^ It does give a feeling that things are going slow. But it is supposed to be something like 22 viaducts, and at least 1 (probably 2) lengths of trackage along that entire length, over 7 years - so I guess they have to pace themselves nice and slow (?!?). I am curious why, in the space of the time any Olympic Games awardee city is given to build all of its necessary stadiums and transport systems, we can barely get 4 miles of low-intensity commuter rail refurbished.

a) there's no particular deadline so work can be spread out longer to make it easier to pay for

b) building a new line, while having its own set of issues, can usually have more things done at once because it doesn't have to worry about continued operations of the service

Because in other cities service and economy are the priority factors.

In the Chicago area protecting your "Childish Transit Fiefdom" is FAR AND AWAY the MOST important factor in ANY (Transit) decision: http://www.chicagotribune.com/news/l...,3371081.story

If there no particular deadline why are they doing it at all? I liked the look of the vintage riveted bridges alot! Plus, there's probably 1000's of railroad bridges around Chicago all the same age why aren't any other ones being replaced? I thought these ones were being replaced for higher truck clearances, but they seem to be the same height as the new ones so why bother. Just give them a new coat of paint.

As I recall Metra's logic was that eventually the maintenance cost of keeping the existing bridges in sound condition would exceed replacement cost in the coming years. They opted to start replacement with a generous time schedule to keep costs down since the existing structures are still serviceable. They are rebuilding old retaining walls/abutments as needed too. The reconstruction will also pave the way for adding a 3rd track back to the line.

Well, initially they were willing to throw away the third track.

Three-track operation could allow for a limited S-bahn type service to Evanston. The UP-N is really the only mainline besides Metra Electric that is lined with dense residential neighborhoods, so it's a natural candidate. It would also act as a second rapid transit line to the North Side.

Most masonry buildings don't have any particular deadline for tuckpointing and deteriorating stone replacement, but if your house needs it, you schedule it and do it. That's what maintenance is.

They had deteriorated to a point where repairs would be expensive. The newer designs are better and will last longer

To be fair, I see they are indeed doing a great deal of work on the retaining wall and rebuilding the earth fill structure between (and beyond) Wilson and Irving Park.

But why the wooden retaining planks? Are they temporary (e.g. forms for concrete pour) or are they treated to never rot, ever?

Has Metra or UP said they would have 3 tracks at the end of this project, or just that the trackbed, including viaducts, would accommodate the laying of a 3rd track if desired?

Also, the thought of 3-track operation is exciting (if presently unlikely), even if it terminated at Peterson (the northern extent of this construction project) or Ravenswood. Under an S-bahn scenario, would electrification be the only practical choice, and if so, would third-rail power be more likely (cheaper buildout and maintenance) or less likely (hazard to workers maintaining the other 2 tracks) than catenary power?

Could be any number of things. Certainly if the wood lagging is used as formwork for a sufficiently-reinforced concrete pour, the wood can be left in the ground indefinitely. I don't know the lifespan of treated wood in underground conditions, but it doesn't matter since the wood will serve no structural role. Alternately, Metra may be using a precast concrete panel between each steel soldier pile.


Not even that much. There will be space for a third track within the ROW, but not the viaducts and probably not even a full trackbed. The future third track will take the place of the current southbound track along the east side of the ROW.

Regional rail/s-bahn doesn't require any kind of electrical power system necessarily. If I were running the system, I'd spring for an FRA waiver to run lightweight DMUs, and construct high platforms. Getting a waiver shouldn't be a problem since the UP-North line sees no freight traffic.

^^^ I’ve seen some midday freight movements at the Elston & LeMoyne yard, but those can likely be rescheduled.

I’d also say that Metra’s heavy staffing is a much bigger obstacle to higher frequency than rolling stock.

I think those freights arrive at Elston/LeMoyne via the UP-NW line. You're right that there is a trickle of freight traffic on the shared segment, though. Seems like a creative/inexpensive combination of track design and scheduling should allow lightweight, high-platform service to coexist with the trickle of freight traffic.

From today's Trib. . .

CTA, Pace will share new fare card, beginning next summer

So...what happened 3-days pass? Is that no longer existed? When it happening? I usually ride on Chicago Transit by last year. I took on Blue Line from ORD to Clark/Lake Station. When they did change it?

There are of course many good reasons to get a waiver and buy lightweight trains, but performance-wise, you're better off with an M8 or Silverliner V than with a noncompliant DMU. Diesel limits your acceleration and speed, and doesn't really belong in a large city with frequent stop spacing.

M8, Silverliner, or any EMU, will not work without electricity, whether from an overhead catenary wire or third rail. The fact remains that most LIRR corridors to the easternmost points don't have electricity available to power EMUs, and LIRR isn't planning to electrified them.
So the question we should be asking is whether DMUs can be faster than diesel power locomotives and coach cars? I believe you'll discover that DMUs are faster.

Its on the low side of the list of things...but its there...

While I agree, I think flexibility is the key to get Metra to accept a regional-type service. S-Bahn service running to Evanston would use rolling stock that is compatible with the entire line up to Kenosha. Plus, Metra's been exploring the use of DMUs for awhile now.

I'm all in favor of electrification but a capital project combining a third track, a set of DMUs, and a set of new platforms is an order of magnitude cheaper than one that includes electrification up to Kenosha. Maybe about $300 million vs. $2-3 billion, using costs from MBTA's Fairmount Line and Caltrain.

^ Wasn't there a proposal for service on a Chicago Belt line which was out west aways say towards Aurora?

Instead of creating an s-bahn style system, why not fix the purple line and run an honest express route. It would serve basically the same purpose and with a route through the subway, probably would take the same amount of time.

I was hoping somebody had an answer to the wooden board question but I guess we will have to wait and see. There are two different types in each section, the lower section is horizontal, a middle vertical section and the upper section is horizontal. So why the difference?

The bridges do provide additional clearance but it is not much. I estimate about 4-6 inches difference between the old bridges and new bridges although I have not climbed up and measured.