Learn how Emlid can deliver GNSS accuracy for your GIS projects

Accurate positioning is crucial across many GIS industries, from city planning to precision farming. Thanks to modern GNSS accuracy, GIS professionals now collect data with unmatched precision. This article explores how high-accuracy GPS is applied in urban planning, agriculture, and beyond, showing how reliable positioning enhances decision-making and project outcomes.

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Why GNSS accuracy matters for modern GIS workflows

Not all GIS applications require centimeter-level accuracy. Tasks like mapping general features, such as store locations or service area boundaries, can typically be handled with the 3–5 meter accuracy provided by consumer-grade smartphone GPS.

However, many GIS use cases demand much higher accuracy. When documenting underground infrastructure, designing site-specific features, or conducting scientific research, sub-meter or even centimeter-level accuracy becomes essential. In these situations, the difference between a rough estimate and actionable spatial data can be critical.

Fortunately, modern survey-grade GNSS receivers, like those from Emlid, make it easier than ever to achieve high-precision results. These receivers integrate seamlessly with popular GIS tools like QGIS and ArcGIS Field Maps, enabling GIS professionals across a range of industries to bring survey-level accuracy into their everyday workflows.

Real-world experience using GNSS in GIS projects

Smart infrastructure mapping

Semir Kahrimanovic and the Bozmaps team from England, UK, began digitizing a site maintenance reporting system for a team that previously relied entirely on paper maps. The team had no GIS experience and struggled to accurately locate features, such as broken fences or leaking taps, across numerous plots. Using mobile phones and basic GPS, they created layers in ArcGIS Field Maps to enable image capture and note-taking tied to geographic points.

However, the inherent inaccuracy of the phone’s GPS, especially in areas surrounded by hedgerows and trees, made this setup insufficient for precise mapping needs, particularly when identifying underground infrastructure.

Emlid Reach GNSS receivers for utility mapping — *Bozmaps team using Emlid Reach GNSS receivers*

Recognizing the need for higher accuracy, Semir decided to enhance the workflow by integrating a GNSS receiver. He tried the Emlid Reach RS2+. He conducted a full-day training session for a team, and then they went into the field to map underground utilities. The difference in data quality was significant.

With the Reach RS2+, Semir dramatically improved the accuracy and efficiency of their workflow, achieving 10-30 cm (3.9 to 11.8 inches) accuracy with a standalone Reach receiver. When the Reach RS2+ is combined with RTK corrections, the team can can get 1-2 cm (sub-inch) accuracy.

This level of detail was essential for accurately locating hidden infrastructure. The team benefited from clearer records, faster reporting, and a more professional GIS approach, all enabled by the improved integration of GNSS technology into their mobile mapping efforts.

“We increased the accuracy of our mobile mapping workflow by pairing ArcGIS Field Maps with Emlid Reach RS2+, and it was super quick and easy,” says Semir.

*The hedgerow map captured with ArcGIS Field Maps and Reach RS2+*

Locating ancient Maya ruins

Mark Willis is an archaeologist and independent researcher who collaborates with universities and renewable energy companies across the globe. For his work, especially in drone-based LiDAR mapping, he relies heavily on Emlid GNSS equipment like the Reach RS2+ and Reach RS3 receivers. One of his primary applications involves flying LiDAR-equipped drones over dense jungle in Central America to detect Maya ruins hidden beneath the canopy.

This thick canopy prevents a good connection between the base station and the drone, so he uses PPK instead of RTK corrections with his Reach base station to achieve high accuracy on his 3D models.

Emlid Reach RS2+ base station — *Reach RS2+ as a PPK base station for a DJI M300 drone equipped with*
*a Zenmuse L2 LiDAR*

“I use the Reach RS2+ as a base station and the Reach RS3 as a rover. The jungle is so dense that sometimes RTK doesn’t go far, but the base station just keeps recording. With the PPK and Emlid equipment, it’s easy,” says Mark.

Mark also uses his Emlid receivers for excavating artifacts. His team sets up a highly accurate point using the OPUS post-processing service and then builds a grid with strings and nails over the surface to be excavated. These points can be easily referenced years later, and the present datum can be tied back into for further measurements. That allows them to know where they have dug and what they have found.

GNSS in archaeology — *Subsurface topography of Maya pyramid sites*

Designing water storage systems

Nick Steiner works in water cycle restoration, using GIS tools to design landscape interventions that capture, move, and manage rainwater effectively. He relies heavily on QGIS for topographic analysis, calculating catchment areas, water flow paths, and pond placement based on rainfall patterns. Once the pre-analysis is complete, his team transitions to fieldwork, where they design and mark project elements directly in the landscape.

Reach RX in water cycle restoration — *Nick Steiner captures and designs landscape interventions with Reach RX*

With highly precise and easy-to-use Reach RX integrated with QGIS, Nick’s team now completes much of their design work on-site, greatly improving efficiency. Previously, relying on phone GPS meant working with an accuracy margin of several meters, which limited his design capabilities. GNSS integration significantly improved the data quality of Nick’s projects.

“Thanks to the Reach RX, we can design directly within the landscape,” says Nick.

GNSS benefits go beyond accuracy

High-precision GNSS not only improves spatial data quality but also streamlines GIS workflows and expands field capabilities:

Simplified field data collection: GNSS-integrated apps like QGIS and ArcGIS Field Maps let users collect accurate data on the go. So, no more guesswork or manual corrections.
Increased efficiency: What once required flags, pens, and paper now happens digitally and precisely with minimal equipment.
Flexibility and ease of use: With intuitive setup and compatibility with both open-source and proprietary GIS software, Emlid GNSS receivers can be used even by teams with no surveying experience.

Try Reach GNSS receivers for your GIS projects

From urban utilities mapping to remote archaeological digs, Emlid’s Reach GNSS receivers empower GIS professionals with centimeter-precise, reliable, and user-friendly solutions. If your work involves collecting geospatial data and accuracy is crucial, consider upgrading to GNSS with Reach RX or Reach RS3.