Leads for Extension at NCR?

Hello,

After riding by New Carrollton on the NEC many times and studying satellite images I have began to wonder how those extension leads would (and possibly still could) work. They seem to exit the platforms of NCR on the north end and have some interlocking and some diverging switches for the yard off to the right. Then they seem to go straight a little bit and then start hugging the curve of the NEC. The track innermost towards the NEC mains seems to stop about 3 cars short of where the outside track stops.

So what is the reasoning behind all of this.

They also are going upgrade. Was it reasoned that they might go curve up and over the NEC and then pop into a tunnel on the other side? Looking at satellite images there really isn't a lot of room on either side of the tracks to build.

My assumption is that they would have built up and over the tracks (why else an ascending grade?) and then somewhere on the other side they would have ducked into a tunnel until they where in a less dense area they could pop back out in.

Any thoughts?

Davis

"strench707"
After riding by New Carrollton on the NEC many times and studying satellite images I have began to wonder how those extension leads would (and possibly still could) work. They seem to exit the platforms of NCR on the north end and have some interlocking and some diverging switches for the yard off to the right. Then they seem to go straight a little bit and then start hugging the curve of the NEC. The track innermost towards the NEC mains seems to stop about 3 cars short of where the outside track stops.

So what is the reasoning behind all of this.

Typical end of line tail track length. The staggering of their length is because of the configuration of the yard lead interlocking. The turnout to yard lead track 1 from track D1 is further east compared to the crossover between track D2 and track D1 to the west.

They also are going upgrade. Was it reasoned that they might go curve up and over the NEC and then pop into a tunnel on the other side? Looking at satellite images there really isn't a lot of room on either side of the tracks to build.

Typical metrorail surface stations are level or on a .035% grade to accommodate drainage. The NEC is on a continuos upgrade heading east/north with slight increase in the grade east of the Amtrak station.

My assumption is that they would have built up and over the tracks (why else an ascending grade?) and then somewhere on the other side they would have ducked into a tunnel until they where in a less dense area they could pop back out in.

It is my understanding that an extension of the D Route Orange line would run on the surface parallel to the NEC on the south/east side.



You may have noticed that there is an unused trackway that bypasses the New Carrollton station platform on the south side. This unused trackway is to accommodate a future extension of yard lead track 2 to mainline track D1 west of the New Carrollton station.

Okay but why do the tracks go up an incline. If you look at maps of the area there is zero room to accommodate a WMATA RoW. Maybe it was feasible back in the 70's before current developments but now I don't see any way they could squeeze it in.

Also for that empty trackway, why haven't they built that? Wouldn't it make it easier for trains in the yard to get around the platforms if there was an additional track. If a train needed to get out and both tracks were occupied then they would need to move one of the trains out of the station.

Davis

Right now, it makes sense not to have it. Currently, and for the foreseeable future, New Carrollton is the end of the line. Thus a train entering service from the yard would need to service New Carrollton anyway. Now if they ever extended the line beyond New Carrollton, it might be worthwhile to have as a way of entering the yard from Track 1 with New Carrollton as a through station. But right now, I don't see the need for it, and it would be something else to maintain that receives little to no use.

"strench707"
Okay but why do the tracks go up an incline.

To gain altitude. I don't know if you are old enough to remember the old Beltway Train Station. That facility use to be where the SHA yard is at the north end of Cobb Road. The NEC tracks are roughly 15' higher in elevation there then they are at the New Carrollton Station, another 5' more just outside the Capitol Beltway.

If you look at maps of the area there is zero room to accommodate a WMATA RoW. Maybe it was feasible back in the 70's before current developments but now I don't see any way they could squeeze it in.

The Amtrak NEC easement is wider then it appears in those aerial view maps. The property line is roughly 30' to the outside catenary towers over most of it's length in State of Maryland. WMATA would need no more then 6' more for their 2 tracks. No modification would need to be done to the decks to the Beltway and Annapolis Road bridges to get the WMATA track under them. They would pass between the abutment and the columns on the south (Beltway) and east (Annapolis Road) ends of those bridges. The same method was used to get the yard lead track under the Beltway in Greenbelt.

"SchuminWeb"
Right now, it makes sense not to have it. Currently, and for the foreseeable future, New Carrollton is the end of the line. Thus a train entering service from the yard would need to service New Carrollton anyway. Now if they ever extended the line beyond New Carrollton, it might be worthwhile to have as a way of entering the yard from Track 1 with New Carrollton as a through station. But right now, I don't see the need for it, and it would be something else to maintain that receives little to no use.

My thinking for the reason for the bypass track is to allow movements from the extension in and out of the yard without fouling the mainline track at the New Carrollton platform, much like the pocket track at West Falls Church is used to get trains in and out of Falls Church Yard that are heading to or coming from Vienna.

Why do you think they haven't added the bypass track already? It seems like it wouldn't be that much more to maintain and its just vacant roadbed right now?

Also, where did Metro think they could go in Bowie? The wye to the Popes Creek Secondary would have to be bridged over but there would be no room to descend since the north leg switches back into the NEC mains under a bridge. If they bridged over it would block the view of the old RR museum and kinda ruin the look of the town.

It would seem that WMATA would have to ditch the NEC RoW to get near enough to be useful to Bowie if they ever extended.

Davis

"Bowie" the area where the Pope's Creek Sub meets the NEC is referred to as "Old Bowie" by locals, and is really nowhere near "Bowie" where people are actually interested in going. If the Bowie area is to be served, it makes far more sense to extend the Blue Line along MD 214 (Central Ave) into the more populated part of Bowie. The orange line extension would be better served sticking with the NEC RoW to serve Odenton/Ft Meade and then BWI.

That make sense, also the Blue would be more alligned to go to Annapolis from there as well. I live in Annapolis and I know a lot of people would use it if it came out here. Most people drive to NCR or Largo. NCR more though since Largo isn't exactly the safest at night.

Davis

strench707 wrote:Why do you think they haven't added the bypass track already? It seems like it wouldn't be that much more to maintain and its just vacant roadbed right now?

Short answer: Because right now, it's not necessary, since the yard is at the end of the line. Terminate at New Carrollton, and go into the yard. Likewise, come out of the yard and start the run at New Carrollton.

If New Carrollton ever became a through station rather than a terminal due to an extension of the line, then the bypass track would become necessary to allow movements in and out of the yard without getting in the way of mainline traffic, similar to the way the center track functions at West Falls Church.

Ah okay that makes sense, I thought they would have added it anyways just as a backup track, like if they were replacing a platform track or one was closed for some other reason they would just have the capacity to run around that.

Davis