How to measure stockpile inventory

Measurement methods from the good to the bad to the ugly.

As we have discussed in other articles, stockpile measurements help companies measure their inventory turnover ratios, measure efficiency of assets, track expenses and revenue, and much more. Companies have been measuring stockpiles for centuries. We will look at some of the more recent methods companies use to measure stockpiles. We are big champions of using a combination of surveyed ground control points and drones to ultimately collect data to measure piles. 

how to measure stockpile volumes

The ugly Measuring using GPS Receivers

A worker climbs a 40 foot pile of aggregate to the top, taking half a dozen points around the slopes of the pile. It’s hot out. The aggregate is loose. The data is sparse. This is a dangerous, inaccurate, and highly inefficient method to measure stockpiles. To give you an idea of just how bad this method is at collecting accurate data, lets look at one of our customers.

We did an initial survey for a national sugar manufacturer in central Florida. Our data came back with tenth of a foot tolerances measured to our ground control points set with RTK GPS.

Our client was surprises to find that the numbers his employee was getting with RTK GPS on a loader driven on the pile was a whole 33% off of the actual number. Upon comparing contour maps and examining our control, we were able to verify our data as the more accurate set. 

The Bad Unlicensed drone surveying

Drone Surveying without a license in Florida

Hiring a drone company or big national stockpile measurement company may seem more cost effective. However, when complications occur a company that hires unlicensed surveyors in the state of Florida have very few protections and could even end up in a law suit.

According to chapter 472 of the Florida Statues, surveying includes a number of practices many drone companies would rather not tell you. According to 472.005(3) ‘”surveyor and mapper” includes the term “professional surveyor and mapper” and means a person who is registered to engage in the practice of surveying and mapping under ss. 472.001-472.037. For the purposes of this statute, a surveyor and mapper means a person who determines and displays the facts of size, shape, topography, tidal datum planes, legal or geodetic location or relation, and orientation of improved or unimproved real property through direct measurement or from certifiable measurement through accepted photogrammetric procedures.’

We have been surveying stockpiles since 2017 legally, with a license for both our drone operations and our surveying operations. We are insured as well. In the years since our stockpile operations began, we have had a handful of times where things go wrong. This is where licensed surveying becomes highly valuable. 

Volume Calculation of Stockpile
This photo shows a stockpile of industrial slag at a port in Florida. The stockpile measurement for this industrial material was performed by Florida Aerial Survey Technologies

The Good Drone Surveying, the legal way

Why drone surveying benefits from licensed surveying. 

Hiring a licensed surveying company to measure and calculate stockpile volumes pays off. This is especially true when things go a bit wrong. Companies that do not use ground control have little ability to verify the data they get. Some programs can get it right 90% of the time without ground control, but without ground control it is all black box technology.

What we mean by this is the inputs get fed into a program, they come out, the company assumes they are correct, and has no real way to verify the data. Many of the companies that operate this way arent legally allowed under the Florida Statues to give you the information that should be included to verify the results of the data. A licensed survey company will have ground truthing and will be able to verify their results and work on any tolerances that are out of spec.

Why we are passionate about stockpile reports

Aggregate, fill, and roadworks companies’ lifeblood is their stockpiles. Stockpiles allow them to store the material they sell. Knowing how much material they have allows them to forecast, borrow, and ensure they have inventory for large projects.

We are passionate about providing excellent stockpile data to our clients, allowing them to focus on generating revenue with the assets and inventory they have on site. 

Stockpile used for site work in Florida
A contractor uses a stockpile measured by Florida Aerial Survey Technologies to

Scheduling a survey

We would love to help your company measure your stockpiles. We have decades of experience in surveying and construction as well as a long track record of accurately producing stockpile calculations. 

To schedule a survey contact us by using the button below.