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into account when using a CBL to check our EDMs? I will move forward with the discussion about CBLs that are established for today’s work and equipment. No matter what you think I am saying herein, I am all in favor of a CBL. Temperature is still a factor, in conjunction with the barometric pressure. I am sure most everyone is aware of this, but it has baffled me over the past ten or so years that I have been
Over the past year I have been trying to convey more of the philosophical side of surveying than the technical. Today is no different. However, I will touch on how the two really do relate. As many of you should be aware, our Sacramento Chapter has been endeavoring to construct an Electronic Distance Meter (EDM) Calibration Baseline (CBL). I will begin by pointing out that a CBL is only as good as the procedures
used when checking your equipment against it. Our predecessors could recognize and accept there were flaws and imperfections in their equipment, and it is only right that we must follow suit and accept this fact in our own equipment. In the past, temperature and tension was taken into account, as, measurements taken could be different than the true length. These were the considerations that previous surveyors were faced with, but what is it we must take
A Survey Baseline: By: William J. Wilson, PLS
where Philosophical meets Technical
INS IDE TH IS
I S SUE :
Conference 2
North Counties
Seminar
3
Minutes 5
Baseline
continued
8
Engineer Day 10
membership 11
Focal point M A R C H 2 0 1 0
A PUBLICATION OF
THE SACRAMENTO
AREA CHAPTER
OF THE
CALIFORNIA LAND
SURVEYORS
ASSOCIATION
March 4, 2010
Drinks at 5:00
Dinner at 6:00
Spaghetti Factory 12401 Folsom Blvd. Rancho Cordova, CA 95610
P A G E 2
From CLSA Discussion Board The officers of the Central Valley Chapter have been working on a chapter web site. This will complement the web pages for our chapter that will be hosted on the main CLSA web site. You can view the preliminary web site for the Central Valley Chapter here: http://www.californiacentralvalleysurveyors.org/ If your chapter does not have a website and you’re
interested in getting one online, I can share my site
design as a template and help you get web server
services set up. Just let me know. :]
F O C A L P O I N T
Not going to conference?
Come to the March Sacramento Chapter
meeting for the complete report.
P A G E 3 M A R C H 2 0 1 0
Northern Counties Chapter, CLSA Presents:
Records of Survey and the Business & Professions Code for the California Surveyor Speakers:
Aaron Smith, PLS & Dave Woolley, PLS FRIDAY, MARCH 26, 2010 Gold Country Casino, 4020 Olive Highway, Oroville, CA 95966 REGISTER EARL Y Space is Limited (First 80 registrants) Conference Sponsor Mid Valley Title and Escrow 601 Main Street Chico, Ca. 95927 530-893-5644 www.midvalleytitle.com This course is presented as professional development for licensed professionals and those preparing for licensure, but is also an informative course for individuals or businesses that depend upon the work of the surveying professional. Note: Speaker fees have been donated. All proceeds to fund Northern Counties scholarship and the CLSA education foundation. Member in Advance $130 at Door $170 Non-member $170 $210 Student $ 55 $ 80 Contact: Northern Counties Chapter CLSA c/o Roger Wilkins, Secretary - Treasurer 6328 County Road 15 Orland, CA 95963 Phone: 530-514-0581 Fax: 530-934-4158 E-mail: [email protected]
P A G E 4
F O C A L P O I N T
Speaker of the evening: Bill Hofferber and his wife, Elena.
To the side: Dave Goodman shows off a Surveying Quilt made by his daughters. (If you look really close there is a picture of Dave surveying in Egypt.)
Below: Rich Aviles, Steve Martin and Dave Goodman during the presentation of the 2010 Dave Goodman Scholarship.
Minutes
P A G E 5 M A R C H 2 0 1 0
Called to Order with introductions around the table.
President Oscar Jarquin: Welcomed everyone. He reported the following results from the executive committee meeting: Approved purchase of external hard drive for the Secretary Approved the donation of money to CLSA to help cover expenses of 3 student volunteers for Conference Discussed the development of a Budget Purchase stuff for a basket for CLSA Education Foundation auction
Vice President Bill Telling: Absent but it was reported that the March meeting is going to be at the Old Spaghetti Factory in Rancho Cordova and April will be at Logan’s Roadhouse in Natomas. Secretary Annette Lockhart: Discussed the budget and ways to spend money. Possibilities discussed were to preserve Dave Goodman’s Egyptian work or several ideas for conference.
Treasurer Nick Labedzki: Absent but reported the following numbers: Checking 3306.08 Savings 5032.60 CD 5000.00 PayPal 4686.00 Total 18024.68
Board Representative report Rob McMillan: The CLSA Conference is coming up – It looks like a great event! CLSA is continuing their efforts on the issue of the office of “County Surveyor” in LA. The CLSA Professional Development Program is now a FREE member benefit. If you want the wall plaque, it will cost you $25. The 2010 Officers, Executive Committee members, and Committee Chairs were installed, including former Sacramento Chapter member Tom Taylor as Treasurer, Annette Lockhart is the Chair of the newly established GIS Committee. Rob McMillan will continue to Chair the Education Committee. Bill Telling will continue to serve on both the Education and Workshop Committees. CLSA, will be celebrating Land Surveyor's Week March 21-27, 2010 (the same week as the National Land Surveyor's Week). CLSA’s membership is down about 10% statewide. Members need to pay their dues, and encourage others to join at both the State and Local levels. Our strength is in our numbers. BPELS had a 42% decrease in LSIT Applicants in October 2009, while EIT applicants were down only 5%. Caltrans had 19 staff pass the CA PLS exam in 2009. Also - Move over for Caltrans vehicles – It’s the law! The 2010 Trig*Star program is ramping up – Get out there and visit those high schools! The strength of a Chapter is in the involvement of it’s members. Participate!
P A G E 6
Committee Reports: Habitat for Humanity- no report Membership- John Scarpa- will be calling from a list of membership (sent list around for verification of information); Motion to bring membership classifications to be in line with state. Motion to table, mo-tion to table passed. Government Liaison- no report Professional Practices: Neal Jones- working on first case and added two members. Workshop Coordinator-Bill Telling 2010 LS Review (Annette Lockhart reporting) 40 students attending. We have great presenters. LS Application Workshop- Done FEMA Elevation Certificate- DWR is the lead on this. FEMA talk at conference. Baseline Committee- Stanley King- Location found, but need to get an encroachment permit to access from City of Sacramento. In progress. Unfinished Business New Business- Engineer’s Day at the Mall on February 20- John Turner, Justin Lambert and Rich Aviles to help. CSDS to supply us with a modern instrument to display. Vote to acquire 3 BLM manuals from Central Office. Steve Martin talked about the scholarship distribution. $28000 was given at Fresno and $46000 altogether. Presented the Dave Goodman scholarship to Sacramento City College student Richard Aviles.
Presentation by CLSA Presiident-Elect Bill Hofferber.
F O C A L P O I N T
Minutes continued
Being a Corporate Sponsor is a reasonable and cost effective way to support the Sacramento Chapter of
CLSA. This corporate support is vital to sustaining our chapter activities, monthly newsletter and
scholarship fund. If your firm would like to become a Corporate Sponsor please contact the editor at:
[email protected] or (209) 518-9962.
GONZALES SURVEYS, INC.
DBE/SMBE UNION SIGNATORY
6240 West 6th Street
Rio Linda, CA 95673
(916) 768-6303
11661 Blocker Dr.
Ste 200
Auburn, CA 95603
(530) 885-7072
1788 Tribute Rd. Ste. 200 Sacramento, CA 95815 (916) 927-2400
7300 Folsom Blvd., Ste 203
Sacramento, CA 95826
2590 Venture Oaks Way
Sacramento, CA 95833-3288
(916) 569-2500
3301 C Street #100-B
Sacramento, CA 95816
(916) 341-7760
Morrow Surveying 1450 Harbor Blvd. Ste. D
West Sacramento, CA 95691 (916) 372-8538
5979 Freeport Blvd. Sacramento, CA 95822 (916) 421-3465
Burrell Consulting Group, Inc. 1001 Enterprise Way, Suite 100 Roseville, CA 95678
2001 Broadway, 3rd Floor Oakland, CA 94612
(510) 834-2001 www.hjw.com
2295 Gateway Oaks Drive, Suite #140
Sacramento, Ca. 95833
Ph: (916) 923-5820
1300 Ethan Way, Suite 300
Sacramento, CA 95825
(916) 921-9033
P.O. Box 661412
Sacramento, CA 95866
916-489-3528
David B. Karoly, LS 7849
Boundary & Topographic Surveys
GPS Control Surveys
Now located in Sacramento
R/W Mapping, Topos, Boundaries
A full-service DBE/SBE firm
916-419-2070
Cooper Thorne & Associates Engineering & Surveying 3233 Monier Circle Rancho Cordova, CA 95742
3380 Industrial Blvd., #105 West Sacramento, CA 95691 (916) 374-8575
Radman Aerial Surveys 6220 24th Street
Sacramento, CA 95822 (916) 391-1651
Thanks to Our Corporate Sponsors for Supporting the Sacramento Chapter
Baseline Continued back in California that few of the survey crews at the places I worked were provided with barometers and thermometers. Additionally, they were not enlightened as to exactly what the Parts per Million (PPM) setting on their Total Stations was for and how to adjust it using said barometers and thermometers. Why are we worried about a CBL when some crews are not measuring an accurate distance in the first place? The pressure changes, from month to month, day to day, hour to hour, or even location to location. Even if you don’t see it, it is changing. I have checked the Temperature and Barometric pressure each time I set up my instrument, or periodically throughout the day, if I am set on the same point for an extended period of time. I have
been able to duplicate a measurement months even years after the initial distance was derived. However, I have beaten my head against the wall when crews return with differences of five-hundredths or more from one day to the next. A CBL is constructed with a series of monuments at progressive lengths. This is to check the different wave sizes necessary to travel different distances, but if the current conditions of the medium (air) the laser is passing through is not taken into account, distances will vary. I am not here to rant about this old topic, but I wanted to point it out and suggest anyone that does not have a barometer and thermometer as part of their equipment inventory, or does not use them regularly, find some old articles on the subject or crack open a survey book. This brings us to another matter where CBLs are concerned: All of the CBLs I have seen/used or read about here in California have a precision problem as far as I am concerned. They have all been built flush with the surface. This opens up a whole other can of worms when it comes to making accurate measurements or even precise ones for that matter. With monuments that
are flush with the surface of the ground, you must use tripod legs to set up your Total Station and prisms. Then, to make sure you are over the exact point, you rely on an optical plummet (I am assuming no one uses an old-fashion plumb-bob anymore). Is anyone willing to admit to the inherent problems associated with this scenario? First, the Tripod legs: how often are the joints checked for being tight? Beyond that environmental factors can change them throughout the day? Temperature, moisture, or a slight breeze can all have the slightest or even a not so slight affect on the position of your equipment. Second, the optical plummet: is that adjusted or checked on a regular basis, or most importantly, right before it is used to perform checks at the CBL? Yeah, sure, you can say I am within a hundredth or two when you use the CBL, but how do you know that any errors caused by your faulty equipment did not correct your measurements back to a better reading? We as Surveyors are legally defined as Expert Measurers. When we cannot see or choose to ignore inherent problems
F O C A L P O I N T
Baseline Continued
P A G E 9 M A R C H 2 0 1 0
associated with measuring, how can we accept this title? Before moving back to California, I had the opportunity to work in Utah for a number of years. This gave me a chance to see and use the CBL that was established in the Salt Lake City (SLC) Area (recently destroyed). I was also afforded the opportunity to talk with one of the BLM Surveyors that helped to establish it. The SLC CBL was a series of Concrete Monument pillars, which stood about three and a half to five feet tall in the area between I-15 and a frontage road several miles south of SLC. Each of these pillars had a notch in the top with a seventeen inch square (17”) aluminum plate with a small hole drilled in it. This hole precisely fit a lug that is threaded on one end to screw into the tribrach on the bottom of your Total Station or Prism mount. As the center of the hole is the measurement point for each monument, there is no need to be concerned about Tripod legs or optical plummets being out of adjustment. At this point, the only additional equipment variable that needs
to be addressed would be your leveling, either bubble or electronic. If a question can exist as to the accuracy of either, your
measurements will also be subject to question. I would love to see a CBL established here in the Sacramento Region, but I would also love to see local Survey crews and their employers educated as to exactly how to use such a tool. There are many factors that need to be addressed for its proper use, how those same factors are related to our day to day work, and how to apply corrections for them on a regular basis. Perhaps you do not see a need for a CBL in our area. Perhaps you think what I .have said herein is a good argument against such a CBL. Anytime a question can be brought up concerning any surveyors’ level of expertise, all surveyors pay the price. Any question regarding your ability to
accurately and precisely measure a distance will be greatly diminished once a CBL is established and you begin using it
on a regular basis. Where the rubber meets the
road, survey philosophy and
technology, one is useless
without the other. I hope I
have stirred some passion
herein. If I have, please let us
know via a letter to the editor
concerning my comments, or
especially if you would like to get
involved with constructing and
measuring the CBL.
1075 Creekside Ridge Dr. Ste 200
Roseville, CA 95678
(916) 788-8122
P A G E 1 0
F O C A L P O I N T
Baseline Update by Stan We believe we have found a suitable location after many months of searching. The new location is just east of Rio Linda, between Bell and Hunters Creek Drive, immediately west of the North Sacramento Bike Trail. We are waiting for the insurance certificate from CLSA Central
Office. I will submit the Encroachment Permit Application . The City has been very helpful. I am not anticipating any more problems. The monument boxes have been ordered from Berntsen. We have the
brass cap marks from NGS. The weekends of March
19, March 26 April 2, and
April 9 are current
possibilities.
Engineer Day
at
the Mall
Tom Cardenas from CSDS sets up with Justin and Rich looking on!
P A G E 1 1 M A R C H 2 0 1 0
sac-surveyors.org
CLSA SCLSA SCLSA SCLSA SACRAMENTOACRAMENTOACRAMENTOACRAMENTO ---- 2010 C2010 C2010 C2010 CHAPTERHAPTERHAPTERHAPTER OOOOFFICERSFFICERSFFICERSFFICERS
Oscar Jarquin (916) 201-0992 [email protected] Bill Telling (916) 769-8258 [email protected] Annette Lockhart (209) 518-9962 [email protected] Nick Labedzki (916) 445-8695 [email protected] Clayton Guiraud (916) 653-2698 [email protected] Bill Telling (916) 769-8258 [email protected] Rob McMillan (760) 846-4491 [email protected]
New address: PO BOX 160234 Sacramento, CA 95816
FOCAL POINT ADMINISTRATIONFOCAL POINT ADMINISTRATIONFOCAL POINT ADMINISTRATIONFOCAL POINT ADMINISTRATION
Editor Annette Lockhart (209) 518-9962 [email protected] Workshops Bill Telling (916) 769-8258 [email protected] Webgeek Jeremy Dean [email protected]
The FOCAL POINT is a publication of the Sacramento Area Chapter of the California Land Surveyors Association and is pleased to publish letters from land surveyors and other interested persons on subject matter relevant to the land surveying profession. Please include your name, address and daytime phone number. Views expressed are the opinions of the individual writers and are not necessarily those of CLSA, the Chapter, or the editor. FOCAL POINT accepts no responsibility for the accuracy of the information given. Letters may be edited and published in any format. All letters submitted become the property of the Focal Point. Due to space restrictions, FOCAL POINT reserves the right to hold letters for publication at a later date.
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