Submitted by: Jason R. Houle, PLS & Rock County Surveyor
Date: May 5, 2015
Recently, I served on a committee comprised of members of the Wisconsin County Surveyors Association, (WCSA), to define Survey Grade, (SG), coordinates as they would apply to the Wisconsin Land Information Program, (WLIP). During the development of this definition, several issues arose concerning Public Land Survey System, (PLSS), monuments as they will serve as the framework for the Statewide Parcel Map, (SPM). Entwined in any conversation I’ve been part of about the SPM has been spatial accuracy; perceived, actual, what is expected and what is needed. Different groups address this topic from their point of view however, collaboration among stakeholders is required if there are hopes of successfully rolling out an SPM in 2017. The stakeholders are many in this endeavor and the Department of Administration, (DOA), will define those elements required. This paper focuses on why I believe spatial accuracy grades should be defined within the context of the WLIP and for future PLSS remonumentation.
Conversations and correspondence with colleagues, representing various groups within the geospatial industry around the state, led me to believe that additional accuracy standards need to be developed in addition to SG. The standards could serve to guide those entities maintaining a Geographic Information System, (GIS) and parcel datasets, (PD’s) in Wisconsin now and in the future. My opinions are formed not from one perspective rather, are a blend of the interests of all parties for whom I advocate or am a member of; Rock County, the Wisconsin Land Information Association, (WLIA – Board Member), the WCSA, (member), and the Wisconsin Society of Land Surveyors, (WSLS – member). Collectively, many Geospatial Professionals are represented by these groups and I believe there is common ground that can be found relative to the PLSS and spatial accuracy that addresses some but, not all, of their interests; the 2017 SPM deadline requires it.
This paper details what I believe should be accuracy standards for the SPM, with justifications for the same. Also, other points are made that give context to the standards when applying them in a GIS or SPM. Prior to delving into the standards and for the benefit of those not familiar, I want give general information concerning the PLSS, how PD’s are created and maintained and the statutory directives given the DOA.
Most Wisconsin lands are subdivided according to the Public Land Survey System. The geodetic reference framework for the Statewide Parcel Map will be the corners of the PLSS; the PLSS must be connected to the National Spatial Reference System, (NSRS). Rock County uses the Wisconsin Coordinate Reference System, (WISCRS – Rock Datum), for all current work. Wisconsin is fortunate to have Wisconsin Height Modernization Monuments, (HMP), monuments installed and maintained by the Wisconsin Department of Transportation, (WDOT), geodetic unit; HMP monuments allow for an easy connection to the NSRS. The recent SG definition recommends that coordinates obtained by way of remonumentation projects funded with WLIP dollars be in a coordinate system permitted by WI. Statute 236.18(2).
Other areas of the State not subdivided by way of the PLSS should assess their situation and coordinate the submittal of their data with the DOA.
To the extent possible, parcel lines are anchored to the PLSS system on a County by County, municipality by municipality basis. Typically, parcel lines are built from deeds and information beginning or commencing at PLSS corners; this record data needs to be manipulated so as to be seamless County/municipality wide. The results are reasonably accurate and PD’s allow a GIS to function for its many intended purposes; an intended purpose cannot be determining property boundaries. From a practical and legal standpoint, even the most carefully constructed PD anchored to precisely measured PLSS corners does not represent boundary/property lines. Those corners and lines can only be determined by a Professional Land Surveyor, (PLS), that must follow all applicable federal, state and local statutes, rules and ordinances.
Parcels within a GIS are created from record data that could be decades and/or centuries old. An original plat of Any City, WI. could be created from a subdivision plat described as commencing at a PLSS corner followed by general Northerly-Southerly-Easterly-Westerly directions, coupled with distances in chains and links, leading to a Point of Beginning. Suffice to say, there is some discrepancy between the mapped locations and the actual monuments in the ground set during the original, or subsequent, surveys. Discrepancies that are to be expected, cannot necessarily be quantified and do not represent sloppy work or negligence. Also, most lots and blocks in older areas have subdivisions where tenths of feet, feet, or more are prorated through the block when lots are surveyed by PLS’s. Those proration’s, (a 66 ft. platted lot may be 65.46’), will most likely not find their way to a GIS or PD. Additional layers of ambiguity arise when considering the errors, omissions and ambiguity of some existing legal descriptions. Lastly, when surveying an existing parcel, PLS’s must follow Administrative Rule A-E7, (Minimum Standards for Property Surveys), and their surveys represent the opinion of the property boundary between surveyed and adjoining parcels; an opinion certified by a PLS. Property lines in any GIS or PD are no more than a graphical representation of record data and is not a substitute for a survey; a fact typically acknowledged via a disclaimer prior to viewing a GIS. Spatial uncertainties do not dilute or diminish the reliability or high level of complexity and expertise needed to create and maintain a data rich GIS. A GIS has advanced tools that allow data embedded in the background to be manipulated and analyzed in countless ways. “The illusion of simplicity” has been used when referring to GIS; a term I wholeheartedly agree with.
The SPM will need to be composed of PD’s in the same coordinate system. Across the State multiple coordinate systems are being used and that data will need to be converted for use in the SPM. I will not get into details about various systems but, will state that all data must be submitted in a format, clearly defined, that can be recognized by commonly used GIS software.
The directives given the DOA, as found on their website, are as follows.
16.967(3) DUTIES OF THE DEPARTMENT
The Department shall direct and supervise the land information program and serve as the state clearinghouse for access to land information. In addition, the department shall:
(h) Establish an implementation plan for a statewide digital parcel map
In coordination with the department, the creation, maintenance, or updating of a digital parcel map.
No later than January 1, 2017, the department shall submit to the members of the joint committee on finance a report on the progress in developing a statewide digital parcel map.
DOA must create an implementation plan for a statewide parcel map, is responsible for the development of a statewide digital parcel map, and must coordinate parcel mapping with counties.
Given the intended purpose of and SPM and the accuracies required to allow it to function, versus accuracies required for progressive PLSS remonumentation, I propose the following.
For reference, what follows is the recently collaboratively agreed upon definition for SG coordinates.
Coordinates collected under the direction of a Professional Land Surveyor, in a coordinate system allowed by 236.18(2), and obtained by means, methods and equipment capable of repeatable 2 centimeter or better precision.
Members of WCSA that worked on this definition were Dave Tlusty – Langlade County Surveyor; Terry VanHout – Brown County Surveyor, Tony Dallman – Lincoln County Surveyor and myself.
I believe SG is a term unique to the Land Surveying profession and should only pertain to WLIP funded PLSS remonumentation. Requiring SG coordinates, while narrowly defining circumstances when MG coordinates are allowed, would be a responsible use of WLIP funding. Requiring anything less that SG or MG would be a disservice to the concept of private property ownership, citizens across the state and PLS’s now and for generations to come.
Circumstances that would allow for MG coordinates, (trees, foliage, very remote locations, etc.), provide an “out” in those cases where pursuing SG coordinates would cause an undue hardship. If a PLSS corner is in the middle of nowhere and obscured by trees/forest but, evidence is found that allows for the perpetuation of the same, MG coordinates may be a viable alternative absent much undue time spent traversing. I cannot envision a scenario where anything less than MG coordinates should be allowed when performing PLSS remonumentation. In the majority of locations and in order to remonument lost/obliterated corners, normally accepted surveying practices either will be, or must be, employed. That work requires an adherence to Instructions, Statutes and rules that require traversing and/or GNSS/GPS equipment; methods “capable of” the SG definition. Rules and/or justifications for allowing MG coordinates should be created so undue hardships are not interpreted to be a lack of modern GNSS/GPS equipment, contractors exceeding their quoted amount in remonumentation contracts, needing to walk to an area not obscured by foliage, etc., etc.
There is not a statutory requirement for coordinates to be provided per A-E 7.08. Also, unless other PLSS corners are used as evidence for proportioning; directions and distances to other corners are not required, per A-E 7.08 (3) (h). Given those facts, I do not support requiring survey grade coordinates on PLSS corners in all cases. Terrain, tree-cover, accessibility, etc. can cause undue hardships. Also, there are not vocal voices from other Geospatial Professionals advocating that position. As a County Surveyor I have a responsibility to maintain the PLSS and advocating for SG and MG coordinates allows me to do that. Additionally, allowing the MG definition contributes towards a more spatially accurate PD and permits valuable WLIP dollars to capture as much PLSS remonumentation work as possible.
Properly perpetuated PLSS monuments are my first priority. Second, coordinates. I believe in some cases the point of diminishing returns is reached in the pursuit of SG coordinates; to the detriment of other areas needing PLSS remonumentation.
I believe this term can apply to PLSS coordinates and/or PD’s. No parcel map should be portrayed as anything better as no matter how good the PLSS framework is, the parcels rely on record information, (Deeds, maps, etc.), that can be 5-10-50-100 years old. Also, the interpretation of deeds and creation of the PD’s may be performed by those who are not surveyors. Furthermore, there are entities that maintain a GIS who have invested in Mapping Grade GIS equipment who do not have a PLS on staff. Lastly, there are erroneous and ambiguous legal descriptions out there and it is not the role of cartographers and/or GIS personnel to resolve them. Cartographers and GIS personnel are not surveyors, title research professionals, attorneys, etc. and they cannot act in those capacities. Spatial uncertainties within GIS will be with us forever, whether or not they’re constructed based on SG or MG coordinates.
As a starting point for conversations, I would propose the following for an MG standard:
Coordinates in a system recognized by commonly used GIS software, (1) obtained by a Global Navigation Satellite System, (GNSS), or Global Positioning System, (GPS), device capable of repeatable sub-meter precisions, (manufacturers specifications), or (2) derived from Public Land Survey System, (PLSS), monument records or Surveys filed per WI. Statutes used as control to graphically depict other similarly filed or recorded Surveys, Deeds, Certified Survey Maps, Subdivision Plats, Right-of-Way Plats, Transportation Project Plats, or other public records, for use in a Geographic Information System, (GIS).
I believe this term can apply to approximate PLSS corner locations and/or PD’s. The unfortunate reality is that due to the current state of some County PLSS monuments and the looming 2017 deadline, UG coordinates may need to be incorporated into the GIS and PD’s maintained by some entities. For now. I strongly recommend and believe Land Surveyors and Geospatial Professionals across all disciplines should support a progressive PLSS remonumentation program that would utilize WLIP strategic grants in the future. The goal would be an ever increasing percentage of PLSS monuments with SG coordinates or, in a limited circumstances, MG coordinates.
As a starting point for conversations, I would propose the following for an UG standard:
Coordinates in a system recognized by commonly used GIS software, (1) obtained by a Global Navigation Satellite System, (GNSS), or Global Positioning System, (GPS), device capable of repeatable 1-5 meter precisions, (manufacturers specifications), or (2) use information including, but not limited to, public records, traveled way locations, fence locations, occupation limits or aerial photography as control to graphically depict Surveys, Deeds, Certified Survey Maps, Subdivision Plats, Right-of-Way Plats, Transportation Project Plats or other public records, for use in a Geographic Information System, (GIS).
I believe that from now until 2017 all stakeholders should be focusing on conformance with Act 20 by way of complying with DOA requirements. That involves using the most reliable data, (Currently available or in the short term), to produce the most spatially accurate datasets possible. The reality may be that the DOA is more concerned with database content than precise spatial accuracy. Justifiably so. Once success is achieved, (defined as a statewide parcel map in-place by 2017), and funding is available, surveyors and the broader geospatial industry should advocate for progressive PLSS remonumentation programs. Funding, full or in-part, may be possible through strategic initiative grants.
The ideas proposed herein are starting points for the development of definitions I feel are required for the successful implementation of the SPM.
While advocating for my positions, Rock County taxpayer dollars are spent wisely, I promote the interests of the WLIA and remain true to my surveyor roots and organizations to which I belong.
The views and opinions expressed herein are mine and not those of Rock County.
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