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Pre-Conference Workshops

Sign Up for Both Workshops and Save! Registration bundle rate for morning and afternoon workshops: $150 (listed as full day pricing in Event Brite).

Ground Truth for the Future: Low Distortion Projections and the State Plane Coordinate System of 2022

Sunday, April 22, 2018

8:00 a.m. – 12:00 p.m.

Workshop Lead & Speaker: Michael Dennis, RLS, PE, M.ASCE, NOAA/NOS/National Geodetic Survey

Map projections are distorted — it is a fact of life. The crux of the problem is linear distortion: the difference between true horizontal “ground” distance and its projected representation. This difference often exceeds 1 foot per mile (20 cm/km) for State Plane and other existing published coordinate systems. Such linear distortion can be problematic for various geospatial products and services, including engineering plans, survey plats, construction staking, as-built surveys, and facilities management. Linear distortion cannot be eliminated, but it can be minimized using low distortion projections (LDPs) – although some situations can prove challenging for designing LDPs that perform satisfactorily. This workshop shows how LDPs can be designed to achieve optimal performance even over relatively large areas with variable topographic relief. Importantly, the design procedures are based on the same conformal map projection types used for the new State Plane Coordinate System of 2022 (SPCS2022): Lambert Conformal Conic, Transverse Mercator, and Oblique Mercator.

The workshop also provides an overview of the history of State Plane and current plans for development of SPCS2022, including proposed options for states and territories to adopt LDPs as part of SPCS2022. Beyond consistency with SPCS2022, another benefit of using those existing map projection types is that they are compatible with engineering, surveying, and GIS data. Because they can be rigorously georeferenced, LDPs can be used directly to represent conditions “at ground” in GIS and CAD platforms. A resulting notable benefit is that LDP datasets can coexist with other geospatial data without resorting to approximate “best-fit” transformations or other “rubber-sheeting” acts of desperation.

Primary Objectives
• Explain map projection concepts to enable evaluation of projection types and characteristics that are most suitable for surveying and engineering applications
• Give overview of the State Plane Coordinate System of 2022 (SPCS2022), including the history State Plane, plans for SPCS2022, and the role of LDPs in SPCS2022
• Provide detailed methods for designing LDPs that optimally minimize linear distortion
• Describe characteristics of various existing methods for minimizing map projection distortion and how to evaluate their performance
• Show how to make use of existing LDPs in their software and workflows
• Discuss documenting LDPs to facilitate data transferability

Additional Ticket Purchase Required

Registration Fee: $100
PDHs: 4

ASCE Standard 38-02: Substructure Utility Location: The design, the Engineer, and the Surveyor

Sunday, April 22, 2018

1:00 – 5:00 p.m.

Tom Pilarski, PLS, M.ASCE, Psomas
David Moritz, PLS
Anissa Voyiates, P.E.
Richard Moore, PLS
Matthew Wolf

ASCE Standard 38 is a guideline for the collection and depiction of existing subsurface utility data. The collection and depiction or the lack of collecting and depicting of subsurface utility data can positively or negatively affect the design of a project. In this presentation, we will have a brief overview of ASCE Standard 38-02 and look at substructure utility locating from 4 perspectives. In the overview of ASCE Standard 38-02 we will discuss how following this guideline can make it easier for the engineer, the surveyor and the subsurface utility detector to locate, mark out, map and design a project. By walking through a project, we will present the design perspective from the engineer and how the location of subsurface utilities can assist them in their design We will discuss the Land Surveyors perspective on how the locating of subsurface utilities can easily be done in the mapping phase. We will also look at the substructure utility locator’s perspective on the utility locating tools that are available and the accuracies one can expect from those tools. We also will discuss the perspective of the licensing board for the State of California and how they view substructure location and mapping. The intent of this presentation would be to show how the locating of utilities up front in the mapping phase of a project, you can reduce RFI’s in the construction phase of a project.

Additional Ticket Purchase Required

Registration Fee: $100
PDHs: 4


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