top of page
  • Writer's pictureDale Hill

June 2021 'Drive-By' Survey Marks

Updated: Jul 3, 2021

June provided a good mix of survey marks that fit my category of Drive-By Recoveries, I found a total of 20 this month and I had several "New" finds. Since injuring my knee on Memorial Day, my hiking activities have been put on hold which has allowed me to focus more on specific Survey Mark Scavenger Hunting (SMASHing) for marks on the National Geodetic Survey's GPS on Bench Marks Initiative. One of the hidden benefits of that activity is that I am driving by a LOT more survey marks! This month was a good mix of traditional discs, a few PLSS corner marks, and local "non-registered" marks. Overall, as of the end of June, I have recovered 437 marks, adding a total of 78 during June.

Quick Index of June Drive-By Recoveries


  2. RA 122 1967 (Ramona, CA)

  3. GWM 47 Benchmark (Bonsall, CA)

  4. T 723 REF MON (Ramona, CA)

  5. DX0269: U 723 (Ramona, CA)

  6. POWAY A-2 (Poway, CA)

  7. DC1130: G 321 (Poway, CA)

  8. DR6654: R 281 RESET 1980 (Lakeside, CA)

  9. DC0660: U 61 (Lakeside, CA)

  10. WCCR XP 2 (Lakeside, CA)

  11. S 55 ECC 1997 (Lakeside, CA)

  12. S 55 RP 2000 (Lakeside, CA)

  13. N.C.T.D. STATION CONTROL MONUMENT 2007 (Encinitas, CA)

  14. NE CORNER SECTION 24, TOWNSHIP 10S, RANGE 6E, SBBM (Borrego Springs, CA)

  15. DX3535: R 1326 1978 (Borrego Springs, CA)

  16. DX3536: Q 1326 1978 (Borrego Springs, CA)

  17. DX3545: S 1299 1978 (Thermal, CA)

  18. DX3547: T 1299 1978 (Thermal, CA)

  19. DW0230: G 577 1939 (Thermal, CA)

  20. DX0244: J 62 1927 (Santa Ysabel, CA)

While most of my recoveries are on hikes or specific outings where I'm looking for one or more specific markers, there are the ones that are just 'along the road'. I call these 'Drive-By' recoveries because I'm driving with my GAIA GPS USGS Topo map in 'follow' mode and I can see the benchmark notations along my route. It's mostly about keeping your eyes open and paying attention.

Many markers are located along active roadways, use common sense, take appropriate safety precautions, and exercise due care to avoid potential injury. If you choose to search for survey marks it is at your own risk. Please do not disturb or remove Survey Markers!

June 4, 2021 - Highland Valley Road, Escondido, CA


Due to traffic considerations, I had to go "the back way" to Poway for a doctor's appointment this morning. Highland Valley Road is a twisty, curvy road that connects Ramona to Escondido. On my way to the appointment, I noticed a section corner mark on my Topo map, I slowed as I went around the corner I could see a witness stake just off the road. I decided to take the same route home so I could recover the mark. This pipe cap was totally plain, the Registered Engineer had to stamp ALL the data on it! Once I saw the R.E. number in the triple digits, I knew this mark had been there a while. This number belongs to Ernest R. Childs and was issued sometime before 1930 (beginning in 1930, the county listed new licenses issued each Fiscal Year)

June 4, 2021 - Highland Valley Road, Ramona, CA

RA 122 1967

Continuing up Highland Valley Road into Ramona, I always liked this corner on HVR because of the big boulder sitting on the fence line. It just looks cool how the appears as if the fence goes through the boulder. As I slowed for the corner, I caught a witness post out of the corner of my eye. I pulled off the road as soon as I could, walked back to the mark, and recovered another in the "RA" series of survey marks.

June 6, 2021 - West Lilac Road, Bonsall, CA

GWM 47 Benchmark ~ 722 Feet Elevation

I spent the afternoon searching for GPS on Bench Marks Priorities along the SR 76 corridor in Bonsall and was only able to locate one on a list that included several. Rather than take the 15 Freeway home, I decided I'd take Old 395, a favorite route from my cycling days with the North County Cycle Club. I figured being an older road, I might also pick up some Drive-By Recoveries along the way. I spotted the usual symbol on my Topo for a benchmark on West Lilac road, since it wasn't too far out of my way I went to check it out. This was pretty cool because it was only the second disc that I've found stamped GWM, the other one I found was a benchmark I found on my hike to Palomar Lookout on the Oak Grove Truck Trail in Warner Springs. I'm not sure what GWM stands for, it could be the surveyor's initials or just the identifier used for that particular survey, but both benchmarks are U.S. Geological Survey discs that are pre-stamped with "Cooperation with the State" on the inner ring.

June 8, 2021 - Third Street, Ramona, CA


Every time I drive into Ramona via "the back way" (Vista Ramona Road to 3rd Street), I pass by DX0301: T 273 (presumably) It shows up on my Topo as being near the corner of 3rd and G Streets and the datasheet indicates it's mounted in boulder. Using the directions and coordinates, the best I can tell is that the boulder that it's mounted on is in the backyard of a fenced-in private residence. Just to be sure, on the way home one afternoon I parked on the side of the road and walked down the street to take a closer look at the boulders on the street side of the fence, no mark. As I returned to the truck, I found this San Diego County Engineer Reference Monument for T 723, the next best thing!

June 8, 2021 - Vista Ramona Road, Ramona, CA

DX0269: U 723

When I was researching the location of T 723, I came across the datasheet for U 723, the next mark in that survey project, and had made a waypoint on my map for the anticipated location. On a roll from finding the Reference Monument above, I decided to stop and look for U 723. It was a little bit off the road, near the T intersection where Old Julian Highway turns North and Vista Ramona Road begins and continues on straight. As stated in the datasheet, it was located in a good-sized rock outcrop and was in good condition.

June 15, 2021 - Old Pomerado Road, Poway, CA

POWAY A-2 and DC1130: G 321 (LOST/DESTROYED)

The G 321 benchmark was identified on my Topo map as BM 491 with the "X" on the side of Old Pomerado Road, I had been out that way previously to find a GPS on Bench Marks priority (DC1128: PITCH) and given the location of that disc and it's elevation, I thought it was the one referenced on the map. After further research, I learned G 321 was located a little further down the road. So on the way back from running errands in Poway, I went by to see what I could find. Following my GPS on the topo map, I drove to the spot marked by the X and parked. I was a few feet away from a culvert and I could see a disc in the top, I was stoked that I had found the mark so easily...until I looked at the mark and saw that it wasn't G 321! I'd located a pretty plain survey disc stamped POWAY A-2 in basically the exact spot where I'd expected to find G 321. After documenting the first find, I started walking South scanning the side of the road for any signs of the mark.

At the intersection of Old Pomerado Road and Old Stone Road, I found a piece of the concrete monument that G 321 had been mounted on, the block of concrete was placed neatly next to a culvert headwall on the southern side of the intersection. There was no evidence of the rest of the monument near where this had been set, so my guess is that someone found this piece and just placed it there.

It's possible that this monument was destroyed when the culvert was built, especially since the A-2 mark is in the exact location where G 321 should have been. I searched online records for any information on the A-2 mark or previous references to the G 321 mark but came up empty. Perhaps when I have nothing better to do, I will check with the Engineering Department for the City of Poway to see what records they have, but for now, I'll just chalk up a unique find with the POWAY A-2 disc and write-off G 321 as lost/destroyed.

June 24, 2021 - SR 67, Lakeside, CA

DR6654: R 281 RESET 1980

The nice thing about marks that are set in sidewalks and bridges is that they tend to be exactly where the Topo map shows them to be! This Vertical Control Mark was marked by a BM symbol on my map, there was a convenient place to pull off the road just past the bridge, and the mark was where I expected to find it. Of course, the surveyor's paint around the mark eliminates the guesswork 😂

June 24, 2021 - Willow Road, Lakeside, CA

DC0660: U 61

The only way I knew this was U 61 was based on the coordinates and the "To Reach" information in the datasheet, as you can see in this picture it's pretty well scratched up. It's located behind the convenience store/gas station (Union 76 I believe) that is at the corner of SR 67 and Willow Road. The recovery entry on the datasheet was dated 1967 and it was described as being mutilated back then!

June 24, 2021 - Wildcat Canyon Road, Lakeside, CA

WCCR XP 2, S 55 ECC 1997, and S 55 RP 2000

These three marks were really "bonus" finds while looking for a benchmark noted on my topo map that was close to the intersection of Wildcat Canyon Road and Muth Valley Road in Lakeside. This particular section of Wildcat Canyon Road is narrow and often busy, so I've never found an opportune time to stop, however today, I pulled off and parked on Muth Valley Road. As I was walking back to where I anticipated the benchmark to be, I passed these three survey marks, all stamped washers held in place with PK nails and epoxy. The first one, WCCR XP 2, is just a survey point on Wildcat Canyon Road, the other two are San Diego County marks that are related to the USGS Benchmark I was searching for, S 55. The "RP" tag stands for Reference Point, and the S 55 ECC is an Eccentric Station. I never did find the USGS disc, it may require a more thorough search as the area where it is supposed to be is very overgrown.

June 25, 2021 - La Costa Avenue, Encinitas, CA


Today I was really focused on recovering priority marks for the GPS on Bench Marks initiative and didn't even look for any Drive-By Recoveries, but this was an unavoidable "Walk Over Recovery" 🤣 I walked right over it on the sidewalk as I was on my way to recovering OC 145 (DX1173). On top of being a no-brainer find, it was a new type of recovery! You’d think it’d get more difficult finding new survey marks, this was recovery number 426 and the first North County Transportation District (NCTD) marker that I’ve found.

This is located on La Costa Avenue, mounted on the sidewalk, on the bridge that crosses the tracks of the LOSSAN Rail Corridor. NCTD purchased the corridor in 1992. LOSSAN stands for the Los Angeles to San Diego rail corridor. There is a dedicated manual published by SANDAG (San Diego Association of Governments) that discusses the LOSSAN Corridor Design Criteria (note: large PDF!) which includes procedures for surveys and monumentation, based on what I read, I can expect to find many more of these 2” discs along the corridor, in easily accessible public locations such as this. I’ll have to pay more attention now! 🙃

June 27, 2021 - Henderson Canyon Road, Borrego Springs, CA


For some reason, I just really like these U.S. General Land Office (GLO) discs. Perhaps it's because the GLO origins date back to 1812 and its role in overseeing the surveying of the West and the development of the Public Land Survey System (PLSS), or that it was the forerunner of what we know today as the Bureau of Land Management or BLM.

The GLO was placed under the Department of the Interior when that department was formed in 1849, it was merged with the United States Grazing Service (established in 1934) to ultimately become the Bureau of Land Management on July 16, 1946.

Whatever the case, I always like to find these and this was the fourth GLO disc that I've recovered, each of them denoting a spot on the PLSS grid.

This corner mark was very close to the Calfornia Historical Marker for Peg Leg Smith and my first GPSonBM recovery of the day, DX0471: 11 AAR

June 27, 2021 - Borrego Salton Seaway, Borrego Springs, CA

DX3535: R 1326 1978 and DX3536: Q 1326 1978

R 1326 was really my first Drive-By Recovery of the day, I had just passed the Borrego Valley Airport and rounded the first 90º corner going by Dump Road when I saw the Witness Sign ahead off the side of the road. I grabbed my pipe wrench and recovery kit bag and walked the 25 or so feet to the mark. It was cool to find another "1326" Vertical Control Mark, I've found two other VCMs in this survey line on previous trips, one of those was below ground in a pipe-like these two (DX3539: M 1326 located at the Villager Peak Trailhead parking area) and the other (DX3541: K 1326 was mounted in a boulder not too far from where I started my Memorial Day hike that ended abruptly with a torn ACL)

Vertical Control Mark Q 1326 (above) had to be the EASIEST find of the day 🤣 Located in a wash not too far before reaching the turnoff to Fonts Point, the concrete monument once buried so only a few inches were above the sand, was now completely exposed due to erosion and its location in the middle of a wash. The disc is still mounted into a 1.2 meter (about 4-foot) steel rod driven into the ground, inside a 4-inch PVC pipe, capped with a screw plug, so you can't just pick up this chunk of concrete and walk away with the monument and disc.

June 27, 2021 - Borrego Salton Seaway, Thermal, CA

DX3545: S 1299 1978 and DX3547: T 1299 1978

These two marks were easy-peasy "Witness Sign in the middle of the desert recoveries" located on the Borrego Salton Seaway just past the Calcite Mines as I was headed East. Both of these were less than 20 feet off the side of the road and the witness signs were a dead giveaway to their location. I had to dig out the screw plug for T 1299 as it was buried in the sand and not immediately visible. They were like bookends to one of my GPSonBM priorities (DX0441: AD 29) that was located on the road between these two marks.

June 27, 2021 - CA-86 North, Thermal, CA

DW0230: G 577 1939

Up to this point, I located all of today's DBRs by spotting the Witness Sign (or post) first. While this one had a standard roadway paddle right in front of it, I saw the monument first. It's uncommon to see such a tall concrete monument, most of the time you only see the top 4-6 inches of these monuments if they're not flush with the ground. I was headed toward a GPSonBM Priority that wasn't too far away and I was scanning the side of the road for a place to pull over when I spotted this monument. At first glance, I thought it was the mark I was looking for (DX0449: G 517), but it was a new Drive-By Recovery.

June 27, 2021 - SR 78, Santa Ysabel, CA

DX0244: J 62 1927

This was one of those Topo Benchmarks that seemed to elude me. Located right along SR 78 in Santa Ysabel, near the T-intersection with northbound SR 79, this is a mark that I pass by EVERY TIME I head out to the desert, regardless of which way I'm going. Of course, this intersection is where Dudley's Bakery, the Julian Apple Pie Company, the Farmhouse 78 Restaurant, and Don's Market (my go-to snack stop when passing through Santa Ysabel) are located. I've stopped on more than one occasion and walked around the area looking for this mark with no luck. After my first few searches, I assumed that it was inside the fence for the antique shop and I'd have to look for it when the shop (and gate) were open.

Perhaps with all the dedicated SMASHing that I've been doing lately, my "Spidey-Senses" have been honed to a finer point. I was on my way home from Borrego Seaway/Salton Sea SMASH and just happened to be looking at that side of the road as I drove through when I saw the tell-tale concrete monument! Honestly, after successfully recovering this mark, I don't know how I missed it before! Still, a great way to close out a good month of Drive-By Recoveries 🙃

Recent Posts

See All


bottom of page