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Your BM is in another.......bridge?


cesariojpn

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So, i'm looking for this marker: TU0911

 

Now, according to the datasheet, it has to be on this bridge when you adjust for the discrepancy of the coordinates, which actually points to a house overlooking the gulch: bridge in question.

 

I looked abit back, and the closest thing I found was this "cross" on one of the abutments which corresponds to the directions of the datasheet, but is not a disc: Bridge abutment with cross

 

I decided not to log it at Waymarking until I was 100% sure of the facts.

 

Today I was at the local community college and took a gander at the library's topographical maps case. Now, as I was looking, I noticed the topo maps lists a BM (BM 2125), but.....it's at THIS bridge: the other bridge

 

So wait, am I looking at the wrong bridge, or am I reading the stuff wrong?

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If you are indeed at the bridge over Kalialinui Gulch, you might want to try and look at the place where the arrow points in the attached pic.(maybe under the white rock or piece of concrete)

 

My experience with marks that are set in abutments, is it usually means a pier or crossmember of the bridge that the road sets on.(however the definition of abutment is just where two structures meet)

 

Looking at the actual compass on google earth, the directions don't really line up with the datasheet descriptions, but that would be the closest thing.

 

18bdbb72-bab8-4971-b4c8-0f9f95769225.jpg?rnd=0.2241434

Edited by LSUFan
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The data sheet does say that it's on Highway 37, whick looks like the second bridge. And the elevation listed on the datasheet is 2125'. So, that's where I would be looking. Is that bridge old enough? Scaled coordinates are not usually too bad, but I've found one that was 1025' off. And sometimes typos occur.

There are excellent topo maps online (I like Acme Mapper.)

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The data sheet does say that it's on Highway 37, whick looks like the second bridge. And the elevation listed on the datasheet is 2125'. So, that's where I would be looking. Is that bridge old enough? Scaled coordinates are not usually too bad, but I've found one that was 1025' off. And sometimes typos occur.

There are excellent topo maps online (I like Acme Mapper.)

 

I agree with Harry, as I now see the first bridge you referenced isn't on the right road (Hwy 37). The second bridge, besides being on the right road, also has the correct compass directions.

 

Good call Harry Dolphin. If we paid you anything, you'd deserve a raise. LOL

Edited by LSUFan
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I haven't studied this case, so my comment may not be applicable. But keep in mind that the scaled coordinates were taken from the 1960's maps and highway numbers have sometimes changed.

 

I know of a local mark that was set on "Hwy 30" in the 1930's, the coordinates taken from "Hwy 30" most of a mile south in the 1960's, and the present "Hwy 30" is over a mile further south of that.

Edited by Bill93
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Harry got it right. Looks like somebody goofed in scaling the coordinates. Besides the Highway number, (which as Bill93 points out is subject to change over time), the datasheet elevation matches the BM depicted on the topo. The first bridge, on Lower Kula Road, is about 100 feet higher.

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Thanks Guys. I thought something was amiss. Now to approach the place safely.....gonna have to pull out the Hi-Viz vest out again.

 

edited to add: I just realized that if this BM coordinates is ridiculously wrong.....the whole series might have a few more bizarre anomalies that i've suspected....

Edited by cesariojpn
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As mentioned above it is best to use scaled coordinates with caution. Use the directions in the data sheet.

 

Using Google Earth I measured off 3.2 miles from the driveway of Kula Elementary School along highway 37 and arrived at 20° 48.341'N 156° 19.651'W. That puts me at the south end of the second bridge in your post.

 

Using street view I could not see any evidence of a benchmark. But it is most likely still there. Look below the steel guard rail. It was likely installed after the benchmark was put in. If it is not there then look on the far side of the concrete wall and down. It could be on the wing wall like TU0509.

 

55d982d0-08f7-495c-b7ff-40f94d4ed6b5.jpg

Edited by 68-eldo
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As mentioned above it is best to use scaled coordinates with caution. Use the directions in the data sheet.

 

Even the directions for this series of markers is abit wonky with some of them. This for example: TU0903

 

Um, semi-circular lawn area with a concrete slab? Ehhhhhh?

 

And: TU0899

 

Bridge A or Bridge B? School search is abit confusing given there is one that is gone, one public, and one private in the general vicinity of the area. None have said name on datasheets.

 

I'm finding better luck with the 24 series than the 23 series!! Not trying to get you guys to do the work for me, but ARGH!!, so frustrating with this series.....

 

I'm even shuddering trying to attempt to find the marks supposedly on Oprah Winfrey's property!!

Edited by cesariojpn
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As mentioned above it is best to use scaled coordinates with caution. Use the directions in the data sheet.

 

Even the directions for this series of markers is abit wonky with some of them. This for example: TU0903

 

Um, semi-circular lawn area with a concrete slab? Ehhhhhh?

 

And, here is where you need to do research, and not rely entirely on the coords listed. The University of Hawaii Observatory at Waiakoa is located (at the present time) Ohia Ku off of Kula Hwy (Rt 37). It did not take a lot of Googling to find this out.

19659ab3-0287-4608-a3b3-040159deca65.jpg

If this is the actualy location, the coords are very bad. About 5 miles off. Perhaps a couple of transcription errors? N 20 49 instead of 20 45? It does happen. I have no idea if this is the right place.

Your problem is expecting the the coords on a scaled mark to bring you to the exact location. The decriptions may seem wonky to you, but the meant something to the surveyor who put the mark out. These are only 30 years old. Try following a dirt road to a 24" maple tree as of 1934! Times change, and so does the landscape. Trees die, schools get torn down, bridges are replaced, roads get moved.

Good luck. But don't set your expectations so high, and do a lot more research.

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As mentioned above it is best to use scaled coordinates with caution. Use the directions in the data sheet.

 

Even the directions for this series of markers is abit wonky with some of them. This for example: TU0903

 

Um, semi-circular lawn area with a concrete slab? Ehhhhhh?

 

And, here is where you need to do research, and not rely entirely on the coords listed. The University of Hawaii Observatory at Waiakoa is located (at the present time) Ohia Ku off of Kula Hwy (Rt 37). It did not take a lot of Googling to find this out.

19659ab3-0287-4608-a3b3-040159deca65.jpg

If this is the actualy location, the coords are very bad. About 5 miles off. Perhaps a couple of transcription errors? N 20 49 instead of 20 45? It does happen. I have no idea if this is the right place.

 

Um, you did notice this sign if you swung left in the streetview link, right?

 

kqAeN.jpg

 

Plus, that area you have didn't exist till about a half-decade or so ago. Oddly enough, there is supposedly an unlisted BM according to the topo maps nearby about a good stones throw NW from TU0912 near that greenspace above "Email" in the infobox.

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I think this time Harry is steering you wrong. In the streetview you showed us, it was hard to make sense of the description - try this one:

 

6040cc9a-93c4-4f40-9285-bf4816a25d7a.png?rnd=0.4519879

 

The semicircular lawn area could be the space between the two driveways, although by the location of the utility pole, the paved portion may have been expanded since 1979 to cover the concrete slab. Try looking 11 feet east of the pole, which seems to be consistent with the rest of the description, ie. 42 FEET EAST OF THE CENTER OF THE ROAD, 35 FEET NORTH OF THE SOUTH ENTRANCE ROAD, 100 FEET SOUTHWEST OF THE SOUTHWEST CORNER OF THE LABORATORY, AND 11 FEET EAST OF UTILITY POLE NUMBER 1.

BTW, this location is also consistent with the BM elevation, unlike Harry's suggestion. It seems to be very close to the scaled coords for TU0902, S23, which should be found near Hwy 37, almost 80 feet lower. Another case of poorly scaled coords.

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Um, you did notice this sign if you swung left in the streetview link, right?

 

kqAeN.jpg

 

Plus, that area you have didn't exist till about a half-decade or so ago. Oddly enough, there is supposedly an unlisted BM according to the topo maps nearby about a good stones throw NW from TU0912 near that greenspace above "Email" in the infobox.

 

Oh, well. Sorry about that. I'll go sit in the corner.

No. I didn't see that sign. So, as Holtie22 said, it looks like the right area/right elevation. But a lot of changes can happen in forty years. The driveway might have been enlarged. The mark may have been paved over/dug up. It does happen a lot. But the description meant something to the surveyor who put of the mark in 1979.

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And: TU0899

 

Bridge A or Bridge B? School search is abit confusing given there is one that is gone, one public, and one private in the general vicinity of the area. None have said name on datasheets.

 

Reviving this discussion, I'm with Harry again and also vote for Bridge B. The scaled coordinates seem to be reasonably accurate this time, as they put you on Highway 37 near a feature labeled Waiohuli Gulch on the topo, and also near a plotted BM. Unfortunately, the topo may have a typo as the printed elevation of 3225 does not match the contours at the plotted "X". These indicate an elevation consistent with the 2955 found on the datasheet, leading me to believe that this is P 23, TU0899. Let us know if you go look!

BTW, try these coords - from Google Earth: N20 43.213, W156 20.714

Edited by Holtie22
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Election Year!! Road Construction galore!! (Three actually on my route to the Thrift Shop; repaving, installing curbing, and utility works. Four if you count another repaving project on a street that skirts my travel route back home).

 

VmHCJ.jpg

 

The bridge was on part of the highway being repaved, and I doubt i'd get away with checking for the BM while having heavy equipment running about nearby.

 

Guess this will have to wait for later in the month to go back to check and recheck another culvert for a BM (TU0898). Which I thought would've been here.

 

Only got TU2869, TU0901, & TU0905. Reporting TU0904, TU0900, & TU0899 as possibly missing (evident construction improvements at those BM areas). Avoided TU0897 & TU0912 due to heavy road traffic, road construction, and unsafe conditions.

Edited by cesariojpn
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