- SPECIAL REPORTS
- THE MAGAZINE
So much is happening in the area of GIS that I’m not sure where to start. Let’s start with some of the good news. With the power of current computers, GIS software can be run on any fully enhanced computer. The days of specialty machines are, for the most part, history. The more modern the computer, like a Pentium 4 with a gig of RAM, the better job it will do, but current computer costs should not keep anyone out of the GIS market. Other good news is that many cities, counties and even some states are building large sets of data and making them available on the Internet. From your office, you can research records of original government land office plats and some original notes along with tax records. In some cases, you can search for deeds. Most of this work can even be done from a field location with a cell phone and Internet connection. I think that within 20 years most data required of surveyors will be available online.
Another important development in the area of surveying-related GIS is the technical advancement of data gathering. Tools such as LiDAR that use a visible light laser to pulse the ground can provide vertical data to meet most 2-foot mapping specifications, and in some cases, carefully controlled flights can provide 1-foot contour mapping or better. Currently, this technology is mostly cost-effective over large geographic areas. I am sure this will also change over time. Already the cost of mapping per acre is greatly reduced over conventional stereoplotter mapping. A number of companies are researching digital aerial cameras. The most recent to arrive on the scene is a digital scanning aerial camera that operates much like the scanner connected to a computer. This camera scans a seamless dataset more than a mile wide and about any length you can store the data. It provides the client an almost instant digital orthophoto layer. Needless to say this is also going to greatly reduce the cost of datasets. And it can provide picture data in 4-inch pixel size.
As I travel around the country I find more and more surveyors are being hired to provide control or collect field data that make up modern GIS systems. Surveyors need to understand where datasets that make up modern GIS systems come from and know their accuracies.
What Does This Mean?With all of these great advancements, like data on demand, can there be a side to the picture that we as surveyors should be concerned about? I can best answer this question by relating a story that recently happened in my home state. I received a call from a surveyor who told me the county in which he practices had recently passed a requirement that all subdivision plats be submitted in State Plane Coordinates, including a digital file along with the Mylar map. About a week after meeting these requirements, he received a call informing him that the coordinates he submitted did not fit the county’s GIS system and that he would have to adjust his coordinates to fit the system.
He called to ask my opinion on what to do. I wish all the calls I get had such a clear-cut solution. The county worked themselves between the proverbial rock and a hard place, I believe. I told him to meet with the people at the county office, point out that they had required the State Plane Coordinates and that he had provided them within survey accuracy. If he were to change his coordinates, they would no longer have State Plane Coordinates, plus he showed them on the recorded plat and could not change them for any reason since the plat was signed. The solution to the situation was for the county to adjust its coordinates to his survey accurate data as required by law.
While I may have helped to solve that scenario, the problem runs much deeper when a surveyor wants to mix the accuracy standards from two different kinds of surveys. The original mapping for the GIS system may have had an accuracy standard for orthophotos of one meter. The surveyor brought in his survey data accurate to one hundredth of a foot, as required by the Alabama Board for Licensure. Can you see the conflict? What makes matters worse is that the scaling GIS software tools read the coordinates to three decimal places. The GIS technicians believe that they have that level of accuracy. To make matters worse yet, many GIS system managers buy GPS systems and believe they are working to survey grade accuracy—some even using a handheld. Some residents pick up copies of data printed out that show fence lines and property lines and believe they can find their own boundaries.
What can surveyors do about some of these developing problems? Only the local surveyor with a one-on-one dialog with local GIS managers can solve these problems. Ask that any GIS maps sold contain some statement as to the source and accuracy of the data, perhaps a statement that the maps are not surveys and that only a professional surveyor can determine the location of boundaries. Explain the difference between recreational GPS and survey grade GPS. There are many examples across the country in which people are hired to provide GPS data who are not surveyors or engineers. Make your board of licensure aware when this happens. Work toward changing the laws in your state so only a surveyor can provide survey-grade GPS data.
Citizens’ groups in some areas are fighting the posting of courthouse data on the Internet. This is the time you as surveyors need to be supportive of your local officials, and point out that data is now available at the courthouse and that putting it on the Internet allows you to operate more efficiently thus saving money. If you don’t speak up, you are in danger of losing one of the greatest benefits of GIS.
Addition to “Are you properly insured?” May 2003In my last column, I talked about several different kinds of insurance. I saved the topic of disability insurance so I could dedicate a little more space to the understanding of this type of insurance. The term disability insurance is, for the most part, self-defining. What separates the many different types are their uses and functions for your company. Individual disability insurance policies are structured to replace between 45 to 60 percent of gross income on a tax-free basis during a period of illness that would last longer then a normal sickness covered by sick leave or annual leave.1 Providers of this type of coverage break out into two different groups: those who provide coverage for professional staff and those who provide coverage for technical or “blue-collar” occupations.
Professional disability insurance is most commonly provided by company owners on each other, where the illness of one member would put a great hardship on the remaining owner. Owners can tailor insurance for business overhead expenses, which can help the company pay expenses if an important principal is unable to function in his or her role of company leadership. The bottom line is to determine how much you want to spend. Including some coverage for employees as part of their insurance package is a nice benefit. Owners can control costs by having a longer than average grace period before the benefit kicks in. There is a considerable amount of additional information at the website www.about-disability-insurance.com. You can also receive a quote. (Please note: I have not used this company; the information is provided for comparison shopping only.)
1 About Disability Insurance website by Steve Crawford, www.about-disability-insurance.com.