So for the past couple of weeks, they have been tearing up Division St from Roughly Cicero to Kedzie and repaving it nice and smooth. I have noticed ina few locations where the old brick is showing through and decent evidence of the rails that the trolleys used to roll on. I think you can still spot it between Cicero and Pulaski, but also I have seen a spot on Division just west of Cicero between Lavergne and Lamon, in the east bound lane you can see a strip of bricks sticking through the asphalt. Its right next to the concrete bus stop pad. Check them out if you can!
You'll find those tracks under a lot of streets. They we left in place as they act as a current return for the el system, so traction current doesn't cause corrosion of water and gas mains.
Jeff_Weiner Wrote:
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> You'll find those tracks under a lot of streets.
> They we left in place as they act as a current
> return for the el system, so traction current
> doesn't cause corrosion of water and gas mains.
davey7 Wrote:
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> How would they act as returns for the el?
>
> Jeff_Weiner Wrote:
> --------------------------------------------------
> -----
The return circuits for the traction current on the el must be isolated from the ground. A lot of the substations that serve the el system also provided power for the streetcar system, so the tracks, which also acted as a current return for the streetcars, were left in place. If they must be removed, cables have to be installed to take their place, otherwise the current follows the other conductive items under the streets, namely the gas and water mains. This cam cause corrosion and leakage. It's something I learned when I started working for the City as a traffic engineer back in 1983.
davey7 Wrote:
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> How would they act as returns for the el?
>
> Jeff_Weiner Wrote:
> --------------------------------------------------
> -----
The return circuits for the traction current on the el must be isolated from the ground. A lot of the substations that serve the el system also provided power for the streetcar system, so the tracks, which also acted as a current return for the streetcars, were left in place. If they must be removed, cables have to be installed to take their place, otherwise the current follows the other conductive items under the streets, namely the gas and water mains. This cam cause corrosion and leakage. It's something I learned when I started working for the City as a traffic engineer back in 1983.
rjmachon Wrote:
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> I have seen these tracks torn out on Clark Street
> years back when they repaved the streets.
They can be removed when they are found to be unconnected to the current return, like in areas far from the el, or where the CTA put in cables as part of an upgrade to the power distribution system. Another reason to leave them in place is because they are so big: the rails are tall, called "girder rail", to minimize deflection when a streetcar rolled along, to keep from damaging the pavement. It's even a bigger headache when old cable car troughs are encountered, as they are bigger and heavier than the rails.
I would have thought that the el was totally separated as a circuit since the current would have had to travel through the pillars down through the ground to the streetcar tracks (or through the embankments or up from the tunnels).
My suspicion was it was just cheaper to leave the tracks in place...
In my travels today I noticed tracks sticking out of the asphalt in the roadway that's just south of 63rd St heading east from King Drive over to Vernon. It looks like that was a turn-around for the streetcar.
It must have been a busy transit area when the White City Amusement Park was in full swing.