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The Texas-California Arc of Primary Triangulation


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I originally reported on my quest to recover the Arizona stations used for this survey in the "Good Day" thread, but thought I would pull that post over and start a new dedicated thread and invite others to contribute reports on their finds of these stations as well. I know that kayakbird has recovered CF0328 CHIRICAHUA, AZcachemeister has recovered supplemental point CF0355 MULE, and I believe that Klemmer may have recoveries on a few of the stations in California.


The eastern half of the arc across Arizona from Deming Base to White Tank-Maricopa is shown in this map from the Special Publication:



And here is the western half, from White Tank-Maricopa to San Jacinto-Cuyamaca:



On these maps the principal stations are connected by the heavier lines, while the lighter lines indicate observations to supplemental points. The points marked by circles with dashed lines were not occupied, but were observed as intersection stations. The publication also includes detail maps for the Yuma and Nogales areas, where the arc was tied in to points from previous surveys of the international boundary.

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My previous report on BALDY 2:


I was out to visit the former location of CG1052 BALDY on the summit of Mount Wrightson, which recently became of interest to me as a recent find of DA1442 TABLE led me to discover USC&GS Special Publication 11, The Texas-California Arc of Primary Triangulation (33.9 MB PDF). The segment of the arc crossing Arizona was completed in the third season of of the survey (1910-1911), crossing from a baseline near Deming, NM to one between stations SAN JACINTO and CUYAMACA (Reset) in Southern California. The survey also tied in to international boundary points near Nogales and Yuma, and to additional points in California near Needles. Thirteen principal stations in Arizona were occupied to survey the arc and I've now challenged myself to visit all of their positions.


I got a bit of a late start to the day, but I got down to the trailhead and onto the trail by 10:30 for the five mile hike to the summit. Along the last bit of the drive in up Madera Canyon, the mountain looks pretty imposing




but as it turns out the trail I took (Old Baldy) is well maintained and made the elevation gain of 4000 feet at a pretty even rate. In order to make up for the late start and allow some time for searching at the summit, I pushed myself up a little harder than I should have, but I made the summit in good time and began to search. Sometime after it was occupied in 1910, a Fire Lookout Tower was built on the site, destroying BALDY in the process. In 1935, a new station BALDY 2 was monumented 75 feet southwest of BALDY. A virtual geocache has been placed requiring a photo of "the NGS disk," the disk required being a reference mark disk stamped BALDY NO 1 1935. Coordinates for the cache are for that spot, but the disk has since been pried from its setting. Some subsequent photos on the cache page show a different reference mark disk stamped BALDY NO 2 1935, which was a bit puzzling because only one RM is listed on the data sheet.


I arrived first at the drill hole spot, and with the cache coordinates loaded in my GPSr spotted it quickly. Switching to the coordinates of the station mark, it appeared to be correctly the location of BALDY 2 RM 1, so I got out my tape and compass and measured out to a nondescript spot on the ground (marked by the tape case):




Not having come prepared to dig, and not trusting a measurement from one reference mark only to want to dig, I decided to move on to my other search. While BALDY had been destroyed, its reference mark was a chiseled cross and I was hoping I'd be able to find it. I wandered past the lookout tower foundation (where I'm sure I was getting some strange looks from the dozen or so hikers lunching there watching me pace and tape) to the northeast end of the summit. I had done a FORWARD calc of the reference mark's position, and when I reached it I looked around a bit and spotted some letters chiseled on a rock, RP. My first thought was that it was a hiker's initials (which is not uncommon around here), but the letters were deeper than usual for that, and then I noticed what looked like a faint arrow above the letters. My next thought was that it was an azimuth arrow pointing to CZ1814 RINCON PEAK, which had been sighted as an intersection station from BALDY, but that didn't quite make sense, and after checking my compass, the azimuth of the arrow wasn't anywhere close to correct for that. A third look above the top of the arrow revealed the cross.




It wasn't until I dusted the RP lettering for a better photo that I spotted the clincher. Below the RP dusting revealed a chiseled USGS as well!




I started back to pick up my pack and head down, but before I got there I happened to spot the BALDY 2 RM 2 disk:




Another look at the datasheet makes it look to me that the BALDY 2 station disk and reference marks were erroneously stamped BALDY, hence the 1957 USGS recovery report noting that "ATTENTION CALLED TO POINT OUT THAT STAMPING DOES NOT AGREE WITH DESIGNATION, ESPECIALLY SINCE THERE WAS AN OLDER USGS STATION BALDY ON THIS SAME TOP. REFERENCE MARKS IN GOOD CONDITION."


Finding the chiseled cross was enough goodness for one day, but now with two good points (and maybe some help from the arrow on the remaining RM disk) a return for a more serious search for BALDY 2 will now have to be made.

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The recovery that got me started on this project was a hike with MTime up Table Top Mountain for several geocaches and DA1442 TABLE.


Table Top is located on land managed by the BLM as part of the Sonoran Desert National Monument. A long drive south from I-8 on a road that goes from well maintained graded gravel to so-so to rough jeep track brings one to a trailhead and campsite. The hike itself gains a little over 2000' over about 4.5 miles to the station's elevation of roughly 4375'.


Upon reaching the summit, we quickly found the station amidst the remains of a cairn that had at one time been built over top of it:




A closeup of the flat 1910 era disk:




We then set out to search for the reference marks, of which TABLE has three, each set at different times.


The original reference mark is a chiseled cross which was designated as RM E which was immediately obvious when I turned in that direction:




The second reference mark was added during a 1936 resurvey and is designated as RM NNW:




The third reference mark was added in 1960 and occupied as an eccentric station in order to observe some two new stations to the north along then highway 84 (now Interstate 8) that were too close to be observed over the edge of the mountain from the original station. This one took a bit more effort to find since the datasheet doesn't give an azimuth in degrees, only a distance and heading, but it was set in a prominent boulder and caught our eyes once we got in its general vicinity.




It was great to be able to recover all the marks on this one!

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Hey Southpawaz:

Thanks for starting this thread! Hope to be able to contribute to it some.


For starters, San Jacinto - 1989 - 1923 (DX5119) is well documented on the geocaching benchmarks page including all four existing marks (Azimuth mark first recovery - by Rumpled - since set in 1954). My NGS recovery log from 2003 needs an update for my recovery of the Azimuth mark this last July. Will do ASAP. At over 10,000 feet and a serious all day trek, all those recoveries were a multi-year task for me.


I would still like to spend more time on the peak some day, trying to recover all the old drill holes (if they still exist). There are also various bolts and holes that were possibly used to mount or guy various non-survey related signs, poles, etc (see Rumpled and Vader GC logs). I have a feeling that unfortunately some of the old (1898?) drill-hole RM's have been used for other purposes over the years. I'll be needing a very light tape measure, or a Sherpa. The peak is anything but flat, with rock scrambling needed to get anywhere. Sure is fun, though!

Edited by Klemmer & TeddyBearMama
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After downloading and reviewing the Special Publication, I discovered that I had already visited two of the other points used to survey the arc. The first of these was DU2086 SUPERSTITION, located on the southeast summit of the main ridge of the Superstition Mountains east of Apache Junction in the Superstition Wilderness area of Tonto National Forest. Lured by the placement of an earthcache on the peak, commonly referred to as Peak 5057, I hiked this one with MTime as well. Accessible from several different directions and located along a popular informal trail that runs the length of the ridge, SUPERSTITION had accumulated quite a few logs on geocaching.com even prior to the placement of the earthcache. We chose a route that took us up the south side of the mountain after passing through Hieroglyphic Canyon, which contains an impressive petroglyph site:




SUPERSTITION was already in place at the time of the arc survey, having been monumented in 1899 by the USGS with an unstamped aluminum disk which probably looked like this one (DU2276 GRAYBACK, set by the USGS in 1900):




Photos in prior logs showed that the station had been reset by the USGS, and indeed the station disk is no longer aluminum:




The 1965 USGS reset apparently was never reported to the CG&S, as the last recovery report on the datasheet was dated 1946.


We were able to locate all three reference marks including the original chiseled cross:




Similarly to TABLE, second and then third reference marks were added by the CG&S in 1936 and 1946. We pulled tape from the station to the three reference marks and the distances each checked to within a centimeter. After consulting with Deb Brown on how to report this, she advised me to file a recovery report of my findings under the original PID, since they do not have a PID for the reset station.


Here's the view northwest towards the lower of the two summits, just a bit lower at 5024'.



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OK, Southpawas:


Since you say "Texas to California arc of Primary Triangulation", lets take it a bit further into California!

The Primary Triangulation map below picks up where Southpawas left off, and covers Southern California. It took some serious searching on the NOAA / NGS website, and it turns out there is not an NGS Special Publication for the area, but rather it is covered in Appendix 9 of the USC&GS 1904 annual report from here:

USC&GS 1904 Annual Report

It is 65MB of download, but Appendix 9 runs only 16MB. I have Appendix 9 separately, and will be happy to email it, if anyone is intersted and can handle the 16MB email attachment. The document also covers the offshore Channel Islands (San Clemente, Catalina, etc.) very well, and goes as far north as San Fransisco (Mt. Diablo) to tie in to the first Tanscontinental Primary Triangulation Arc. There is lots more detail, many more stations in the report.


I know I have found and documented several of the pre-1904 marks (some much older!), including the key San Juan and Santiago peaks, and I'll add them in here as I have time. I'm planning to go after all the ones I can out here. Come on, SoCal folks, lets get these old Triangulation Stations! What cool history.



P.S. Thanks NOAA folks for scanning & making these available.

P.P.S. Sorry for the size, but any smaller and it isn't readable.

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I was looking at Benedict, to see if I might be able to check on that one. Searching the NGS database by name, I find Benedict and Benedict Reset. The datasheet for Benedict CG1229 comes up Fatal Error, code D (no descriptive text) but the Reset CG1033 sheet says





Is this the one they used ? Or are there possibly two station disks in the area ?


It looks like it might actually be accessible. ;)


(sorry for the caps, I just did a cut and paste from the datasheet)

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Yes, CG1033 BENEDICT RESET would be a replacement in the same location as the original BENEDICT. I hadn't looked at that one, it looks like a drive station now if there isn't a gate on the road. Hope it's still there with the radio towers (?) that have been built on the summit. Google maps view.


BENEDICT and CG1106 NOGALES 7 were the key points used to tie into the international boundary survey.



I was looking at Benedict, to see if I might be able to check on that one. Searching the NGS database by name, I find Benedict and Benedict Reset. The datasheet for Benedict CG1229 comes up Fatal Error, code D (no descriptive text) but the Reset CG1033 sheet says





Is this the one they used ? Or are there possibly two station disks in the area ?


It looks like it might actually be accessible. ;)


(sorry for the caps, I just did a cut and paste from the datasheet)

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Does the arc go east of Texas? Say into Arkansas or Louisiana?


Hi Ashallond,


This arc connected up with a previous survey of the 98th Meridian, which runs roughly through the middle of Texas. The eastern end started with a baseline between CT0993 KYLE RESET and CT0997 MCCLENNY RESET.


Here's a map I pulled out of Special Publication 54 which shows the status of primary triangulation as of 1919:


Edited by southpawaz
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Meh. Arkansas is in that nice blank spot. I've been really interested in all of the threads of the priary arcs, and would like to go after a BM or two in them, but none of them are near me at all.


oh well, thanks for the map. I hadn't seen that before, it looks really neat.

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Hi Ashallond:

It looks to me like that southern arc eventually goes across southern Louisiana. That was inherent in one of the purposes of the arcs, namely to complete a "loop" back to the starting point, as a means of checking the work. Hard to say when that might have happened. Here are the two National Geodetic Survey (NGS) - previously Coast & Geodetic Survey (C&GS) resources that some of use use to research these older (and very interesting) projects:

C&GS Annual Reports (1837 - 1965)

C&GS Special Publications (1898 - 1969)


There are some indexes & bibliographies on those pages that are searchable (on-line or in Acrobat) that make finding things a little easier. At a quick glance, I did see a number of surveys in Louisiana, but didn't see the completion of the arc. I didn't check Arkansas.


Good luck!


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The other principal point I had visited prior to my recovery on TABLE was DV1907 HARQUAHALLA RESET. The station is located at the summit of Harquahala Mountain, which at 5684' is the high point of La Paz County. According to Wikipedia, it takes its name from a Native American phrase meaning "water there is high up."


The mountain is on federal land administered by the BLM, which maintains a rugged jeep track to the summit as a "Back Country Byway." Portions of the surrounding area are designated as Wilderness, and in addition to the jeep track (which approaches from the south) the mountain can be hiked through the Wilderness from the north. On the summit are the well maintained remains of a Smithsonian Observatory which was in operation from 1920 through 1925 and is now on the National Register of Historic Places, as well as a solar powered microwave tower.


The map shows that HARQUAHALLA was used to observe 7 different principal stations and the observations were performed on 3 different days over the course of a week in December 1910 (must have been a pretty cold week for the party!). It sort of marks the spot where the arc split to head both northwest to Needles and southwest to Yuma.


I was fortunate to get a ride up to this one, as our party was at the time working on project to recover boundary monuments along the west border of Maricopa County, which runs north-south about a mile east of the summit. Prominent ridges run northeast and southeast from the summit, with a monument on each. On our hike out the southeast ridge we could see why the mountain received its name, as down in the valley between the two ridges we could see the remains of a livestock operation, including water tanks and the remains of some stone cabins.


After reaching DV2275 COUNTY LINE MONUMENT 44 we headed back to the summit. Here's a bonus photo of the county line cap (the boundary was surveyed long prior to the formation of La Paz County in 1983):




While my coworkers took a break, I detoured up to the summit and quickly spotted the station mark as well as two of the reference marks. Unfortunately, I only had time to quickly take closeup photos of the marks I found. The station was reset in 1984/1985 by the Arizona DOT with an NGS disk, probably to serve as control for a triangulation arc they did along US Highway 60 in that timeframe.




Similar to other stations in the arc, the original reference mark was a chiseled cross, which I did not have time to search for. One reference mark was added (again like the others) in 1936:




And another was added in 1948:




Another reference mark called HARQUAHALLA A POINT is shown on the data sheet but again I didn't have time to search for everything. This one is listed with a valid PID but nothing comes up for it so it may have been marked destroyed. Unfortunately, the datasheet for the original station is no longer available, so for the azimuth mark the only clue is the azimuth on the reset's datasheet.


I'm currently working on another project in the area and each time we head out that way I look up and wonder about that chiseled cross, so I'll probably be headed out there soon to look for it (though I'll have to hike it this time) and take some more photos.

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Here are the two National Geodetic Survey (NGS) - previously Coast & Geodetic Survey (C&GS) resources that some of use use to research these older (and very interesting) projects:

C&GS Annual Reports (1837 - 1965)

C&GS Special Publications (1898 - 1969)


There are some indexes & bibliographies on those pages that are searchable (on-line or in Acrobat) that make finding things a little easier. At a quick glance, I did see a number of surveys in Louisiana, but didn't see the completion of the arc. I didn't check Arkansas.



Special publication 187 is the document for Arkansas. There was a series of publications from 1885 to 1925 that documented the triangulation on the U.S. Standard datum, but the series of publications was never completed for all states, and Arkansas was not included. Then another series stated in 1930 through 1941 on the NAD27 datum, but again didn't cover all the states, but it at least included Arkansas.

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Bringing a copy of kayakbird's post on his find of CF0328 CHIRICAHUA over from the First Find thread.


Thanks for digging up your notes and taking pictures of them to share with us! I've never rubbed a mark, pretty cool and a good thing to remember when the camera batteries are dead.


I'm looking forward to getting that one, just a bit too cold down there for me for a few more months.


Hi All,


My first attempt at finding a station as an official Benchmarker turned into mostly exercise and education. I was working as a volunteer at the Southwestern Research Station in the Chiricahua Mountains near Portal, AZ when I joined Geocache in Sept 08. The manager there told me that there was a a brass cap at a near by lookout. I had had a bit of experience with the DATASHEET in a previous existence - even recovered a few, most of which I have since re-visited - so I called up Cochise Co, AZ and scrolled around until I found some marks that were close to the L/L that I had for the SWRS.


Note - the property there is a Homestead Entry Survey(HES) with several etched rock corners that really need to be Waymarked.


At that time my GPSr was strictly a passive device for my birding hobby and I didn't bother to enter the coordinates for CHIRICAHUA or FLY PEAK LOOKOUT HOUSE - didn't have a upload/download cable at that time, and the main reason for the drive to the Rustler Park trail head was to get a second, positive, observation of the Mexican Chickadee and have a nice hike on my weekly day off from dish washing.


I had learned how to enter a PID in 'FIND A BENCHMARK' but had not seen the 'Nearest:' button. Noticed that there had been a no photo log of the station in 2006 (didn't know yet to be very suspicious of exotic finds sans photo!) so figured that with the L/O tower and all the reference marks that it would be a walk in the park. Gathered up my tools - DS, Pearce Ferry Rapid field book, carpenter pencil, hiking staff

cut to my pace length with foot & 1/2 foot marks and GPSr.


Arrived at Flys Peak after an easy three mile hike w/chickadees, but no L/O tower to aim for. Legs pads were there so I stated looking 'EXACTLY 158 FEET SOUTH-SOUTHWEST OF THE CENTER OF THE TOWER' which kind of puts you off the ridge (didn't know about the good stuff in the box scores). Did find the peak bagger's log after finally turning on the GPSr and working north along the ridge trying to make its display (DDD.ddddd) match the DS but could not see any prominent rocks that looked like a good point to set a station, and none that had a drill hole. Found a large (30 inch DBH) conifer with a total of five 3/4 in iron pins driven into it. These protrude several inches and two have square nuts riveted on. There is a lightning blaze on this tree, but it didn't seem right for the calls:







Finally stumbled upon RM 2 on a 30 X 18 inch rock protruding 0.30 ft (arrow was later determined to be


pointing about 30 degrees left) and whacked a waypoint (which has since been deleted and I did not write down - an occasional error yet) and took a rub before heading down the mountain in front of the afternoon thunderstorm.


It was three weeks before I mounted another expedition, during which time I had bagged the NONPID brass in the front step of the locally known and mapped Barfoot Lookout. Still didn't know 'Nearest:' so didn't realize that I was at a PID'd spire - CF0324 BUENA VISTA LOOKOUT HOUSE - which does happen to be on Buena Vista Peak. Added to my tool bag for this attempt was a compass, screwdriver (digging and scewering), small flat prybar (digging, but great for ice in setting pockets - see JN0022 28 Dec 09);


and most important of all - a 100 ft tape (since graduated to 200 foot).


Approaching the Flys Peak summit, I happened to shortcut off the trail towards RM 2 at the perfect place and in three paces almost stepped on RM 1 in plain sight on its rock. My immediate thought was "this is


going to be easy". NOT!


Thirty minutes later I was still measuring from one RM or the other and checking exposed rocks that seemed close. Nothing! Started thinking that the station had been removed - there are areas that appear disturbed - it then occurred to me to pin the tape at the total distance and swing the proper arc.

First draped the tape around the wrong side of a small tree following RM 2's arrow and couldn't quite reach RM 1. Got on the other side of the tree - it is almost in line - and still nothing. Standing in what I figured had to be a five foot circle and randomly poking with my hiking staff, I decided it was about time to do

some birding back to Rustler Park - with one eye on the back trail for Mountain Lion - when I got a different thunk and there it was under 0.10 ft of loess and vegetative litter.


I cannot remember if it was set in rock or concrete and for some reason did not enter that fact in my field book - but I do have a faily nice rub.


I'm sure that southpawaz will clarify that point and submit a great photo spread after his visit.


Thanks to everyone here for all the information and encouragement to all beginners. And yes, I still get to an "easy" one sometimes without all the available information and required tools and go home empty; but what a great reason to be out wandering around.



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Here are the two National Geodetic Survey (NGS) - previously Coast & Geodetic Survey (C&GS) resources that some of use use to research these older (and very interesting) projects:

C&GS Annual Reports (1837 - 1965)

C&GS Special Publications (1898 - 1969)


There are some indexes & bibliographies on those pages that are searchable (on-line or in Acrobat) that make finding things a little easier. At a quick glance, I did see a number of surveys in Louisiana, but didn't see the completion of the arc. I didn't check Arkansas.



Special publication 187 is the document for Arkansas. There was a series of publications from 1885 to 1925 that documented the triangulation on the U.S. Standard datum, but the series of publications was never completed for all states, and Arkansas was not included. Then another series stated in 1930 through 1941 on the NAD27 datum, but again didn't cover all the states, but it at least included Arkansas.


Thanks for the help! I'll see what I can find near me. :anibad:

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Unfortunately the time was not available as hoped, so maybe we can team up for this one.


Though I'm sorry to hear you weren't able to make it, I'd enjoy teaming up with you for that one for sure.


Hope the rest of your run was fruitful!

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I was in Nogales area yesterday, with just a little extra time, so I went by to take a look at the situation at Benedict. Accessed from the highway to Patagonia via Old Patagonia Highway. It's a twisty road that goes up down and around hills with very expensive homes on them. Finally reach the base of Mt Benedict, the road to the top is Victorio. Well, my poor little 2wd Toy truck didn't like Victorio. It doesn't help that I only have older car tires on it LOL Anyway, there was a slanted curve that turned into a steep hill, hard pack with loose stuff on top, and I had no momentum going into it - I lost traction and was spinning tires, just barely moving forwards. I was afraid I was going to lose it and slide backwards ! I promised myself if I got to the top of the hill and could turn around, I would. Luckily there was a nice flat spot to turn around, so I snapped a couple of photos and got out of there.


I don't know what the building will be, but it's huge - see the heavy equipment on the left. Probably another expensive home. There are quite a few towers up on top, so they may not welcome visitors. Sorry for the blurry second pic, I was still quite a ways away so that was max zoom in a moving vehicle :P





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Thanks for the photos and recon report on BENEDICT, dixiedawn. That certainly is a large house! If there's no gate across the road or signage, it's certainly within range for me to do on foot.


You may be able to drive a lot further, the road does go all the way to the top. You can just see it in the first photo, there is a switchback just below the highest point of Mt Benedict. The road I was on continues just below the building, the light colored line across the bottom. Just off frame on the left, there was a large bush and I could see posts near it, if there is a gate that's a likely spot. I just didn't have time and wasn't sure about the road conditions. The "hill" was really short and would be nothing with a 4wd, but I was spinning tires, fishtailing, and only moving forward inches -not a situation I'd been in before so I got a little nervous . I need to get a new vehicle :grin:

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Thanks for the report on DEMING SOUTH BASE, Geo*Trailblazer 1. Glad to see another one of the flat 1910 disks intact. The survey crew was probably glad to be done with that part of the state. The Deming Base stations were the last of the survey that required the construction of observation towers, as all stations to the west are located on mountain tops. The towers at NORTH BASE and SOUTH BASE were each just over 10 meters high.

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When my friends Greasepot and Garlic were looking for a long hike to do on Christmas Day, I immediately thought of DV2196 WHITE TANK RESET. Located at the high point of the White Tank Mountains in what is now a Maricopa County Park with an extensive trail system, WHITE TANK RESET gave us the opportunity to get out for a great hike with the trails pretty much to ourselves.


The White Tank Mountains are located on what is more or less the western edge of the Phoenix metropolitan area, with what has become a mixture of housing developments amidst still actively farmed agricultural areas. The summit where the station was located is now covered with a large number of radio towers:


[Photo: Subman123]


Similarly to Harquahala Mountain, the White Tank range has a number of valleys at higher elevation, that at one time served as summer pasture for livestock. Our route took us up the Goat Camp Trail, and along the way we passed by the remains of a large stone corral which we presumed to be the location of the Goat Camp.


The original station was marked destroyed and reset in 1975 after it and the original chiseled cross reference mark were knocked out when the area was regraded. The reset station was marked destroyed in 2001, at which time the disk was sheared off but the stem remained. I was hoping to find the stem and the reference mark disks (like others in the series, additional reference marks were added on subsequent resurvey visits).


Our hike took us from the valley floor at about 1450' elevation up to the summit at 4018' in just over four miles. We paused for a break, a snack, and a geocache just below the summit, then continued up to look for the station. It turned out to be pretty much a case of "nothing to see here, move along." Since 2001, a new utility building for the radio tower complex has been built at the former location of the station. I quickly located RM 2:



But that was all we were able to find, as a quick pull of the tape confirmed that the station was located about 3 feet inside the wall of the new building, right about where Greasepot's shadow hits the wall:



The bearing and distance to RM 1 indicate that it was likely inside the building's footprint as well. With a long hike to return, I declined at the time to look for the azimuth mark, which is located approximately .2 miles south of the station on an undeveloped sub-peak, though my guess is that it's still there.


As a bonus, shortly after starting our descent off the peak a bobcat dashed across the trail ahead of us, the first time any of us had seen one in the wild. He was gone before we could get a photo.

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If you all get a firm date, let me know and I'll see if I can get up there to team up with you. Havasu gets pretty crazy around the middle of March.


Hey SouthPawAZ,


Just a quick note to bring this thread back to the top o' d heap and let you know, if my old legs and new knee hold out, KayakBird and I might make a run at Powell early next month.




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After the disappointment of finding nothing but a reference mark remaining at WHITE TANK, I teamed up with smgsmg a couple weeks later to tackle DW0905 KOFA 2. Located about 20 miles SSE of Quartzite in what is now the Kofa Wildlife Refuge, Signal Peak is a daunting piece of rock, and at elevation 4882' it's the high point of Yuma County. Here's a view of the peak and surrounding hills from the west as you drive in:




Signal Peak sits kind of in the middle of the split between the north tier of the arc that ran to Needles and the south tier that went to the San Jacinto Cuyamaca baseline. The original KOFA station was observed to and from POWELL almost directly north, HARQUAHALLA to the northeast, MOHAWK to the southeast, AMERICAN to the southwest, and BUTTE to the west of northwest. Observations were also made to a several supplemental point in the Yuma area including CASTLE DOME PEAK.


A well graded road took us in a good bit of the way towards Palm Canyon (location of perhaps the only native Palm habitat in Arizona), and then we veered off northeast on a lesser road towards the mouth of Kofa Queen Canyon at the far left side of the photo, where we parked and set off on foot due to the rough road conditions once it entered the canyon and became a wash road.


After three miles in along the wash, we reached the start of our ascent, which followed Indian Canyon back to the east. A short way in, we had our first view of the ascent:




Following a steep but well marked trail, we made our way up slowly but steadily, passing alongside Ten Ewe Mountain to the south as we made our way up. Bighorn sheep are regularly seen in the area, but we didn't see any on this trip. Eventually we reached the final ridge line and had an easier walk for the final approach to the summit.


Upon reaching the summit, the KOFA 2 station mark and two reference marks were quickly found. Similar to several other stations from this survey, the reference marks were set at different times, with one having been set in 1934 for the original station during a resurvey, and the second set along with the replacement station in 1949.


The original KOFA station had been set just a few feet away, but the outcroppings on top of of the peak were fairly brittle and full of fractures, and no sign remained of the drill hole or cement from the setting. For the same reason, I was unable to locate the original station's chiseled cross reference mark, the surface at its general location was just too broken up, as you can see in this shot from RM 2 to the station:




Here's a view of the rugged country southeast of the station and the summit register ammo can nearby:




After signing the summit register, we headed down the way we came, and as we neared our starting point we took a little side trip to search for the azimuth mark. I had estimated coordinates for it from the description using NG TOPO and found it within 50 feet of my guess. Here's the azimuth mark view to the station:




And conveniently, the azimuth mark view to my truck:



Edited by southpawaz
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Last Thursday I had the pleasure of meeting up with kayakbird and Okie'sKid to look for EU0920 POWELL. Located in Mohave County just east of Lake Havasu City on the Colorado River, Crossman Peak at elevation 5100' towers over Havasu where the lake elevation is about 480'. Here's Okie'sKid's photo of the peak and the London Bridge in town:




We set off bright and early, not sure how long our hike would be. After reaching a potential starting point, we evaluated as best we could from afar the condition of the road leading up a wash into the foothills, we decided not to risk anything with only 2WD and kayakbird and I set off on foot about 4.5 air miles from the summit, while Okie'sKid opted to perform base camp duties in the comfort of the local brew pub.


As it turned out, the road was in pretty decent shape and we could have shaved a couple miles off the hike but it was a beautiful morning for a walk. We knew there was a maintained road almost to the summit to service a group of radio towers located just off the peak, but a fork in the road gave us two choices and weren't sure which went to the summit, as the road is not mapped, apparently having been built since the USGS topos were last revised.


We ended up taking the wrong road, but realized it before it became too much trouble, and bushwhacked our way over a small ridge to get back on the right track. Eventually the road left the wash and started climbing up towards the remains of Sunrise mine, where we saw several open adits cut into the side of the hill. Eventually we reached the towers, then left the road for short walk along a dim trail up to the summit.


We found a cairn with a flagpole, and quickly spotted both of the reference marks set by the 1934 resurvey party. Unfortunately, they decided to place RM 2 over top of the original chiseled cross RM, and no sign of it remained visible. Here's the view from RM 2 to the station:




After first starting to deconstruct the cairn to look for the mark, we decided before we got too far that maybe we should measure, so we got out the tape and pulled the combined reference mark distance from one to the other around the flagpole. We ended up with some extra slack, which indicated that the station was not actually under the cairn. After a bit of further searching in the indicated location we spotted what looked a drill hole with just a bit of cement residue under a small acacia, which turned out to be just about where the arrow from RM 2 was pointing.


After a bit of pruning of the acacia and some cleaning, here's what we found:




A bit anticlimactic, but a drill hole's better than finding a building built over the station, right?


While we broke for a snack, I pulled out the 1910 triangulation map and we tried to spot some of the other stations that were observed from POWELL. Perhaps because this side run of the triangulation did not end on a measured baseline, quite a few secondary intersection peaks were observed from POWELL, PINE and CHEMEHUEVIS to strengthen the triangulation results.


We then turned our attention to the azimuth mark, which was set on a second resurvey in 1948. Its location was obvious as we quickly spotted the described "huge mass of outcropping white bedrock" in the indicated direction, about 1100 feet away on a east ridge. We headed down and upon reaching the indicated spot, we quickly found the mark, along with the 60 year old cairn, just as indicated in the description:




Here's the view from the azimuth mark back up to the station:




And here's a view from the vicinity of the azimuth mark looking west towards the radio towers and Lake Havasu beyond:




It was great to meet kayakbird and Okie'sKid, who was kind enough spring for lunch once we made it back to town. I really enjoyed the hunt and the company. As a bonus, between us we picked enough marks in San Bernardino County the day before and after that it should be red on holograph's maps once the logs are processed.

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I did a control survey for photogrammetry in that area in about 1978 and probably used that station. I remember the road up there, but don't remember the station specifically although I think I have some pictures taken then from the mountain.


We traversed south and the westerly along a road to some place called Black Meadow Landing as I recall. While on a high rock pinnacle turning angles an airplane came down the river and turned up out little valley, barely clearing our point, I think I could see the whites of the pilots eyes on that one.


A very spectacular environment that is for sure.


- jlw


Upon examination of the datasheet and the quad I see that I misinterpreted your photo and was imagining your mountain being on the south side of the River. Anyway that is where I was and the station was called METAL and is on the Mountain just west and a little north of Parker Dam.

Edited by jwahl
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After AZcachemeister ran short of time to attempt a recovery on DA1425 MOHAWK during his New Year's trip across El Camino del Diablo, we began making plans to team up to try for it together. Our planning intensified when, in the middle of February a new geocache was hidden on the peak by a cacher known in these parts for several hides on top of difficult to reach peaks. We were both excited to see that he included on the cache page a photo of the station, which showed to be the original 1910 disk.


Located on the Barry M. Goldwater Range east of Yuma at an elevation of 2767', MOHAWK is at the high point of the Mohawk Mountains, a range runs south from Interstate 8 with a large sand dune running in parallel to the west. Though its elevation isn't nearly as high as most of the other peaks used for this survey, MOHAWK has a prominence of over 2100':




The 1910 survey party observed 5 other stations from MOHAWK, from AMERICAN across the California border clockwise around to KOFA, HARQUAHALLA, WHITE TANK and MARICOPA.


While portions of the Range are still in use by the military, it is also open for public recreational use by permit. Permits in hand, we set off before dawn with 'cachemeister's wife AZgeckogirl at the wheel of their Cherokee. The route described in the "to reach" (approaching from the east) is no longer easily accessible due to use restrictions, and the two most recent "official" recoveries were "reached by helicopter" by the USGS in 1964 and the AZHD in 1972 which didn't give us any useful information, so we approached from the west along the roads approved for recreational use. As we drove in we began evaluating different routes that had looked feasible on the topo map. As advertised, none looked easy, and we eventually parked the Jeep alongside the road and the three of us started across the two miles of flat between us and the south base of the mountain.


As we approached, we saw a ridge that looked like it would get us to the top, 'cachemeister and I bid farewell to his wife and started up. As we climbed we started seeing quite a few Elephant Trees (Bursera microphylla), which are relatively uncommon but on this mountain they were plentiful:




As we got closer to the summit, we started encountering quite a bit of Teddy Bear Cholla, which slowed us down for frequent stops to remove their joints from our pants, shoes, and in one case, hand. Once we got within view of the summit, we could see some kind of modern equipment, which appeared when we got there to be a radio relay station of some sort, probably for Border Patrol communications. The last 150 feet involved a bit of tricky hands on climbing, but we made it and quickly found the geocache just a bit off the summit.


After taking care of that bit of business, we turned our attention to the main event, and quickly located the station in a small cairn under a rusty tin containing a summit register:




Closer inspection revealed the original 1910 flat disk:




I'm not quite sure why the 1934 resurvey party would have added that year to the disk, as they didn't do so on either of the other original 1910 disks that have been found thus far (CF0328 CHIRICAHUA and DA1442 TABLE). The recovery note makes no mention of a reset, but perhaps it wasn't standard procedure to note them at the time.


We then quickly found both of the 1934 reference marks. here's a view from RM 1 towards the station, which also shows the (solar powered) radio equipment and also some of the nasty cholla.




Finally, we turned our attention to and found the original chiseled cross RM. All station marks present and accounted for!




After finding everything and taking all our pictures, we rested a bit and snacked while enjoying the views and trying to spot some of the far off stations. Here's a view to the west with the Mohawk Dunes visible:




We headed back down and eventually reached the Jeep, having spent about 6 hours to go 6 miles. We decided to finish off the day by driving around the south end of the dunes and head back north along a different road which had a 1962 level line along it. With AZgeckogirl still at the wheel and the two of us hopping in and out every mile, we managed to pick up about 20 marks along the line on the way out, along the way catching a pretty sunset:




On way out, I passed the milestone of 1000 marks logged found on gc.com, and I couldn't have done it in better company. Thanks to both of you, it was a great day and I'm looking forward to our next excursion!



Edited by southpawaz
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Great photos of marks and scenery!!


I especially enjoyed seeing the 1910 flat, triangulation station disks. That type of disk only started being used in c1909.


I did an Inertial Survey System (ISS) test in the Yuma area in 1981. The then NGS Arizona State Advisor (LW) and I recovered 99 stations. Check out our 1981 recoveries along U.S. 95 north of Yuma and north to Quarzite and also east along the east-west road just north of I-8 (GEL is me.). Our goal was to set up North-South and East-West test courses for the ISS (since the rotation of the earth was likely to effect the ISS). We then had a helicopter fly the ISS along the test courses and land periodically on top of the known control. The ISS worked well but was soon replaced by GPS. Over the years, LW recovered many of the old marks in AZ and I remember him telling how he found an Indian necklace on a ledge while climbing up to one of the stations.




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Thanks for sharing that history, George. I see you did some tough climbs for a few of them yourself, including DB1267 GILA, which was one of the supplementary points set and used in 1911 for the survey of this arc. There's a geocache at its location now as well, but none of the cachers who've logged the station as found have posted a photo of the station disk yet.


Last year I recovered several of the marks along old US 80 which you used for this project. I'm guessing you weren't able to have the helicopter land on DB0150 WELT. :anicute:



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