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GPS on Benchmarks 2021  By: Sam Mutt, plS

        We need your help!

          Most of us have transitioned from “making ground measure-  dated horizontal framework that is closer aligned to the global
        ments” to using “GPS” to make control networks and even map-  reference frame, and a purely gravity-based vertical component.
        ping using GPS.  This tool has enabled us to save time and effort  The nGS is seeking new values on published benches, to apply
        in our pursuits, which translates to being more competitive and  to the new geoid model, to produce this new and improved ge-
        meeting the increasing demands of tight budgets.       oid-difference model.
        How would you like to become even more efficient?      We only have 6 months left for the GPS on BM 2022 Transforma-
        We need to provide up-to-date measurements on the bench-  tion Tool Campaign. The NGS will only use data submitted by
        marks in our State to the nGS, the outcome will yield improve-  December 31st, 2021. In Washington State we have a very large
        ments in the vertical component. The nGS is moving towards a  number (776) of Benchmarks that still need GPS observations.
        reference framework that is earth-centered-earth-fixed: an up-  here’s the list of GPS on benchmarks need by county and chapter:

        CASCADE COLUMBIA CHAPTER             NORTH CENTRAL CHAPTER                NORTH PUGET SOUND CHAPTER
            Kittitas County (32)                 Chelan County (23)                   King County (30)
            Klickitat County (none)              douglas County  (69)
            Yakima County (16)                   Grant County (46)                SOUTH CENTRAL CHAPTER
                                                 Okanogan County (75)                 Adams County (27)
        INLAND EMPIRE CHAPTER                                                         Benton County (32)
            Asotin County (7)                NORTHEAST CHAPTER                        Franklin County (23)
            Columbia County  (10)                Ferry County (23)
            Garfield County (4)                  Pend Oreille County (13)         SNOHOMISH CHAPTER
            Lincoln County (38)                  Stevens County (26)                  Snohomish County (22)
            Spokane County (20)
            Whitman County (34)              NORTH OLyMPIC CHAPTER                SOUTH PUGET SOUND CHAPTER
                                                 Clallam County (25)                  Pierce County (17)
        LOWER COLUMBIA CHAPTER                   Jefferson County (21)
            Clark County  (none)                 Kitsap County (9)                SOUTHWEST CHAPTER
            Cowlitz County (3)                                                        Grays harbor County (27)
            Skamania County (5)              NORTHWEST CHAPTER                        Lewis County (21)
            Wahkiakum County (5)                 Island County (8)                    Mason County (none)
                                                 San Juan County (1)                  Pacific County (17)
                                                 Skagit County (21)                   Thurston County
                                                 Whatcom County (8)

          The GPS on Benchmarks effort needs you!  Please
        contact: 1.) Larry Signani at Larry.Signani@nv5.com or
        Sam Mutt at (425)345-1452 or secretary.snohomishl-
        saw@gmail.com if you would like to help out. There
        are still many benchmarks that need to be recovered,
        observed, and reported on in order to improve the
        nGS Transformation Tool. The deadline is set for de-
        cember 31, 2021 and is fast approaching. n

        NOTE: As an incentive, those individuals or chapters sub-
        mitting GPS data for the most number of benchmarks
        will receive one free registration to the upcoming LSAW
        2022 Annual Conference, to be held in Vancouver, Wash-
        ington, March 2 – 4, 2022. See Sam Mutt for details of
        that award.









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