Kern County High Point Trip Report
Date: August 4, 2003
Objective: As part of some hikes I was planning to do between Mounts Piños
and Abel, do some Kern County relative high point measurements using relative
altitude differences from a digital altimeter aided by a GPS receiver,
(building on the work of Dave Covill and Gerry Roach) in trying to resolve which of the
three candidate high points should prevail.
Conclusions: The highest point on Sawmill is clearly the eastern rock outcrop,
not the western rock cairn. However, the Kern County highpoint is not here but
on the Piños northwest slope based on updated elevation data for
Mount Piños itself.
Equipment: Magellan GPS 315 with 2001 software update to take advantage of the
relaxation of "selective availability" and have distance readings under 0.1
mile expressed in feet rather than hundredths of a mile. All readings are in
WGS84 datum and bearings are relative to true north.
Lat/long readings are in degrees, minutes and thousandths of a minute (dd mm.xxx).
$300 Peet Brothers Barigo temperature-compensated digital altimeter with three foot
(1 meter) readout every second. Hiking (hockey) stick calibrated as a long yardstick for
accurately measuring short distances (like rock cairns and outcrops).
Topographical Map - Digital TOPO for Santa Barbara area (Version 1.2.2)
copyright 1997 by Wildflower Productions.
Technique: After setting an approximate elevation using the GPS, take
differential altitude readings with the digital altimeter at both Sawmill
Mountain and Mount Pinos candidate sites. The GPS is not extremely accurate in
elevation and the altimeter will vary slowly over time or distance due to
atmospheric conditions, so accurate ABSOLUTE measurements separated by
significant amounts of time or distance are not possible. But points a short
walk apart can be compared on a RELATIVE basis using the digital altimeter.
Since the altimeter reads with a 3 foot gradient, it dithers between adjacent
readings. So I took readings for one to two minutes in each set and averaged
the dithered values in proportion to the amount of time each was displayed.
The day was clear with only light winds. I camped the previous night at McGill
Campground in order to get an early start to avoid the midday sun, thermals, and wind.
I started hiking from the Nordic Ski Center at the crack of dawn
(5:40 AM) and hiked directly to Sawmill.
Sawmill: I arrived at the trail junction rock duck (34 48.783, 119 09.901) at
7:04 AM. I climbed the faint path a total of 55 vertical feet and 275 yards at
a bearing of 285 true to the large rock cairn (34 48.818, 119 10.077) at the west
end of the summit plateau. I then took altimeter readings here and then at the
natural rock outcrop 125 yards to the east (34 48.819, 119 10.001).
I then returned to the western rock cairn to take a second set of readings here and
then went back to the rock outcrop for a second set of readings there.
I kept the altimeter in the shade to avoid heat transients across the altimeter.
After adjusting for the height of the western cairn (which is 3.5 feet above the level
high dirt on the east side and 3 feet above the natural rock base on its north
side) and the eastern outcrop (2.5 feet above the dirt on its west side)
I concluded that the top of the eastern outcrop was about 6-12 inches above the
top of the cairn. However, in any case, the top of the cairn is not a valid highpoint.
I could easily take the top two or three feet of rocks off in a minute,
or could build it up by another foot or so in five minutes.
Since only natural rock formations count, I would claim that the top of the eastern outcrop
is a good 3 feet above the rock base under the western cairn! Case closed.
Regarding the absolute elevation at Sawmill, the X on my digital TOPO map for
Sawmill's 8,818 foot summit occurs at (34 48.800, 119 10.032) which I found on the
summit plateau between the two high point candidates, 65 yards at a bearing of
233 true from the eastern outcrop and 85 yards at a bearing of 116T from the western cairn.
It is in an unremarkable area a few yards south of the faint path
connecting the two candidates, that is clearly a few feet lower than the ground
at either of the candidate points. However, it is only 30 yards from a natural
general ground rise to the west toward the cairn at an old fallen log with a few
basketball-size rocks scattered about looking sort of out of place. Could this
be the 8,818-foot point? I was not able to find a survey marker, and from the
topo map, the lack of a triangle or BM at the elevation number means that there
isn't one. Afterwards, speaking at length to an USGS expert in Missouri,
I found out that since the elevation on the topo map is slanted (i.e. italicized)
it means that it was determined by aerial stereo photography rather than ground survey.
The accuracy of such measurements is 10% of the contour interval,
which on the topo map is 40 feet, so the determined elevation is between 8,814 and 8,822 feet.
Furthermore, the point measured is not necessarily the highest point on
the summit, but rather some point within the highest contour line which can be
readily identified in multiple stereo views.
If the nominal 8,818-foot measurement was made where indicated on the topo map,
then the elevation of the top of the eastern outcrop is 8,818 + 2 to 3 feet of
gain to the outcrop + 2.5 feet of natural rock outcrop = 8,823 ±4 feet or 8,819
to 8,827 feet. I signed both registers and left the area at 7:50 am.
Piños: I arrived back at Piños at 8:40 am. I found two official survey benchmarks.
One is located at the rock outcrop just north of the security fence,
6 feet east and 3.5 feet below the obvious top rock of the summit. I measured
this marker (10 satellite GPS) as (34 48.767, 119 08.719). It is dated 1941 and 1967.
Its location compares extremely favorably (within 12 feet) with the
coordinates of the Mount Piños benchmark on the TOPO map: (34 48.766, 119 08.721).
I used this marker for all my measurements because the second marker (dated 1941)
is 35 feet northwest of the first in a circle of rocks, placing it about
35 feet from the TOPO location (it appears to be about the same elevation as the
marker at the outcrop).
The candidate Kern highpoint here (34 48.805, 119 08.778) is near a big tree on
a 3.5 foot rock outcrop (measured above the flat dirt on its south side) located
120 yards at a bearing of 310 true from the first Piños marker.
Again taking two sets of measurements at each site, I concluded that the Kern
outcrop top is 18 feet below the Piños outcrop top.
Since both 8,831 and 8,837 feet have been mentioned as elevations for Mount Piños,
after returning home I decided to try to obtain the latest official estimate.
The USGS expert in Missouri led me to the National Geodetic Survey Data Sheets and
help me interpret them.
Data sheets for all of the National Geodetic Survey controls as well as the
control history are available on the web at http://www.ngs.noaa.gov/cgi-
bin/datasheet.prl. Click on “DATASHEETS” under the column headed “Retrieval
Links”, next click on “PIDs”, next enter “EW7674” (the data sheet number for
Mount Piños) in the first box and click on “Submit”, next click on “EW7674” to
highlight it, then click on “Get Datasheets”. On the first page of this six page report,
under “Current Survey Control” it indicates that the latest elevation
based on the latest geoid model (GEOID99) for the Mount Piños
marker monument is 8,847 feet. This would be for the marker,
not the actual peak next to it.
This leads to an elevation estimate for the peak itself to be 8,847 +3.5 (to the
top of the outcrop) ± 4 (uncertainty) = 8,846.5 to 8,854.5 feet.
Subtracting off the 18 feet down to the top of the Kern outcrop on the Piños slope
gives its elevation as 8,828.5 to 8,836.5 feet. Since this entire elevation range
is higher than the Sawmill candidate of 8,819 to 8,827 feet, the highest point
in Kern County is the rock outcrop on the northwest slope of Mount Piños.
By the way, the metal post on the Piños slope was GPS-measured as latitude
34 48.785, which is about 18 feet north of the TOPO map latitude of 34 48.782 for
the county line here. This places this Kern highpoint candidate rock outcrop
clearly north within Kern county. I left the area at 9:50 am.
Author: Jon Buyan