Aerial Photogrammetry for Land Surveying & Civil Engineering
Drone Land Surveying Services in Northern Virginia & DC
DeMarr Engineering’s aerial photogrammetry services are utilized for topographic mapping, corridor studies, site development, volumetric analysis, and construction planning where high‑resolution, survey‑grade data is required.
Aerial Platform
DeMarr Engineering utilizes a Wingtra fixed‑wing Unmanned Aerial System (UAS) to carry multiple payloads in support of photogrammetric surveying missions. Our primary camera payload is a Sony RX1R II full‑frame camera, capable of capturing hundreds to thousands of high‑resolution photographs across a project site.
Typical flight operations are conducted between 250 and 350 feet above ground level (AGL), depending on required resolution and site conditions.
The Sony RX1R II captures 42‑megapixel imagery using a 35‑mm full‑frame CMOS sensor. Under optimal conditions and following photogrammetric processing, DeMarr Engineering can generate a single orthomosaic with a ground sampling distance (GSD) as fine as 0.5 inches.
For example, a 50‑acre project site processed at 0.5‑inch GSD results in imagery where each pixel represents approximately 0.5 inches on the ground, allowing for precise visualization, measurement, and analysis.
In addition to camera performance, the Wingtra UAS is equipped with RTK/PPK GNSS technology, enabling centimeter‑level positioning accuracy when integrated with survey control.
Selecting a Geospatial Data Firm
Every DeMarr Engineering photogrammetry project is georeferenced to survey control established by a Licensed Land Surveyor. DeMarr Engineering is more than just a UAS “drone services” firm collecting raw imagery; we are a licensed Land Surveying and Civil Engineering firm with in‑house Licensed Surveyors and Licensed Professional Engineers who supervise, process, analyze, and certify the data.
When selecting a firm to provide UAS‑based geospatial data, the first and most important question a client should ask is:
Is your firm licensed to perform photogrammetric surveys?
Under the Virginia Administrative Code, photogrammetric surveys and similar remote sensing technologies must be performed under the direct control and supervision of a licensed land surveyor or licensed surveyor photogrammetrist.
18VAC10-20-392. Photogrammetric surveys or similar remote sensing technology.
Clients should also ask:
Is the data produced under the supervision of, and backed by, the certification of a Licensed Professional?
The Virginia Administrative Code requires a certification statement on all topographic surveys, plats, maps, and digital geospatial data, including associated metadata.
DeMarr Engineering is licensed to control and supervise photogrammetric surveys and to certify resulting geospatial data for use in land surveying and civil engineering work products.
Final Deliverables
Following data acquisition, DeMarr Engineering processes all imagery in‑house using secure, on‑premise computing systems. Hundreds to thousands of individual photographs are processed into a single, georeferenced orthomosaic dataset suitable for professional surveying and engineering use.
- Scaled PDF plots (24”×36” or 36”×48”)
- Printed plan sets produced through local print shops on bond or presentation‑grade paper
- GeoTIFF (TIF) orthomosaic imagery
- KMZ files compatible with Google Earth Pro
- Cloud‑hosted datasets for viewing and measurement
Results & Professional Oversight
By combining high‑resolution aerial imagery, survey‑grade positioning, and licensed professional oversight, DeMarr Engineering delivers photogrammetric survey products that meet regulatory standards and can be confidently utilized for land surveying, engineering design, and construction planning.
Partner with DeMarr Engineering
For large project sites in Loudoun County, Fauquier County, and the surrounding Northern Virginia region, DeMarr Engineering provides survey‑grade aerial photogrammetry services backed by licensed professional oversight and proven workflows. We support public agencies, developers, and project teams that require high‑resolution imagery, verified control, and defensible geospatial data suitable for land surveying, engineering design, and construction planning.
DeMarr Engineering’s land surveying services are most effective when integrated with our in‑house civil engineering capabilities. This unified approach allows survey data to be evaluated, interpreted, and applied directly to engineering design and construction decisions, improving coordination, reducing ambiguity, and supporting efficient project delivery.
From initial project planning through final deliverables, DeMarr Engineering works collaboratively with clients to ensure data accuracy, regulatory compliance, and reliable results at scale. Contact DeMarr Engineering to discuss how our aerial photogrammetry and geospatial surveying services can support your next large‑scale project in Northern Virginia.