Re: Old GP Road Alignment

I believe that some of the Old GP Road switchbacks from the point where the old side road to the Sentinel Dome parking lot branches off the GP Road were aligned differently than the current road. At least I've noticed a few signs of what might have been the old road diverging from the modern alignment in a few places, but I haven't explored it in any depth.



Edited 1 time(s). Last edit at 11/09/2015 06:40AM by chick-on.

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Rob65
I've noticed a few signs of what might have been the old road diverging from the modern alignment in a few places, but I haven't explored it in any depth.

The only stretch of the Pohono trail I'd never been on was the short stretch between GP and Sentinel Dome (more accurately, from GP to that radio facility (or whatever that service building with the big antennas is) right before you leave the Pohono proper to head up to Sentinel Dome). I took a quick run up there the last time I was in the park and noticed a spot where an unpaved road veers off the current road right where the Pohono crosses over one of those final switchbacks down to GP. I thought it might be an earlier alignment but, as I kept an eye on it while heading up the trail, that unpaved segment seemed to dead-end at some kind of storage tank. That doesn't mean it's NOT part of the original alignment but it looked like some kind of later service road when viewed from the Pohono. Not sure if that's one of the "few signs" you noticed.

I know what you're referring to, and that wasn't what I was thinking of. I seem to remember seeing some things that looked like the original alignment farther up, above or near Washburn Point, but the memory is a bit foggy since I didn't have detailed maps with me and wasn't really focusing on the Old GP Road during that trip.

I just stumbled across this old "Historical Overview" of the Glacier Point Road that has quite a bit of detail that I'd never seen before...including a reproduction of a map showing several variant alignments of the current road when it was first being proposed. This map, on page 9 of the document, is (unfortunately) pretty blurry and hard to make out but the accompanying text points out some interesting proposals, including a consideration to make it a "lollipop" route that split at BV CG with one side going "around Sentinel Dome to the north" and "the other passing down the Illilouette Canyon to the south, thus making a loop road."

There's another map that shows the comparison of the new and old alignments (including a spot where the old road is a little east of the new road, starting near the Mono Meadow TH and going for a couple of miles (I've not investigated this section so don't know how overgrown it is). This map (on page 2 of the document) does not show all the details of the deviations (the text, for example, mentions a number of re-alignments of the switchbacks that start by Sentinel Dome and also says that "The route between Bridalveil Creek and the Sentinel Dome Saddle, comprising 5.233 miles, would essentially follow the general line of the old road, intersecting it at many places." Neither the switchback reconstruction nor the "many intersections" are shown on the relatively coarse map on page 2 (other than the long stretch starting near the Mono Meadow TH mentioned above). Chick-on actually posted a much clearer comparison map a while ago but it doesn't go quite all the way out to GP so it's hard to trace the switchback realignments.

I haven't had a chance to read the document in detail yet but there's some pretty interesting stuff in it for old road junkies.

P.S. to the moderators: It probably makes sense to split this and the preceding few messages (where Rob and I start digressing about the OGPR) into a seperate thread.



Edited 2 time(s). Last edit at 11/08/2015 07:22PM by DavidK42.

I like that old historical view document.

At the bottom of page 15, it talks about a gravel quarry near Grouse Creek. As near as I can figure from the description, it would have been located pretty much on the original stage route (Old Wawona Road) where it runs across Grouse Creek west of the current road. I don't have any old maps that show a former quarry there. Google Earth doesn't give any hints, either. Maybe it was just a surface scraping, but I'd be interested in learning if any of you have a map that shows it, or have seen the foundations of the gravel crusher....

Dunno I ever posted this one...

Modern on top of 1938.



The section below Washburn is intact... mostly... kinda neat. You have seen?

Haven't explored much around Ostrander Rocks... and Mono Meadow... other than going up Ostrander Rocks from
Bridalveil campground (grrr.... the old road east of there is a mess)... and a quick poking around looking for
the Pioneer Cabin at Mono Meadow... it's on the list o things to look for...

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O... also looked a couple times now for the Old Peregoy Meadow trail... and it's just so much
duff and dirt... that I personally haven't found a thing... having looked twice... more or less...

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ok... here's another overlay of that trail... which includes Modern GP road...



on a related note... think I followed the portion of Old Tioga was missing near Fairview / Pothole dome...
need to dial that in on a map... (hint: been hiking a few days this year in the park... ) (so much I got an award)
(ok, I didn't get an award) (but was told I should) (whats the award? craziest nutjob?)
(anywho... not huge amount of time to goof with maps n such)

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Interesting: on this overlay, it looks like the old road just crosses over the new alignment after the section that leaves the BVCG and then stays north of the current road until you approach the Mono TH (where it crosses to the other side of the new road). The document I posted above makes it sound like the two roads were actually on the same alignment for much of this stretch. I know that these older maps aren't always completely accurate and so not always easy to align with later maps but any idea if there was really that much discrepancy between the two routes in this area or if that's an alignment issue?

Sorry I just don't know. Need to investigate further...

I suspect that they were aligned .... and that the old map is just too crude...

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Edited 1 time(s). Last edit at 11/09/2015 08:28PM by chick-on.

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chick-on
The section below Washburn is intact... mostly... kinda neat. You have seen?

No...haven't checked that out yet...for years, I was under the impression that there had NOT been any realignment of the switchbacks so never even looked for the old road there but now it's definitely on my list to go looking for that next time I'm out there.

Quote
chick-on
Haven't explored much around Ostrander Rocks... and Mono Meadow... other than going up Ostrander Rocks from
Bridalveil campground (grrr.... the old road east of there is a mess)

You said it! It's only about 0.9 miles from the east end of the CG back to the current GPR but for a good chunk of it, I was content to tell myself "I think I'm probably in the general vicinity of the old road! At the very end ("end" as in "where it intersects the new alignment", I pretty much gave up but, given the evidence of the old/new criss-crossings on the Wawona Rd, I expect that the crossings of the old/new GPR probably involved a certain amount of obliteration at the crossings.

Section below Washburn Pt. (please be diligent in exploring... )
switchback...

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Was able to follow that east portion... (it's trail on USGS Map) ... but... it wasn't trivial...
I know I have photos if you would like some...

Here's the track of the Old GP road (blue) ...

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Yup...I've done the whole stretch that you've got here and from Badger Pass west to Chinquapin. It's what happens east of here that I still need to explore more. In particular, I wonder about that service road that goes up to the back of Sentinel Dome. It sure feels like it's part of the old road. It gets a little confusing when you get to SD, though. If you follow the line of the service road straight ahead, you end up on a bit of a loop with some wonderful views and you end up looping back to where you started. I'm guessing that this might have been some sort of side-road feature...a bit like IP but it's a little odd that they should have built this loop so close to Washburn and Glacier Points.

Right before that "straight-ahead" bit, there's also a section that peels off to your right, going between two fairly old trees.

Again, this feels like it could be a piece of the old road (in some stretches more than others).

Eventually, it dead-ends down at the radio-tower that you go by if you're heading down to the Pohono Trail from SD. I poked around there a little bit on my last trip and it looks like the road might switchback off to the right, just before you reach the radio tower. I was short on time when I was there and saw enough to want to look more. If it is the continuation of the road, that continuation is VERY obscured...not just overgrown (it's actually not especially overgrown), but more washed away. It's much more obliterated than what I see looking at your pictures of the remnants of the switchback below Washburn. I shot a little video here but don't think I took any photos.
(In case it's not clear, the spot where the track starts at the bottom is where the gated service road peels off to the left, just before you hit the 15MPH section of GPR.

Looking at your 1938 map above, it looks like the bit that goes down to the radio hut is NOT part of the old road (I walked this stretch at about 6AM, just as the sun was coming up so I may well have convinced myself I was seeing signs of old road that weren't really that old). On the other hand, that loop to the east of SD clearly IS on your 1938 map, albeit as a secondary road so maybe that was a "nice-view" side-trip on the way out to GP.

As you say, it's not clear just how much the current alignment diverges from the old alignment between BVCG and those final switchbacks. It seems pretty clear that there's a significant section near the Mono Meadow TH that is slightly east of the current alignment (this is even called out in the text of the old proposal document I mentioned above).



Edited 4 time(s). Last edit at 11/10/2015 01:51PM by DavidK42.

I agree. The portion form BVCG to Mono Meadow... I don't think there is
much left to see there.. and imo from the Topo and all ... seems like
it would follow the same course. The section from Mono to the Taft Pt. Parking...
now that is another story.... it needs exploring...

The loop near Sentinel... I am pretty certain... that was a place to park and
go up Sentinel... and open to the general population. the road to the radio
tower/cam, etc... was put in later.. and it simply deadends... it def. was
not part of the old road... the same is true for the water tower which
dead ends much further down... you should follow it sometime too.

Winter is coming... will have more time for this sorta thing... when storms are hitting...

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I'm fairly certain that the Sentinel Dome road was a side road and not ever part of the old GP Road. I don't think it was closed off until sometime in the mid-1970s, as I am pretty sure I remember driving up to the old parking area at the base of Sentinel Dome on one of my first family camping trips to the park.

The switchback shown on Chick-On's map and photos is the one I remember seeing pieces of on a visit a few years ago.

Quote
chick-on
Modern on top of 1938.

Interesting that that's a 1938 map. The new road was completed out to GP in 1935. I know that, even nowadays, these USGS maps sometimes have a publication date of some particular year when, in fact, the actual drawing was done a number of years before. Regardless of when the map was actually drawn, it's clearly the old road and your overlay is very helpful (as always!). Thanks for posting.



Edited 1 time(s). Last edit at 11/10/2015 01:35PM by DavidK42.