of the country.

I learned the building trades working summers in high school and college for an old time carpenter / general contractor who could do anything. One of the better things that happened in my life was working with him to build the house we live in - it was the last house he ever built before retiring. I know the way he taught me, plus my engineering professors back in the 60s, influences to this day how I look at things. Before I retired we were planning a new building and I was working with the A&E firm on requirements as I was the 'expert' on what we needed. The first question on the first meeting burst the bubble for me - the young engineer from the A&E firm asks 'this is a 10 building, right?' and my dumb look caused him to amplify his question - 'we are building for a 10 year useful life, correct?'. Nowhere in my life would I ever build an industrial facility on the basis of a 10 year life, but that is the way he thought. Now in my other life as an Army combat engineer we did design and build such things - trouble was I was still living in those 10 year buildings 50 years after they were built!

The way design / engineering has changed since 1970 would, I think, totally baffle an engineer like Roebling. The change does not seem to be as drastic when you have been on the ride like we have been - we were part of the change. But he would probably shake his head at what today's engineers don't know how to do that he (and we) considered part of the trade. And yet they can accomplish more, in a much different way.

Joe is dead on as to how time lines have lengthened. Look at how long it took to design the P-47 back in 1941 (?) - something like 100 days. Today you can't even do and RFQ in 100 days, much less design anything!

Dale
 
I am from almost the same time as Joe......Slide rules....I was well into E-school when the Rockwell 4-function calculator appeared, and we got a super deal on them..... Thought they were great.... then suddenly the HP 21 appeared, and did so much more that the Rockwell was instantly forgotten. Maybe I have my times mixed, I went to school in 2 stages, with work in between.... The Rockwell was the first session, the 21 may have been the second. Thermo was slide rule, that much I remember.

Still keep a short slide rule in the vehicles for calculating MPG....

I guess electrical types don't get as many interesting stories... Or maybe they are just different ones, probably less interesting to a general audience.



Joe is dead on as to how time lines have lengthened. Look at how long it took to design the P-47 back in 1941 (?) - something like 100 days. Today you can't even do and RFQ in 100 days, much less design anything!

Dale

Not in the consulting biz...... I may get a week to detail design the first cut control system for a client.... The real time delays are while the client churns around changing plans, changing generators, motors, and mechanical systems. If they wait a little too long to call a halt for changes, we may have their whole control system done.... Has happened more than once.
Then once they decide what they are doing, they want us to be done and providing hardware in 2 to 4 weeks more, including all changes they made, which won't be communicated fully for another week.
 
It's amazing how much impact that one bridge has had. I remember covering it in school when I started studying engineering 12 years ago, which I thought at first was odd seeing as it was "only a bridge". But after looking through some photos of the caisson work and reading about issues with the quality of the steel originally being provided for the cabling I was hooked - truly an amazing accomplishment!
 
As I sit here thinking about the thread and the responses and reflecting on the engineering profession, I have to think of yet another aspect of any engineering job: the working drawings. In the times of Duckfarmer or JST and so many more of us, the working drawings for a project weighed anywhere from a few hundred pounds to tons. The rolls of drawings stacked up like cordwood for most projects. "Drawing Control"- the keeping track of revisions from the design engineering group- was a never ending task. A couple of people in field offices were usually tasked with nothing but "drawing control", removing "void" drawings from the "sticks" and flat file drawers and replacing them with the latest revisions of the drawings. Obsoleted drawings were kept "for the record" in some cases, so the sheer volume of drawings got to be huge. Then, there was the whole matter of getting a "field change" onto the "record drawing". A "marked up drawing", attached sketches, calculations, and other documentation went back to the home office- vis UPS or US Mail. The drafting department there had to take the original, get the electric eraser, and make the changes, drawing them in manually. At least the originals were in pencil on drafting film, not inked.

Now think of this day and age: CAD. It is instantaneous. Want to update or revise a drawing ? It is done electronically. Very few "sticks" of drawings are in use and certainly nowhere near the volume of paper record prints. It's a revolution that defies my own imagination based on the times I came up in. Roebling's notes and sketches are not so very different than my own engineering notes, calculations and sketches. Want something more scary ? Engineering firms have taken to sending their work electronically offshore. Got a job going on in the USA and need design and drafting done ? A US A/E firm may well take the job, and have a staff presence in the USA. But, as soon as the job gets rolling in any depth, the design and drafting is done offshore. Some is done in India, some in the Phillipines. The claim is it is "cost effective" and more efficient. If an engineer in the US makes a field change to a drawing, it is sent electronically to the offshore offices. About the time the engineers in the USA go home for the day, the engineers and drafters in the offshore offices are first clocking in. They do the design and drafting for the change, send the revised drawing out electronically, and the US engineers get it first thing the next morning.

It all sounds good in theory. The proof of how this sort of thing can go awry came at a powerplant. The A/E firm was in the USA, but had an office in India for the grunt work of the actual design calculations and the design and drafting. The drawings arrived, the work began, and all was right with the world for awhile. As the job progressed, one of the client's field engineers noted a plant cooling water line was run against an uninsulated metal exterior wall (engineered steel building). The line itself was uninsulated steel pipe. The US site engineers told their corporate staff they had spotted a problem. Of course, the answer was: "We are paying the A/E, and they have full responsibility... " In short, don't second guess the A/E. So, the plant went to completion and was commissioned in warm weather. Come that winter, the cooling water line froze and there was a forced outage. Now, everyone is probably saying this should have been obvious. Problem was, it was obvious to people in the USA, we know what winters in the Northeastern USA are like. People in India do not. They ran fine calculations for heat balance, piping friction losses, designed the piping per the latest edition of the Power Piping Code, and all else. A lack of basic knowledge or consideration of winter in the Northeastern USA was their Achilles heel.

The quality of steel is still an issue. Roebling had vendors running in substandard steel for cable strands. Nowadays, we find that basic grades of structural steel are "all over the map" as far as ductility, weldability, and strengths. Despite the most advanced methods of melt analysis, and greatly improved methods of steelmaking, the consistent quality of basic structural steel has gone downhill. I attribute this to a combination of things, not the least of which is the death of the conventional steel industry (Rick Rowlands take note). In the days of blast furnace based mills, we had what I call "new steel"- steel made from pig iron with a limited amount of scrap steel in each heat. Now, we have "remelt mills" using electric furnaces and they start with "processed scrap". The result is so many "tramp elements" of varying amounts in each heat that the physical properties and weldability of structural steel varies widely from one heat to the next. Even the corrosion rate of the steel coming out of today's remelt mills is way higher than the steel from the old traditional mills. Roebling probably was getting steel for the cable strands produced by Bessemer process. It was a one-shot kind of process, no chance to modify the contents of the heat once the Bessemer converters were "in blast". The steel produced was a very low carbon, "plain carbon" steel. For drawing into wire, it was ideal. It was a very ductile steel, as long as the phosphorous and sulphur content did not get too high. This was probably where Roebling had issues with certain lots of the steel. At best, Bessemer steel was not particularly high strength, and owing to the wide range of properties, Roebling designed accordingly. Roebling worked with what he had at hand, and he allowed for expectable variances in strengths or in material quality. If Roebling tried this same school of design today, he'd be out on the street looking for work.

In my own time as an engineer, I've seen the shift from Allowable Stress Design (ASD) to Load Resistance Factor Design (LRFD). ASD is basic strength of materials, very straightforward design method. It is what I came up with. LRFD is another story. It reduces the amounts of materials required to build a structure by the use of factors to determine how often and how much the maximum loads will be applied. LRFD results in structures being built with a lot less material in them than an equivalent structure of even 20 years previous. I am an ASD engineer, an oldtimer. I've bought a steel design text on LRFD to satisfy my own curiousity, but I have no need of applying it. I use ASD, and very basic methods when I design any sort of structural elements, not any different than Roebling's methods. As a side business, I do some consulting engineering. As such, I get called upon to evaluate or design structures made of rough-sawn ungraded lumber. NYS allows the use of ungraded lumber from local mills to foster a local forest product industry. When I get a job using rough cut lumber, it is basic strength of materials. I take the minimum strength of the lowest grade of pine or hemlock, knock that value in half, and then use that as my maximum allowable bending or tensile stress. A lot of the jobs involve evaluating roof trusses for barns or homes. These are built of some pretty hefty rough cut. I analyze these trusses the same way people have analyzed trusses since probably the middle ages. Method of pins or method of sections, depending on the truss design. Like Roebling, my calculations pile up in an old time handwriting with sketches of elements of the structure being evaluated, done on paper, in ink. No software. It is an interesting perspective to span so much change in engineering. I might photocopy or FAX the calculations, I might email the various parties involved in the job, but it all starts with engineering methods not any different than Roebling used.
 
Apparently all of the drawings for all of the NYC water supply aqueducts, starting with the original croton dam and aqueduct, were
retained and stored in a second-story warehouse above a NYDEP garage somewhere in manhattan. The files were so disorgainzed
by being shuffled around over the years that there were actually *maps* made of the warehouse to identify where various
project data were stored.

The warehouse was not climate controlled and many of the drawings has begun to degrade. A project was created to
try to recover and copy as much as possible - there is a book out about that project.

Evidently there were some large, detailed, vintage maps and prints that were missing from the collection. The word was
put out about what was going on to archive things properly, and many of those items mysteriously showed up. There
was a good chance that they had been 'pilfered' from the stacks of paper because they were recognized as being important
historical documents, and they were being allowed to compost in place.

Interesting book that was.
 
Jim:

You are correct about the NYC DEP drawings and documents being stored in haphazard and scattered fashion. It is not just limited to locations in NYC. Many of the upstate watershed buildings were also repositories for documents, photos, record books, core borings, sample submittals... In 1981, I reported for work at Kensico Reservoir. The NY Power Authority was putting a little 3-unit hydroelectric plant in the "Lower Effluent Chamber" in Valhalla, NY. I was it for the Power Authority site presence. I soon developed a great working relationship with two very fine engineers from NYC DEP, and one great civil engineer from NYC Board of Water Supply. These engineers showed me bound volumes of construction photos taken all over the Croton and Catskill systems. There were construction records, and "Reports to the Commissioner of Aqueducts" going back as far as 1885. I really enjoyed looking at these documents and photos. The engineers told me a lot of this sort of stuff was stored in crates in the "air remover" buildings along the aqueducts, just there for the mice and time to destroy. They also showed me boxes of glass plate negatives of construction photos they had rescued.
It was quite amazing, realizing some of the photos were taken in adits (aqueduct "tunnel headings") using arc lights and flash powder on glass plates.

At Ashokan, in the lower gate chamber, we were tying in to supply penstocks for a two unit hydro plant. In the Lower Gate Chamber, there was this "roller map". It was a wooden box with a glass window, and a pair of hand cranks at the top of the box. You started cranking and there was a continuous drawing showing the hydraulic gradient, the actual elevations, as well as cuts and sections of the aqueduct and structures. It began at Ashokan and ended in Silver Lake Reservoir on Staten ISland. The drawing was done in India Ink, by hand, on some sort of treated linen or cloth. Elevations and sections showed the aqueduct where it was tunnelled in rock or cut and cover, showed weep drains, access shafts, and various gate chambers along the way where communities tapped the aqueduct. The most interesting part of that roller map was the details of the Catskill Aqueduct crossing under the Hudson River at Breakneck. The aqueduct dropped into a shaft on the west shore, and that shaft was 1600 and some odd feet deep as I recall. This was to get the aqueduct into sound rock, free from faults. The aqueduct then bored thru the rock to a shaft on the eastern shore at Breakneck. The aqueduct actually pitched down a slight amount on the run under the river, then came straight back up in the shaft at Breakneck, making a siphon. I also saw original construction photos of the taking of core borings in the bed of the Hudson river. This was done to determine where the sound rock lay. From the borings, faults in the rock were found. The core borings were still kept somewhere on the line of the aqueduct. I saw some in the coal bunkers at Kensico.

Years later, a lady named Diane Galusha was writing a book called "Liquid Assets", the story of the NYC watersheds and water system. Ms. Galusha had asked the division engineers on the Catskill Division of the watershed to help and edit her book. I suspect my old colleagues on the watershed remembered me, as they recommended me to Ms. Galusha to help edit the book. She had heard I knew something of the engineering and construction practices of the bygone days when the Catskill Watershed was built, and asked me to help out. It was an honor I thoroughly enjoyed.

Whatever is coming to light in the way of prints of old NYCDEP construction photos or drawings is the tiniest tip of a very huge iceberg. What has to be remembered is very little on NYC DEP projects in the era of the Catskill watershed was ordered as "stock". Even the locksets on the big entry doors to the watershed buildings were heavy cast bronze with NYC Catskill Water Supply cast onto them. Every single sluice gate or valve was designed by NYC engineers and was extra heavy. All the valve and gate operators were custom built with huge bevel and crown gears, lineshafting, clutches, and custom made position indicators with custom made limit switches. Nothing was remotely light or off the shelf, so there were tons of detail drawings and specs. Then, add tons of construction contracts, construction cost accounting records, material test reports, and you can imagine there are literally tons of documents and submittals and core borings out on the watershed, yet to be unearthed.
 
If I recall correctly, wooden supports were used in the caissons, and in one of them a fire burned out a portion of the already installed supports. After the fire was out, concrete was pumped into the voids created b the fire.
 
I did not know there was a hydropower installation at kensico. Interesting.

The book you mentioned, that might be the one I was reading. "Liquid Assets" might be the name of it
but I'd have to check with the resident librarian.

I was aware that some municipalities tapped into those aqueducts (the montrose improvement
district being one of them) and was not certain how that setup was permitted or regulated.

And the siphon that comes out at breakneck - I think those two siphons (for the delaware and the
catskill both) are some of the most amzing bits of engineering I've ever imagined - and also some of the
most vulnerable, and given today's american technology capabilities, some of the most non-reproduceable
engineering I could think of.

There was a photo in that book of the building at the breakneck riser - and they had a forged steel
cap that went on top of the riser, which was held on by a ring of bolts which were pre-tensioned with
an hydraulic porta-power (extra large version) with the protruding studs which had been cast into
the concrete surrounding the riser.

I am *positive* we could not make that forged dished head again. I also doubt we could even make
the darn bolts that hold it in place!

This, with the idea that the entirety of NYC depends explicity on evey ounce of engineering that went
into those aqueducts. And would rapidly cease to exist as we know it, without them.
 
Jim:

The hydroelectric plant at Kensico was envisioned during the design of the Catskill system. In 1915, when the Lower effluent Chamber was built, there were three (3) flumes for three (3) "open flume Francis Turbines" of 1 Mw each. There was also a smaller flume for a "house turbine" of perhaps 100 Kva. In 1915, when the Lower Effluent Chamber was completed, sluice gates were installed on each of these turbine flumes, and the gates wedged in the closed position. The draft tubes were all cast in concrete, all tied into a common tailrace which connected to the aqueducts. In 1915, having no immediate need for the turbines and generators, the watershed engineers had a temporary concrete floor with breakout slabs poured over each of the flumes. The space was then used for a maintainence machine shop, until an agreement was made with NY Power Authority to develop the hydroelectric site at long last. 65 years later, I arrived on site there, and we demolished the partition walls that had contained the shop (previously emptied), and removed the breakout slabs. Like a time capsule, there were the flumes and sluice gates waiting for us. We put (3) open flume Franics turbines in, each driving a 1 Mw induction generator. The house turbine idea was deemed impractical by the powers that were, and we poured another floor over that flume opening and put a load of electrical switchgear there. Now, 30 years later, Kenscio hydroelectric plant is to be decommissioned and the equipment removed. The word is the new configuration of the aqueducts (new tunnels into NYC, new valve chambers) has made the Kensico plant kind of off the normal flow path. The other thing that used to happen was huge numbers of Canada Geese found open water by the gate house on Kensico Reservoir each winter. This resulted in massive amounts of goose s--t in the water, which happened to be at the intake for the hydroelectric plant. The tailrace of the hydro plant went right back into the NYC Catskill Aqueducts. Even with chlorination, the coliform levels and other bacteria were beyond acceptable limits. The result is Kensico Hydroelectric plant used to be off line for a few months at a time due to the goose s--t problems. Now, the word is that it is to be decommissioned and the space re-used by NYCDEP for some other purpose. Strange to think that the hydro power project I started with my career with the NY Power Authority with will be retired about the time I retire as well. I always figured when we built hydroelectric plants, they would outlast all of us put together, not be decommissioned and retired ahead of us.

The materials used on the NYC watersheds were irreplaceable in today's world. As an example: the sluice gates had solid bronze stems, 6" diameter x 30 ft long, with a single-lead acme thread and long keyway cut over the top 10 ft of each stem. The gate operators were unbelievably massive. IN 1948, the Delaware Aqueduct was connected to the Catskill at Shaft 18. A series of electromechanical gate operators were designed and built for the job. Each gate operator was made of cast steel, looked like a rocket with a large flange mounted motor as the "nose cone". Each gate operator had deep gear reduction, and turned a nut that raised or lowered the gate stem. To seal the gate stem threads and keep lubricant in the gear case as well as surrounding the upper part of the stem threads, some brain decided to use a "mercury seal". This was a tub of liquid mercury with a hole in the middle and "stovepipe" like a coffe cake pan. This was filled with liquid mercury and the mercury was just a bit higher than the center stovepipe in each pan, so formed a liquid seal around the stem. The gear lubricant was lighter than the mercury, so no chance of displacing it. These gate operators went beyond massive, and worked without a problem. In the 80's, someone discovered the liquid mercury seals. Instead of thinking how they might use a more modern elastomer seal or something halfway rational, they decided those special gate operators had to go. In their place, "Limitorque" geared operators were installed. It was a visible joke. The Limitorque operators, which were heavily rated by Limitorque standards, were tiny when compared to what they replaced. The Limitorques were high maintainence. I am not sure how things ever were solved there, probably by ripping out the gates or valves the original mercury-sealed operators worked and putting in something "modern".

The watersheds were designed to last 1000 years given any decent maintainence. During the reign of NY Mayor John Lindsay, the old line engineers and mechanics on the watershed began to retire. These were men who had been there when things were built. Instead of replacing these men with more engineers or mechanics at the upstate sites, Lindsay's administration went on a binge of creating "deputy commissioners". This was political payback to cronies and friends of cronies. NYC got plenty of deputy commissioners, and not only were the engineers and mechanics not replaced, maintainence and capital expenditures were deferred on the watersheds. Things were literally run into the ground and patched together in some locations.

To give an idea of how hard it is to duplicate materials in today's world: recently, at one of our own hydroelectric sites, a regulating gate had a cast iron upper gate guide break in service. This caused the gate stem to bend badly. The stem was furnishe din 1989, and is 3 1/2" diameter x 30 ft long stainless steel, with the stem threads and keyway machined on it. No mills are producing this sort of material in mill runs, and it would have to be special ordered. The closest material available was about 12" shorter, so we had to make custom shorter upper gate guide sections. A lot of what was available from the jobbers even 25 years ago is often hard to come by, if not impossible or cost prohibitive today.

Joe Michaels

Alchymist: you are correct: there was a fire in the caisson during the construction of the Brooklyn Bridge. The caisson was made of timber. The fire was put out, IIRC, by the NYC fire department flooding the caisson using fireboats pumping water down the access shaft. The fire was particularly hard to deal with due to the increased air pressure within the caisson, and it burnt into the various courses of timbering on the top of the caisson. Roebling came up with what amounted to a pressure grouting method to try to seal and stabilize the damage. This was a method of injecting a sand-cement grout into the joints into holes drilled up into the timbering, forcing the sand-cement grout into any voids in the timbering.
The Brooklyn Bridge towers are founded on the timber mats that were the tops of the original caissons.
 








 
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