Deciphering ICC Valuation Maps

[Kurt Maechner]

I'm wondering if anyone can decipher a few terms on my C&S Valuation map.

What would the following be:
1. This type of designation is where the line crossed a stream:
1803+04(small o raised up here) 12' X 12' Box 18' -
-my guess is a culvert?
-sometimes there is a "W" before the "Box"
-others spots of "Open Box" or "Stone Box" or "Wood Box"

2. Curves
What does P.T. and P.C. mean?-related to curves-PT is at the beginning of the curve and PC at the end

3. A triangle shape is used in several spots too.

4. Rock walls have dimensions such as 1 X 5 X 52.  Is that width, height, length?

5. At a water tank (Tunnel Gulch) it says 1776+22 (small raised o) 15 W. Tank
What are the numbers referring to?

6. Signs
Occasionally, a sign is listed.  Sign "W" I assumed would be for whistle?
There are spots listed for Property Sign.  What would that sign be for?
What would a Section Post be?

Thanks!

[Todd Hackett]

"1803+04(small o raised up here) 12' X 12' Box 18'"
You're probably correct about it being a box culvert. The 1803+04 is the station number, which is the distance from a reference point along the centerline of the track in hundreds of feet plus feet, so this is 180,304 feet (or a bit over 34 miles) from station 0+00. If there's a raised underlined numeral after it, that's probably tenths of a foot, so 180,304.0 feet from station 0+00.

"What does P.T. and P.C. mean?-related to curves-PT is at the beginning of the curve and PC at the end"
P.T. is the Point of Tangency, which is the end of a curve and beginning of a tangent. The PC is Point of Curvature, which is the end of a tangent and beginning of a curve. They just mark the ends of a curve, with the beginning and end based on increasing distance from the reference (i.e. the PC should have a smaller station number than the PT). There's also a PCC, which I'm pretty sure is Point of Compound Curve, which is where the radius of curvature changes.

"A triangle shape is used in several spots too."
Can you give an example? If you're talking about the diamonds, I'm pretty sure those are mileposts.

"At a water tank (Tunnel Gulch) it says 1776+22 (small raised o) 15 W. Tank"
The "1776+22 with the raised 0 is the station number for the tank location. I'm not sure about the "15". Maybe 15,000 gallons.

"Occasionally, a sign is listed.  Sign "W" I assumed would be for whistle?"
That's what I'd assume as well.

[Jeff Young]

Box is definitely a culvert.  W Box is same as Wood Box.

Open Box is one that is right under the tracks with no top.

Lots of pictures here: http://c-sng-discussion-forum.41377.n7.nabble.com/Box-culverts-tp2262.html

[Dave Eggleston]

"The "1776+22 with the raised 0 is the station number for the tank location."

Yes, and the raised number refers to a tenth of a foot. So read that as station 1776 + 22.0' when looking at these maps, which is shorthand for 177622.0' (not 1798.0'!) from station 0 (Buena Vista in 1918). Every 1000 feet the count restarts, so everything between 177600.0 and 177700.00 is 1776+xx.x, where xx.x is the distance in feet and tenths of a foot from 1776+00.0.

The 15 is the tank diameter [edit: I originally incorrectly stated "radius"].  It says "15' W. Tank" which in this case means 15' diameter [edit] water tank. A whistle sign would be called out on its own, follow along the line and you'll likely find one.

The triangle is "delta" or the change in the line from one tangent to the next. It refers to the degrees and minutes the curve runs through on a circle. So delta 90 would be 90 degrees of arc of a full circle. Woodstock curve shows delta 228 which is 228 degrees of arc!

I just noted a really interesting detail on this particular division's maps that can also cause confusion. The mileage increases from 0 to 32 westbound from BV to the tunnel apex at 1565+60, then at the apex of the tunnel the westbound footage is reset to 1566+00 AND the mileage posts DECREASE heading to Gunnison (0) even though the surveyor's footage increases westbound! So if you only look at the ICC map's MP for Tunnel Gulch, you'd think the tank is 24.25 miles from BV becuase it's between MP 24 and 25. But you'd be wrong. In fact you're about 4.75 miles west of the apex, putting you about MP 36 if you measured from BV!

Also, these mileages will vary based on relocations of the line between 1881 and 1918 so not all timetable mileages will map exactly to the ICC map.

Confused yet?

[Kurt Maechner]

Thanks!  All this makes a lot of sense. The mileages are confusing, but at least I know what the numbers mean!

[Dave Eggleston]

I made one correction on my answer above: I called the 15' "radius" instead of "diameter." Sorry about that.

The other thing I note is if there is a sign, like "Whistle," it's denoted by a little upside-down T shaped object with the actual wording in quotes next to it.