Updated: Jul 24
Total Marks Recovered: 23
Named Stations: 3
New Agency: 1
GPS on Bench Marks: 2
Miles Walked: 3.6 miles
Total Elapsed Time: 5h 41m (from the first photo to the last photo)
Moving Time: 2h 4m
Today I planned for a full day of Survey MArk Scavenger Hunting working easterly on State Route (SR) 76 corridor from Pala to Pauma Valley, on a 21-mile stretch of road. Overall, I had good luck recovering marks today, locating 23 from a list of 27. My main challenge was thrashing through overgrown brush and digging through accumulated dirt to locate many marks.
The last time I was looking for survey marks on SR 76, I had a list of GPS on Bench Marks priorities that stretched westward from the junction of the 15 Freeway and SR 76 toward Oceanside, on that outing, I'd only recovered a single mark, the rest on my list were either located in active construction zones or were likely lost due to previous road widening projects.
Jump to a Specific Recovery...
DX3442: J 1312 (Fallbrook, CA)
DX5562: SD6-65 (Fallbrook, CA)
DX5563: SD6-66 (Pala, CA)
DX5564: SD6-67 (Pala, CA)
DX5565: SD6-68 (Pala, CA)
DX5567: SD6-70 (Pala, CA)
DX3896: MILK (Pala, CA)
CC4211: MILK RM 1 (Pala, CA)
CC4212: MILK RM 2 (Pala, CA)
DX1272: S 299 (Pala, CA)
DX1273: TE 238 (Pala, CA)
DX1285: TE 248 (GPSonBM) (Pala, CA)
DX3892: BENCH (Pala, CA)
DX3893: BENCH AZ MK (Pala, CA)
CC3309: BENCH RM 1 (Pala, CA)
CC3310: BENCH RM 2 (Pala, CA)
AI4546: GWM 1 (Pauma Valley, CA)
DX0515: PMT 66 (GPSonBM) (Pauma Valley, CA)
DX0505: A 300 (Pauma Valley, CA)
DX5303: SAN DIEGO GPS 34 (Pauma Valley, CA)
DX5084: CUCA (Pauma Valley, CA)
CE9927: CUCA RM 1 (Pauma Valley, CA)
CE9928: CUCA RM 2 (Pauma Valley, CA)
Hide and Seek! DX3442: J 1312
This was my first recovery of the day, a Vertical Control Mark set in a rock outcrop on the side of SR 76. The first two pictures are the end result of the recovery. If it hadn’t been for the witness sign when I walked up to this one, I may not have located it. The datasheet had listed the mark's distance from two different landmarks (the end of a turnout and a storm drain), but those measurements just put me in the general vicinity. Even with rough coordinates, "to reach" directions, and a witness sign, this one was a challenge to find!
This one took a few trips back to the car to get different tools to help with the process. I used one of my trekking poles to probe in the brush for the rock outcropping and my hiker trowel to dig out the dirt covering the mark. I didn’t think to bring my clippers on this trip, but I should have as I could have cleared the brush covering this mark. As it turned out, I also had to bushwhack to reach several marks throughout the day, despite them being not too far off the road.
The Metropolitan Water District of Southern California
I had listed MWDSC survey marks as potential recoveries on previous trips but never had any luck finding them. As noted above, many were likely lost during reconstruction and widening of SR 76 or were otherwise lost. Today, I hit the jackpot! I had six MWDSC marks on my list and I recovered five of them, the "one that got away" was located in the center of a fenced-in property behind a locked gate.
For me, a major part of the fun of recovering survey marks is digging into the backstory and history surrounding them. Perhaps the story is about the region, a particular structure, the geology, the significance of the mark in cartography or navigation, or the agency that set the mark.
Survey marks at the very basic level are used to measure and establish horizontal and vertical controls, they become known positions of latitude, longitude, and/or elevation. This information is then used in a wide range of activities, not the least of which is infrastructure-related engineering projects. All of the MWDSC discs I found today were set in 1993, so they seem to have a more modern-day utilitarian purpose than some cool historical twist. However, upon further research, I learned the District played an important role in the development of Southern California!
According to the MWDSC website:
the district was formed in 1928 for the purpose of building the great aqueduct across hundreds of miles of sun-baked desert to bring Colorado River water to the young and vibrant metropolis. Decades later, the effort still stands as an historic engineering and construction achievement.
Originally, the aqueduct supplied water to Pasadena, Beverly Hills, Burbank, Compton, Santa Monica, and Orange County. In the '40s and '50s, water agencies from Ventura, San Diego, and the Inland Empire joined Metropolitan. It continued to grow in the decades to follow and currently works with 26 member public agencies to keep the water flowing to Southern California.
Tribute to a Defunct Dairy?
Named survey marks are always my favorites, when I started my hiking challenges last year and began finding metal discs at the summit with the name of the mountain stamped on them, I thought it was the coolest thing. As my knowledge of survey marks grew, I realized that they weren't always named after mountains, and in fact, most were simply numbered with seemingly random alpha-numeric combinations.
With experience and research, it's much easier to make sense of the alpha-numeric designations stamped on each disc as they relate to a particular survey project. The named designations however are the interesting ones as they invariably have a story and some history tied to them.
DX3896: MILK 1975
As I researched and put together my list of target marks for the day, my overriding criteria was that they are located very close to the roadside, I had my new knee brace, but I was still mindful about doing a lot of extended walking. When I saw the MILK station on my map, it was about ¼-mile off the road on a low hill overlooking the valley, accessible by a dirt road that was used when they upgraded the power poles in the area. Since there appeared to be a passable road to hike on, I added it to my list. What was once a dirt road was now overgrown with tall grasses and weeds, but it was an easy ascent to the trio of power poles on the hillside. According to my map, the mark was a short scramble up the hill past the power pole, I picked the easiest path and started up quickly locating reference mark number 2. Standing on RM 2 facing the direction of the directional arrow, I spied the pile of rocks where the station disc was located, I turned about 90 degrees to my right and easily spotted RM 1 on top of a nearby boulder.
Of course, there's no way to not 100 percent for sure, but my guess is that the CALTRANS surveyors who set and named this mark did so because it overlooked the valley that was home to the Pete Verboom Dairy for almost 35 years.
Pieter Verboom emigrated from Nazi-occupied Holland in 1946, settling originally in Buena Park where he operated the Buena Park Dairy until moving to San Diego County and settling in Pala in 1966. Once in Pala, he began building a dairy farm that would ultimately cover 100 acres and included 14 buildings on the property (the dilapidated remains of many are still there). Back then, dairy farming was prevalent throughout San Diego County and I read one account that said when Verboom arrived in 1966, there were more cows in Pala than there were people!
This station was set in 1975 during a time when the dairy (and others in the valley) was likely booming. However, over the years leading up to his eventual exodus from Pala, increasing environmental regulations and changes in demand had a negative impact on the family dairy farmers in the region. By the time Verboom moved his 1,200 head of cattle to Orland (north of Sacramento) in 2000, more than 100 diaries either left San Diego County or closed completely. Coincidentally, March 2000 marked the ground-breaking for the Pala Casino Resort and Spa and was the beginning of casino development by the Native American Tribes of the region.
CALTRANS had secured an easement that went right through Verboom's milking barns, purportedly to widen and straighten the road to deal with increased traffic anticipated due to the casinos. Gregory Canyon Limited, a group that planned a landfill in the area bought his land to use mostly as a buffer around the actual landfill. The landfill was a hot-button topic for the area and never did come to pass. The land has laid untouched mainly because of the protected habitat for the least Bell's vireo, an endangered species in Southern California, and that most of the land is in the 100-year flood plain.
Just a brass disc in a rock? How about a history lesson launching pad! 😉
DX1272: S 299 1935
I like to think of these U.S. Coast & Geodetic Survey Benchmark discs as the "Ole Reliables" of the survey marks. Nothing too fancy, just an alpha-numeric designation and usually mounted in a very reliable location. This particular one was clearly visible from the road and was an easy recovery.
DX1273: TE 238 and DX1285: TE 248
2 Down, 43 To Go!
The next two survey marks that I found were standard San Diego County Engineer Department Survey Monuments, identified by the NGS Agency Code CA-073 (San Diego County). They both belong to the survey project covering the 6 miles of SR 76 from Pala Fire Station 66 to Cole Grade Road. There are a total of 45 marks that begin with the letters TE (I originally thought maybe this line started in Temecula, but that was just a guess) The first numbered mark, near the fire station, is TE 129 (DX1275) and the final mark not too far from Cole Grade Road is TE 254 (DX0522), they are all stamped as being set in 1968 or 1969.
Under normal circumstances, this one (TE 238) would have been easily visible from the road as it was mounted at the end of the culvert headwall, but when I approached, the piece of the tire was laying on top of the headwall covering the mark!
Based on the coordinates and description to reach TE 248, I honestly didn't think I'd be able to get to it. My map had the estimated location over the side of the cliff that overlooks the Wilderness Garden Park, and when I mapped the actual coordinates for the recovery, the address comes up as in the Wilderness Garden Park! Based on its location I had to park further up the road and walk back to the beginning of the cut bank in order to get to it, fortunately, it wasn't too far in from the road and there was a clear path to it. You really don't get a sense of it in the photo above, but it wasn't too far from the cliff either!
This was also the first of two GPS on Bench Marks priority recoveries that I would find today 😊
A real BENCH mark!
While I am sure that many named survey marks have a fascinating or historical backstory, I am equally confident that others are somewhat random and fairly pedestrian. I have no clue as to the origin of this mark's name and maybe the surveyor who set it didn't intend on the obvious pun, but the fact that this one is literally a "BENCH" mark had me rolling my eyes when I recovered it.
A true Benchmark is a specific type of survey mark that identifies a point of known elevation. It has also become the generic term used by people outside of the surveying world to identify ANY disc-shaped survey mark. I have recovered 15 different types of disc markers since I began this project, a few of the more common ones being Triangulation Stations, Reference Marks, and Vertical Control Marks.
A Thing About Azimuth Marks
The BENCH AZ MK was the only Azimuth Mark I recovered today and I was pretty excited to find it.
Beginning in 1927, the National Geodetic Survey added a third Reference Mark, or “long RM”, which was set about ¼ mile distant from the Triangulation Station for use in providing a starting azimuth (direction) for local surveys.
As I've mentioned in previous articles, locating the Azimuth Mark for a station is often a little trickier than finding the main station and its reference marks. One criterion for setting reference marks is that need to be within in line-of-sight (LOS) to the primary station, if something obstructs that LOS after the mark has been set (usually some man-made structure), a new RM must be set.
By their nature, Azimuth Marks are not generally in LOS and their location is only noted on the datasheet by their geodetic azimuth to the primary station (the geodetic azimuth is based on True North) The disc is aligned with the azimuth arrow pointing toward the station. You may unknowingly stumble upon an Azimuth Mark, but if you're intentionally searching for them, you'll need to brush up on your map and compass skills.
Finding the Azimuth Mark when you have the precise coordinates of the primary station is relatively straightforward, you can plot the azimuth, draw a line through your two points (I usually extend my line for one mile) then set out following the bearing. I'll generally start at a point 0.2 miles from the primary station just because I know they're never closer than that. Sometimes I'll have additional information to help narrow down the search, such as how the mark is set or nearby landmarks that will allow me to skip ahead to a specific point on the line I plotted.
If you don't have precise coordinates for the station, then locating the Azimuth becomes significantly more difficult. This happens to me a lot, I'll have "scaled" coordinates for a station from the datasheet, for simplicity consider scaled to mean "estimated". While the physical location of the mark MAY be at that exact spot, I've found marks as much as 250 feet away from the scaled coordinates! Without precise coordinates for the station, you'll just be guessing trying to find the Azimuth. This is why most of my Azimuth recoveries occur AFTER I've found the primary station and have a chance to plot the azimuth on a map.
AI4546: GWM 1
This is the third U.S. Geological Survey Bench Mark disc stamped with the designation "GWM" that I have recovered, I have no idea what the significance (if any) the GWM initials have, but I do like this particular marker because the inner ring of pre-cast text states "In Cooperation with the State".
I recently learned how to look up surveying information about all the survey marks either set or verified in a particular surveying project, while I haven't found the original project from 1947 when this mark was set, I did locate a project completed by CALTRANS in 1995. The San Diego County Peripheral Run included 154 established benchmarks and 155 Temporary Benchmarks, on a run spanning 227.4 km (141.3 miles) from the 8 Freeway to the junction of the 15 Freeway and SR 76. This mark, and many other recoveries that I have made, is included in that project. One seriously cool thing about discovering this new tool is that it gives me confirmed coordinates for ALL of those marks! Of course, the data is 26 years old and can't account for lost or destroyed marks since then, but it sure beats starting off with scaled coordinates from the NGS datasheets. 😉
DX0515: PMT 66 (GPSonBM)
This was the second mark that I recovered today that was on my GPS on Bench Mark Priority list and it definitely fell into the "Easy-Peasy" category 🤣 It's located on a boulder in a field right next to St. Francis Episcopal Church, about 50 feet from the edge of the Church parking lot.
Today's GPSonBM recoveries will also be included in my end-of-month wrap-up for July recoveries. There are a total of 110 survey marks remaining as priorities in San Diego County. I have recovered 30 of them so far. My goal is to have 100 total GPSonBM recoveries by the cutoff date at the end of the year, I will have to go outside of San Diego County if I want to reach that goal as I've already identified more than 10 survey marks that I cannot access due to private property restrictions (mostly marks near railroad tracks or inside fenced facilities on state or federal property.) 🤷🏻♂️
DX0505: A 300
While this mark did have a witness post nearby, I knew it was mounted in a boulder by the side of the road and this boulder was the only one there. I really should have added a picture from the other side of the road to add more perspective to where exactly this boulder is located because there is a very large drop-off just on the other side of it! It's on the West side of Pala Road (also known as SR 76 or County Road S6), on the East side of the road is a sheer rock outcrop, this section of road winds up the hill about a mile and a half west of the turnoff for South Grade Road, the steep, twisty ascent to Palomar Mountain favored by road cyclists and motorcycles alike.
I like finding marks like this because they are always in perfect condition, but it does make me wonder what it was like for the surveyors who originally set marks like this. How did they decide that THIS boulder on the side of a mountain would be the best place to put this mark?
Looking at the history of the road, it is very likely that this mark is associated with the official designation of the road as legislative Route 195 in 1935. As late as 1930, this was still just a dirt road East of Pala. Ultimately, during the 1964 state highway renumbering, Route 195 was legally redesignated as State Route 76.
DX5303: SAN DIEGO GPS 34
This is my 8th recovery of a marker in the "SDGPS" designation series, I may make this a project to recover as many of the marks in this series as I can. I do know that there is at least one that is also a GPSonBM Priority that is on private land and is inaccessible. Still, it would be fun to see how many I can find.
The last of my "named" stations for the day, CUCA was an interesting one because the Reference Marks weren't aligned properly to point towards the station disc! I found RM 1 first, took my pictures then followed the direction of the arrow expecting to find the station, walking out to the edge of the road without finding it. I held the line across the road just to make sure it wasn't on the other side of SR 76, nothing.
Checking the datasheet, the station was supposed to be located 35 feet NE of a telephone pole, so I went back to the pole, took my bearing, and found the mark in a standard 1-foot square concrete monument. To locate RM 2, it was just a matter of working outward from the station, looking for rock outcroppings that were about the same distance from the station as RM 1 was.
When I found RM 2 I noted that, like RM 1, it was set in the rock so the arrow pointed across the street (northerly) and NOT toward the station disc. These may be the first reference discs that I've recovered that were set incorrectly 🤔
This was a curious name for a mark, and I figured there was some meaning based on the history of the region, much like the 'Milk' station mentioned above. This part of San Diego County was home to descendants from two Indian groups: a band of the Luiseño tribe, and the Cupeño Indians (one of the smallest tribes in California).
The Pauma Band of Luiseño Mission Indians, of the Pauma and Yuima Reservation, is one of six federally recognized tribes of Luiseño Indians in San Diego County located just east of a larger tribe, the Pala Band of Luiseño Mission Indians.
According to the Valley Center Historical Society, Pauma is an Indian word meaning “I bring water” or “a place where there is water” (a reference to the San Luis Rey River which flows through the valley).
The area that is known today as Pauma Valley has been home to Indians for centuries. Early Spanish maps identify the Pauma region as an Indian rancheria. In 1795, an exploration party from the San Diego Mission, led by Fra. Juan Mariner was the first group of white men to visit the area.
In 1844, a Mexican Land Grant of three square leagues (13,310 acres) was given by Governor Manuel Micheltorena to Jose Antonio Serrano. He called it Rancho Pauma. Serrano was said to have been a splendid horseman who regularly took part in bullfights, built an adobe home, and stocked the ranch with cattle and horses. Adobe walls of the original house were 24 inches thick.
Adjoining Rancho Pauma to the east was a one-half square league parcel (2,174 acres) given by Mexican Governor Pio Pico in 1845 to Maria Juana de los Angeles, an Indian. Among the more prominent owners of the Cuca Ranch in later years was the Mendenhall family which called it Potrero Ranch. Today, the property is surrounded by the La Jolla Band of Luiseno Indians.