GIS Position Paper

Much has been written and continues to be written regarding "Geographic Information Systems" or as it is commonly known, "GIS". The acronym is bantered about with a belief that everyone has an equal understanding and awareness of exactly what it is. To some it is a technology or a sophisticated software or as some definitions indicate, a GIS can "contain major components including data input, data storage and retrieval, data manipulation and analysis and data reporting subsystems". It can be "a management system which can collect, store and retrieve spatial data, identify locations meeting specific criteria, explore relationships, analyze data for effective decision making, select and pass data to analytical models and display information". It is a system of computer hardware, software and procedures "to support capture, management, manipulation, analysis, modullary and display of spatially referenced data for solving complex planning and management problems." If there is a common thread to any of these comments, it would probably be that a GIS has a computer software system to operate so it can perform functions that are impractical or impossible to do manually. It is a marriage of graphic and non-graphic data that deals with space. Within a GIS, queries can be performed on the map, attribute data or both. No other system has this type of capability.

Finally, a GIS is an excellent tool for effective decision making. It allows decisions to be based on the best ability to model the data to develop a new set of spatial relationships. It can answer questions posed as to what would happen if a particular phenomenon changes. What will the impact be on surrounding areas? Are there better options?

Because of the far-reaching aspects of a GIS...effective systems are being utilized for a multitude of applications by local governments and others to measure crop potential, for the management of forests, the planning of communications networks, to monitor urban growth, the development of infrastructures and in emergency services..., to note a few, there exists the possibility that not everyone has the same understanding of just what a GIS is, what it can be, what its needs are, and what it is not.

Through this position paper, the Michigan Society of Professional Surveyors will provide an overview of a GIS and the role the Professional Surveyor can provide in the development to make it an even more useful tool.

Maximum effectiveness of a GIS requires cooperation and coordination between all agencies that are involved from the original project planning, implementation and finally, maintenance. Whether they are local units of government, private utilities, associations or organizations involved in land or real estate, consultants, engineers or Professional Surveyors, they all must be involved. As may be necessary, other organizations such as the National Geodetic Survey and the respective State Advisor may be involved.

If we can assume that an effective GIS is basically a mapping system, then it is imperative that the basis of the GIS is founded on an accurate map. Each type or perhaps, layer of the GIS, demands accurate and properly located control monuments. If accuracy is not a part of the GIS, the information created will not correctly relate to positions on the ground or to each other.

More than 75 percent of the information produced and utilized in local governments has a geographic component, so GIS plays an increasing role in local governmental units.

To quote an old axiom from the early days of computers "garbage in, is garbage out". The same may be true with a GIS.

With the increasing technological advancements in the computer world and the rapid advancements in mobile telephones, GIS technology will allow decisions to be made in the field while the data is being collected.

Using the definition of practice as it relates to Professional Surveying, the Michigan definition states the practice means "providing professional services such as consultation, investigation, testimony, evaluation, planning, mapping, assembling and interpreting reliable scientific measurements and information relative to the location, size, shape or physical features of the earth, improvements on the earth, the space above the earth, or any part of the earth, and the utilization and development of these facts and interpretations into an orderly survey map, plan, report, description or project. The practice of Professional Surveying includes all of the following:

"(I) Land surveying which is the surveying of an area for its correct determination or description for its conveyance, or for the establishment or reestablishment of a land boundary and the designing or design coordination of the plotting of land and the subdivision of land.

"(ii) Geodetic surveying which includes surveying for determination of the size and shape of the earth both horizontally and vertically and the precise positioning of points on the earth utilizing angular and linear measurements through a spatially oriented spherical geometry.

"(iii) Utilizing and managing land information systems through establishment of datums and local coordinate systems and points of reference.

"(iv) Engineering and architectural surveying for design and construction layout of infrastructure.

"(v) Cartographic surveying for the making of maps, including topographic and hydrographic mapping."

If we ask the basic question, "does this definition, as noted in Michigan law, dictate that Professional Surveyors should control GIS information?" After all, it states it includes "utilizing and managing land information systems through establishment of datums and local coordinate systems and points of reference".

According to the Michigan Department of Consumer and Industry Services, Board of Professional Surveyors, the licensing unit of the State, the Board "holds that the establishment of datums and local coordinate systems based on the Public Land Survey System is the role of the licensed Professional Surveyor. Through education and examination, the Professional Surveyor is uniquely qualified to manage local Land Information Systems (LIS). It is the Board’s policy that the base map of a GIS/LIS referenced to section corners in the Public Land Survey System must be accomplished under the supervision of a licensed Professional Surveyor."

Since only a licensed Professional Surveyor has the authority to establish or reestablish a boundary, then the answer is quite obvious. However, what if a boundary is not the issue? Perhaps the boundary is only being referenced through the many base layers of the GIS document.

Ultimately, the decision rests on what effect the inclusion of a Professional Surveyor with a GIS may have on the result. If for example, a governmental agency determines that property is either within or outside of a zoning area, they are determining a boundary, which under Michigan law they are unable to determine. The problem as it relates to protection of the public health and safety of our citizens could be impacted by that decision. In that example, then a Professional Surveyor can provide the necessary determinations to make that decision.

The trend perhaps should be a coordinated effort between the governmental agencies which may be in the forefront of development of a local GIS to understand the role the Professional Surveyor can provide to ensure their GIS has eliminated as many potential problem areas as it can. To do anything less, would undermine the concept of what a good GIS can do for an area.

Most land information systems require high accuracy data. Local government GIS programs require large scale, high accuracy, high resolution geographic and map data. By beginning with accurate information developed by the Professional Surveyor, as the GIS evolves and begins to serve the many needs of the diverse interests, the data will continue to meet the needs.

In more cases than not, GIS systems have a tendency to start as a small system and become large as more components are added or more information is attempted to be gleaned from the project. For example, a demographic study may not require positional accuracy with a high level beyond 50 to 100 feet, plus or minus. When the plan or program is extended to other applications, the data is not sufficient to reflect the accuracy requirements of the new use.

For those groups that are not familiar with high accuracy requirements, technology cannot be a substitute. In other words, if the foundation is not based on sound practices as generally utilized in the surveying profession, when the basics are advanced to higher levels of utilization, conclusions cannot be expected to retain the same level as accuracy. If data from different sources is combined, it does not increase the accuracy. In fact, if anything, it may decrease the accuracy. If, for example, survey accuracy data were to be overlaid over data on soil types with an accuracy of +/- 100 feet, the result would not be better than +/- 100 feet. If thousands of dollars of high accuracy data were placed on a low accuracy map, the high accuracy data does not upgrade the low accuracy map; instead, the high accuracy is reduced to the level of the lowest map data.

One problem that can surface however, is one of funds. Budgets have a tendency to downgrade the accuracy levels. Combined with time frames , data availability and the skills of those involved in all phases of the GIS, doing it right, becomes ignored in order to achieve the GIS.

Since other areas of expertise are required to develop, utilize and maintain an effective GIS, each component must reach for the highest levels of accuracy. Surveying is one of those fields in the many disciplines to be incorporated. The Professional Surveyor has the knowledge and skill for creating accurate and reliable GIS databases. Why would any one want anything less?

A coordinated effort between those involved in the GIS and Professional Surveyors can be achieved by open communication and cooperation and the recommendation of utilizing the skills of the Professional Surveyor may be critical in the initial establishment of the GIS and the long-range value of what has been created.

Since the end result may be far removed from the initial plans for the basic GIS, it is important that all phases of the GIS, from the beginning surveyor’s measurements, to the interpretation of the data, must be achieved at the highest level possible.

The Professional Surveyor can be an integral member of the development of the GIS. They bring an understanding of the land, of the need for the high levels of accuracy, of the preparation of maps and for the communication and cooperation needed to bring a concept to reality. Therefore, GIS should be another area of interest for the surveying community to ensure that their expertise can be of benefit for all concerned.

By taking the time to do it right from the beginning, time and unnecessary expense will be eliminated from the need to do it over.