How GPS has helped a Texas surveyor to keep up with demand in his rural area.

For topographical survey work on larger tracts, Russell Rivers mounts his Thales ProMark2 survey system on his Honda four-wheeler and collects data in kinematic mode.
The survey business is booming in rural Texas and in recent months I've been taking on more jobs than I've ever handled in my brief time as a go-it-alone surveyor. Luckily, I've also found an affordable and highly capable GPS survey system to handle the new volume. It's a great time to be a surveyor, although it really always has been.

I began my career in surveying quite early-due to the influence of my father, who spent much of his career as a surveyor and a civil engineer. He is now retired, but he worked in the surveying industry for 38 years, and spent more than 15 of those as an area engineer for the Texas Department of Transportation (DOT) in Vernon. I followed in his footsteps and worked as a district surveyor for the Wichita Falls District of the Texas DOT for 15 years where I mostly performed right of way and design work.

About a year and a half ago, I struck out on my own. Today, I can say that my business is in great shape, and I'm doing much better than I thought I'd do this early in the game. There's plenty of development and refinancing going on in my area, which is creating several opportunities for me. Many farming properties and ranches are being sold, some being converted into hunting areas.

Most of my work has been topography and boundary surveying. In the beginning, I used a total station to perform this work. I had used some GPS equipment when I was at the Texas DOT and knew of its value and was familiar with its capabilities. I knew GPS would be useful in my work since I work in a lot of open environments, and I knew the equipment would be good for my solo use. My dilemma, especially since I was establishing my business, was that I couldn't afford the $20,000 to $40,000 I knew I'd have to pay for the kind of equipment the DOT used. I looked into used equipment and discovered those prices were quite high as well. As with any new business, I knew I was going to have to take some significant risks, but I just wasn't prepared to make that kind of equipment investment up-front.

With his ProMark2 survey system, Russell Rivers is able to handle the rural areas where sections are very large and corners are sometimes miles apart.

Seeking Ways to Work Faster

I knew I wanted to be able to work faster without making the huge investment for some of the expensive GPS systems. So, I did some research, finally settling on the Thales (Santa Clara, Calif.) ProMark2 survey system. It was an affordable option for me and offers centimeter-level accuracy and good navigation capabilities, all in the same system. I give the staff at Allen Precision Equipment credit for taking the time and effort to explain its advantages to me. I learned that it offered the kinematic and stop-and-go capabilities to do topographic work.

I was hesitant about the unit at first since it didn't offer the specific RTK (real-time kinematic) features I had used with the Texas DOT. I wasn't sure that having to post-process the data would be good for what I would be using it for. I asked myself whether I really needed RTK for the jobs I normally perform. RTK would be most beneficial with construction projects, primarily because of its stakeout ability, but my need for that type of capability-at this time anyway-has really been marginal.

Did I Really Need RTK?

I've gotten into construction surveying a little bit where RTK capability is especially helpful, but I still mostly perform boundary surveys. There's no doubt that the ProMark2 units are good for those boundary jobs and I get the extra benefit of RTK accuracy from the system. I'm able to handle the rural areas where sections are very large and corners are sometimes miles apart. With my new units, I don't have to traverse those sections with a total station, which makes a world of difference; I save days of time.

Resetting corners just isn't a factor. I can enter the coordinates of the corner into one of the units (even in State Plane Coordinates), tell it to "Go To" a corner using the built-in navigation feature, get to within a few feet of it, and usually find it quite easily. If I need to reset a corner, I set a couple of control points using either the stop-and-go or static function, then reset it from the new control points.

Before going out to perform a "stop-and-go" style survey, Russell Rivers initializes the ProMark2 rover with the base station set over a known point.

Proven Tests

At $5,500 for the two-receiver standard configuration system, I feel that it has paid for itself two-fold in just the short time I've owned it. I'm getting many of my jobs done three to five times faster than I did with the total station equipment. I've done 10,000- to 15,000-acre ranch surveys in a few days-projects that would have taken me weeks in the past. I recently surveyed a 14,000-acre ranch on rough terrain in Knox County that had two rivers and several streams running though it. I set the base station in the middle where the property was about three miles wide with the longest sections measuring about seven miles. The centrally located base station collected data while I used the stop-and-go function along with a Magellan (Thales) SporTrak Map GPS receiver to navigate to the section corners. I had one of the ProMark2 units make five-minute observations using the stop-and-go function to ensure that I had plenty of data. The entire field survey took approximately five hours-a huge improvement over the amount of time it would have taken using the conventional total station method, thus saving me time and my client money. With total stations, I'd have had to employ at least one other person, maybe two, and we'd have been limited by line of sight since the section corners are somewhat far apart. I had the whole apparatus mounted to my Honda (Torrance, Calif.) Sportrax 250EX four-wheeler to navigate around the rugged area. The ProMark2 also left me unconcerned about the many ups and downs on the property where I'd normally have to cut lines. The equipment allowed me to keep moving along efficiently.

The data obtained while using the stop-and-go or kinematic mode also allows me to record a vertical profile for the property I work on. That's very useful when the owner or the lender hasn't had the ability to see the terrain in that area, since the vertical data is helpful for planning fence line locations and quantities. The system also has a great ability to stay initialized. However, if I lose initialization, I still have the option of changing to static mode instead of returning to the base for reinitialization. The receiver is light-weight (a total weight of 7.5 lbs) and uses conventional AA batteries or rechargeable ones. It also has an external battery pack that holds four AA batteries. I can usually run the unit for a good 15 hours or more.

I recently performed a topographical survey on an open 140-acre field where the owners are planning an egg farm. Construction will include 20 buildings, each 60 feet wide and 600 feet long. The topo survey will help them to know how much dirt to cut and fill. I collected all the vertical data on the property in kinematic mode. I just mounted one of the ProMark2 units on my Honda four-wheeler and recorded all the data I needed. The cross section process only took about an hour and that included two separate runs for accuracy checks.

Upgrading for the Future

For now I'm using the two-receiver ProMark2 package. I'm tentatively planning on upgrading to three or four receivers in light of the amount of work I'm taking on. Using this equipment is fundamental to my process of creating a database, which eventually will contain most all of the section corners and subdivisions in my area, all of which will be on the State Plane Coordinate System. The extra receiver or two would allow me to use one receiver as a base and at least two as rovers, saving me considerable time, plus creating a much better network.

All this means that I'm maximizing the number of projects I can do. In 2003, I completed 55 projects using mostly total station equipment. This year, I've done 105 jobs just in the first six months. In this business, there's only so much of a backlog a surveyor can carry. Telling a potential client that I can do a job in six months just isn't an option. With my new equipment, I can usually schedule and complete a job within a week of the time a customer calls. I honestly believe the RTK GPS system has been a key element in allowing me to keep a tight schedule. The ProMark2 is helping me handle most all of the opportunities that come my way. I'm even starting to hear from people in surrounding counties. I want to be able to do all the work that comes my way. After all, it might not be there next year.