APRIL 2015 COLLIDING MONUMENTS Product Review Angle Points Vision to Design Traverse PC A question of ethics Lake Wobegon Trail
Completing the Lake Wobegon Trail Vision to Design» MATT PIKE
The urban areas in Stearns County, Minnesota, are like islands in a sea of corn, soybean and dairy farms. Through this bucolic setting runs the Lake Wobegon Regional Trail (LWRT) named after Garrison Keillor s fictitious lake a 62-mile (100-km), 10-foot (3-m) wide hike-and-bike pathway. It opened in 1998 and today stretches through central Minnesota, connecting in Osakis with the 55-mile (89-km) Central Lakes Trail. In addition to hiking and biking, one of the major usages of this trail is snowmobiling in the winter. As snowmobiling is not allowed within the St. Cloud metropolitan area, having a staging area in Rivers Edge Park (City of Waite Park) with ample public parking for trailering their snowmobiles is huge for metro snowmobilers. In 2012, a 3.2-mile (5.1-km) addition was commissioned to connect the LWRT to the municipal trail systems in the cities of Waite Park and St. Cloud, which connect to the west bank of the Mississippi River. The addition will also cross the Sauk River and utilize an active Burlington Northern Santa Fe (BNSF) rail corridor, private easements and a public road right-of-way. The LWRT extension project is a collaboration of the county s Parks Department, which led the effort to build the trail and has responsibility for maintaining it; the offices of the county surveyor and of the Map of the Lake Wobegon Regional Trail MAP COURTESY OF STEARNS COUNTY PARKS county engineer; and the state s Department of Natural Resources, which provided some of the funding. WSB & Associates was hired to do the engineering. Surveying services for the extension began in July 2012 and the plan is to complete it by 2018. Stearns County has approved it but still has to secure the land from BNSF. Aligning the trail required blending work done in CAD and in GIS, bringing the data into a county-wide model and then into a state model. Challenges included surveying in Garrison Keillor (left, on bicycle) in Osakis, MN, at the dedication of the joining of the Lake Wobegon Regional Trail and the Central Lakes Trail, August 2007 PHOTO COURTESY OF STEARNS COUNTY PARKS the Sauk River to plan a bridge adjacent to the existing railroad bridge, and surveying in areas covered by a heavy tree canopy. The Role of the County Surveyor Stearns County Surveyor Scott Marlin, LS, who has a degree in geography and a minor in GIS, helped create the county s GIS and dealt for years with water, soils, and planning issues before transitioning to surveying. He assisted the county in setting
up ties between its GIS, tax system and cadastre. His ability to integrate these systems was very valuable to the county, which encouraged him to become a surveyor and supported his investments in technology. Under Minnesota state law, county surveyors must be licensed land surveyors. Marlin has made full use of this legal authority to minimize the work he has to contract to private firms. His team sets up GNSS base stations, runs aerial photography and lidar flights, and does the ground control on each of the 200 targets needed to cover the county. When the county builds a new building, we do the platting from the preliminary topo work to the preliminary plat, to the construction staking, to setting up the grid for the contractor, to laying out the parking lot, he says. Marlin and his team have been an integral part of the planning and data acquisition to help implement the trail. They determined the trail s preliminary Stearns County, MN, surveyors deploying a remotely-controlled catamaran with an echo-sounder to map the bottom of the Sauk River PHOTO COURTESY OF THE STEARNS COUNTY SURVEYOR S OFFICE alignment; then, after consulting with the county engineer, they staked out parts of the alignment as a first draft for the consulting engineers to use. The data they collected included topography and topographic features, utilities, wetland delineations, section control, property corners and right-of-way monuments many of the features that the consulting engineers need to design the trail. The Equipment They Used Throughout the project, Marlin s team used a Trimble R8 GNSS receiver connected to Minnesota s Continuously Operating Reference Station (CORS) network, which operates using Trimble VRS technology, a Trimble TSC3 controller running Trimble Access software, and a Nikon total station. Since the project includes a bridge, it required detailed mapping of the river bottom. For this task, the team deployed the Trimble R8 on a small remotely controlled catamaran built by Frontier Precision, Inc. The catamaran features a high-accuracy echo sounder and connectivity with any Trimble GNSS receiver or robotic total station. We can stand on the shoreline while the boat is running in the water, said Marlin, and we can see every shot. We have cross sections in the river, so we re able to check periodically on the data that it s collecting. The most westerly portion of the trail would be on the existing rail bed, which made data collection fairly easy. We re able to use Minnesota s CORS network and VRS corrections, so we re able to collect data very quickly, Marlin said. However, as we move to the east we end up in an area where we have heavier canopy and the wetlands become a little more difficult to get through. When they are unable to see the sky they use their TSC3 controller in combination with their Nikon total station. Throughout the project, they coded each shot at the collection point for ease in processing in the office. Returning to the office, they import the data into Trimble Business Center software (TBC), which they use to remove outliers and check accuracy and alignment. We ve had to transition the way we develop our CAD data into using methods that will readily transport into the GIS world, Marlin said. To help keep the data entry more consistent, his team set up Plan information for the eastern end of the proposed extension of the Lake Wobegon Regional Trail. Information could be shared with GIS and design software packages. Processing the data Marlin s team collects the data on the TSC3 controller and briefly reviews it in the field. IMAGE COURTESY OF THE STEARNS COUNTY SURVEYOR S OFFICE
View in Trimble Business Center depicts survey data for a section of the proposed extension of the Lake Wobegon Regional Trail. IMAGE COURTESY OF THE STEARNS COUNTY SURVEYOR S OFFICE standardized code libraries within Trimble Access software. However, for this trail project they are collecting new features, such as wetlands, so they are adding them to the Access code library. The team exported the data and sent it to the engineering firm, which completed the design using MicroStation software. The design information could be imported back into TBC to check for alignment and accuracy, and then easily exported to the field controllers for staking. The importance of integration The ability to integrate different disciplines, technologies and models is the key to the success of this project. The combination of hardware, software, technical skills and collaboration between the parties is making the county and state tax dollars go further. Matt Pike has been writing about geospatial technologies for more than a dozen years. Prior to becoming a freelance writer, he was a research analyst for state and local government. He lives in the Pacific Northwest. In Case You Were Wondering Where the Heck is Lake Wobegon Anyway? T he Lake Wobegon Regional Trail doesn t actually go to Lake Wobegon. The lake and the town are quite, um, elusive. It s like the old saying, You can t get there from here. But in another, very real sense, you can get there from just about anywhere as more than 4 million people around the world do on most weekends by tuning in to A Prairie Home Companion (APHC) radio show. Each listener has a special place in his or her heart for Lake Wobegon and its citizens all created from the fertile imagination of Garrison Keillor. On the first PHC broadcast in mid-1974, Keillor introduced the studio audience (12 people) and the radio audience (number unknown) to Lake Wobegon the little town that time forgot, and the decades cannot improve. The town s storied location is somewhere in the middle of Minnesota. The specific spot is the subject of much research, rumor and good-natured civic competition numerous towns have claimed to be Lake Wobegon. But only Keillor knows and he isn t telling, although he did say that the town of Holdingford, which is on the LWRT, is most Wobegonic. He has also said that Lake Wobegon is not shown on maps because of the incompetence of surveyors who mapped out the state in the 19th century. (Of course, they didn t have Trimble gear back then.) Produced like an old-time radio variety show with a live audience, each APHC program includes a Keillor monologue about Lake Wobegon, almost always starting with Well, it s been a quiet week in Lake Wobegon, Minnesota, my hometown, out there on the edge of the prairie. Keillor then relates the latest news and gossipy tidbits about Lake Wobegon and its good but mostly shy citizens. The town and its surrounding farms are populated with people of primarily Scandinavian or German stock, most notably Norwegian bachelor farmers. The people and their daily doings ring true, especially if you ve lived in a small rural town in the upper Midwest. The monologue always ends with: Well, that s the news from Lake Wobegon, where all the women are strong, all the men are good looking, and all the children are above average. Back in 1974, Keillor thought the show would be something to do for a year or two, but it caught on and, in mid-2014, celebrated its 40th anniversary. A Prairie Home Companion is now broadcast on more than 600 public radio stations and overseas in Europe and the Far East. Based in St. Paul, Minnesota, the show hits the road for part of every year and has been broadcast from almost all 50 states and a number of foreign lands. By those measures, Lake Wobegon is everywhere. Minnesota is informally known as the Land of 10,000 Lakes. Perhaps several zeroes should be added to that number, just to include Lake Wobegon.