GPS

GPS (Global Positioning Systems)

Before the creation of our current GIS/GPS system, we had split water and sewer maps into four books, two for water and two for sanitary sewer information. Each book consisted of approximately 500, 16 inch by 18 inch pages and weighed about 20 lbs each. That’s a huge book to use when out in the field, especially in some of the vehicles where you can’t physically open the book in the cab of the trucks. Our crews literally had to get out of the vehicle and put the book on the hood to use it. Not the best solution when it is raining, windy or snowing outside.

The process of updating twenty-three sets of books was very time intensive. The update process required all of the nearly 2,000 original map sheets to be printed, copied, collated and assembled in the map books. Unfortunately, by the time we get the book updated and out to the field, it was already outdated by three to four weeks. That’s weeks of missing corrections or additions to our maps that will not be added until we do another complete update.

The procedure for finding the correct page in these books was by using an index sheet and finding which quarter section you needed. Often the information that you wanted to look at was at the edge of that map sheet you just found so it was likely you would have to flip between two, three or even four map sheets to find the necessary information. Another disadvantage was the inability to see water and sewer information in relation to each other on the same page.

In the early 90’s the decision was made to create the water and sewer maps using computers instead of drawing these maps with pen and ink. Microstation© was chosen as the computer-aided drafting (CAD) software allowing us to draw and link information to a database.

Our GPS equipment, per vehicle, consists of: one tablet computer, one GPS antenna/receiver, one copy of the GeoLink software and a daylight readable 15 or 17 inch touchscreen monitor. The tablet PC can be undocked and taken into the field if needed. The operator can choose between a water project, sewer project or combo project. The combo project has been a great improvement for the construction crew, as now they can easily see information such as what side of a manhole a water service is on. As an operator drives to a site the map is constantly centered on the screen so upon arriving at a site utility information, parcels, addresses and air photos if desired are displayed. Updates are made by copying new files from a CD. The future plan is to allow updates to be automatically performed over a wireless network connection.

The next step in our process will be the use of high accuracy GPS for data collection.