Drone Program

Overview

In 2025, I became interested in the application of drones to GIS. The ability to collect near-real-time, high-resolution aerial imagery is an invaluable tool for a municipal engineering department - it allows stakeholders to monitor site development at every stage, enables accurate digitization of visible assets like manholes and fire hydrants, and provides a way to build accurate 3D models that preserve a "digital twin" of a real-world scene.

Operating a drone commercially on behalf of a government agency or company requires a remote pilot to hold an FAA Part 107 certification. In the fall of 2025, I enrolled in the sUAS Drone Certificate program at Bridgewater State University to build my understanding of drone operations, gain hands-on flight experience, and prepare for the Part 107 exam. I completed the program in the spring of 2026, earned my Part 107 certification, and began developing the framework for a drone program on behalf of the Town of Braintree Engineering Department.

Later that spring, the Town purchased a DJI Matrice 4E - an RTK-enabled, survey-grade mapping drone built for high-accuracy GIS work and aerial mapping. Massachusetts operates a statewide Real-Time Kinematic (RTK) network, MaCORS, made up of base stations that stream real-time NTRIP corrections to RTK-capable survey devices like the M4E. This gives the drone sub-centimeter positional accuracy in ideal conditions (in practice, I typically see around 0.6" horizontal accuracy reported through ArcGIS Field Maps) enabling precise georeferencing of the captured aerial imagery.

Workflows and Use Cases

Since acquiring the drone, I've used it to produce 2D orthomosaics and 3D models of sites throughout Braintree. Imagery is processed in DJI Terra, and turnaround time depends on the
scale and product. 2D orthomosaics process relatively quickly, while 3D models typically take overnight to reconstruct. Once Terra processing is complete, I bring the 2D or 3D product into ArcGIS Pro, clip to an area of interest if needed, project to Web Mercator, and publish to ArcGIS Online for sharing with others.

One recurring use is flying over streets ahead of paving projects to document pre-paving conditions. I've also flown over streets following infrastructure work (lead service line renewals, water/sewer main replacements) to capture the locations of trenches that are still visible once they've been asphalted over. This helps digitize the true locations of mains and services on our GIS utility layers.

Site development monitoring is another key use case. I've flown over development projects in Braintree before, during, and after construction, producing 2D orthomosaics and 3D models that I share with the rest of the organization through ArcGIS Online. This lets stakeholders visualize progress and measure volumes and areas to verify reported figures, informs meeting discussions, and gives people visibility into a site without requiring an in-person visit.

Standard Operating Procedures

At the moment this is a solo venture, but these procedures are intended to be scalable to potential future remote pilots who fly on behalf of Braintree Engineering. The file structure, mission report template, and data maintenance standards are all easy to copy from one user's machine to another.

File Structure

I maintain a specific file structure for drone operations.

Pre-Flight Checklist

Before every flight, I refer to a pre-flight checklist I put together based on the standards specified in FAA Part 107 documentation. Copies of this checklist are printed and stored in the drone case for convenient field access.

Mission Report

After every mission, I fill out a mission report titled with a date/time stamp and project description. The report is generated from a standard template with entry fields for date/time, location, mission summary, pilot name, Part 107 certification number, weather, cloud cover, LAANC number (if applicable), authorized and flown altitudes, data storage location for the project, and general comments. This creates a consistent, auditable record of every flight regardless of who flew it.

Data Maintenance Standards

Due to FOIA requirements, drone data must be retained for 7 years. Drone data (images, 4K video) can quickly take up significant disk space, so I added a 4TB SSD to my laptop as a dedicated GIS and drone data drive, and offload all data to a mission folder on this drive after each flight. Once offloaded, I make a second copy to a high-capacity external archive drive for redundancy.

LAANC Approval

Since the northern part of Braintree lies within controlled airspace, LAANC approval is required before flying in that area. A maximum altitude of 300 feet is permitted there (compared to 400 feet in uncontrolled airspace), and approval can be obtained in real time through a LAANC-enabled app such as Aloft Air Control. Once a LAANC approval number is received, it's recorded in the mission report for that mission.