This is one of my favorite pictures of all time, because it shows so many things, both obvious, and not so readily apparent.

It is a section taken out of a piece of pipe that became a problem during a swabbing operation, since the swab would not pass the obstruction in the pipe.

This pipe at one time had a type of service connection that was not actually tapped, nor did it have a saddle.  The pipe was simply drilled on tthe top, and a tapered main stop was driven into the drilled hole, forming a press fit.  The main stop incorporated an elbow before the actual valve, to provide a hammering surface, as well as restraint in some cases, because many utilities would put a boulder on the top, which then would act as a sort of thrust block.

These often would blow out later, for many reasons, and that is what happened here.  The repair sequence was as follows:

1) drive piece of 2X2 into the hole left by the old service

2) Trim said 2X2 off flush with pipe

3) Install piece of rubber tire to make seal

4) use piece of valve box as a backing plate for the tire

5) Use service saddle to clamp whole works together.

Now when I show this picture in training sessions, everybody laughs about hillbillies, etc, because this town is somewhat remote.  But actually, this is quite a marvel of repair clamp design under emergency conditions….

The major leak is staunched, a gasket of suitable durometer and tensile strength is selected, a backing plate is located of suitable geometry and strength, and finally a clamping load is applied to compress and preload the gasket.  Nothing to sneeze at under emergency conditions.   The effectiveness of this repair is evident actually, since it held up for decades.  Indeed, it was only found because the swab jammed up against the 2X2.  You can see that the ultimate cause of failure would likely have been failure of the saddle bolts from corrosion.

Of course, don’t try this at home kids….DWQMS, NSF, AWWA, among others would have lots to say.  Still, you have to admire the operator’s ingenuity in the face of poor inventory control.

Aside from the above, there are some other neat things about this picture that I’ll discuss in a later post.

When testing a hydrant, one is often presented with choices.  In this case, flood out the Bell pedestal, flood out the hydro box (zap), further erode the soil, or set up a bunch of equipment.  (Skipping it altogether is usually not the wisest choice.

One always should take a “before” picture in a case like this, so you don’t get blamed for it “after”.

Who put that there?

Gasket creep can be caused by excessive pressure, excessive clamping (squishing the gasket), or slow creep over time.  It can also be caused by chemicals in the water changing the pliancy of the rubber (turning it to mush)-think chloramines.

In a fire hydrant, the valve disc can creep to such an extent that the hydrant becomes difficult to disassemble, because the gasket flows out around the valve seat.

One can minimize this by not overtorquing the hydrant shut (don’t reef on it!), changing the disc periodically, etc.

Modern synthetics offer us lots of opportunity to play around with different rubber also.

Additionally, there are other things that have been tried, like this.   This is a composite hydrant valve disc, made up of a sort of fiberglass netting, glued and/or filled with resin of sorts.  You can see that it has delaminated under a high flow, and is therefore not a very successful design.  This was shown to me by my friends at the Ottawa Water dept., and I took this picture.  I have never encountered them anywhere else.

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Took this at my camp on Whitefish Lake near Parry Sound yesterday.   Snow is on the way.   We got something like forty cm over the weekend.  Pretty, but I didn’t shovel it……I just left for Ottawa instead.

The little section above is taken from a larger sheet of hydraulic graph paper, that I cut and pasted many years ago. (yes, with scissors and paste)  Have used it for many years, but was unable to find a clean source for this type of paper.   It is a type of semi log paper, with the flow scale on the bottom raised to the exponent 1.85.

The program Dplot, can produce this type of paper cleanly, but last time I check, Excel could not.

Hard to believe, eh?

Egg McMuffs for breakfast, and crap for lunch, and by the time dinner comes, your body needs a fix of vitamins that you aren’t going to get from fast food.

A good chinese restaurant will provide your body with the essential nutes.

In Ottawa, I have had great luck with the Dragon Bowl on Cyrville.  They deliver to St. Laurent, which means Comfort, Chimo, and Hampton.

They need an on-line menu.

One time I was in the Travelodge on Carling, they told me to order from Ho-Lee-Chow.  It was horrible, greasy and cold.   Now I don’t stay there anymore, nor would I ever order there again.  Apparently, I’m not the only one, since the chain has gone tits, although the local one is still serving.

Fresh, beef tender, veggies crisp, and you can spec your spice level.   Generally fast also.

Only one blah experience, and it was still 6/10.  Usually it’s 9/10.

This job went on for a while and all through construction, nobody thought about putting an extension on this poor hydrant.  Now it will be expensive to go back and a pain in the neck.  I can imagine what the top of the hydrant would do to a car running over it.

Not to mention that this hydrant is borderline unusable, and its normal breakaway features have been nullified.  You have to assume that the auxilliary valve is under the curb.  Somebody’s wallet is going to throb on this one.

The only thing worse than working in the mud,  is when it freezes.  The picture above shows a launcher for large diameter swabs, pumper trailer and a water truck, all needed to launch the swabs into the pipe so it can be swabbed.  Launching swabs is better than simply placing them in the pipe during construction for a number of reasons:

You can examine and account for each swab as it is launched.

You can launch into a fully loaded pipe, so that the cleaning power of the swab is enhanced, and the speed of travel can be controlled, unlike in a dry pipe.

You can space them, which means each individual swab is more efficient in cleaning.

Unfortunately, when conditions aren’t exactly optimum, it can be a costly means of proceeding.

Thanks to KB for the pic.