Key takeaways
- An Alberta assessment complaint argues about value on a valuation date. Imagery is evidence about physical fact, not about value, so it supports an argument an agent or appraiser makes rather than making one itself.
- The date is the whole problem. Market value assessments are prepared against a legislated valuation date, with the property's physical condition taken as of a separate condition date. A capture flown this month is not evidence of either unless the site has not changed.
- What imagery does establish well: how much of a parcel is actually usable, what is built and what is not, surface condition, access, yard and laydown extent, storage, drainage problems and visible deterioration.
- A board will not take a value opinion, a comparable selection, a boundary determination or an unreferenced measurement from a photograph. A measurement needs a georeferenced product with a stated method.
- The strongest use is a baseline capture flown before anything is in dispute. Owners of large industrial, commercial and acreage parcels who fly annually already have the evidence for whatever year becomes contentious.
- Complaint deadlines are short and are printed on the assessment notice, and boards run on disclosure timetables. Imagery commissioned after the disclosure deadline is usually too late to file, whatever it shows.
- Cheapest route to the evidence: if the condition in dispute is still visible on the ground, fly it now and argue continuity. If it is not, the archive you did not build is the gap.
Assessment complaints in Alberta turn on two questions. Is the assessment at market value, and has the property been treated the same way as comparable properties. Both are value arguments, and both rest on physical facts about the parcel that somebody has to establish. That second part is where aerial capture belongs, and it is the part most often argued from a handful of phone photos and a verbal description.
This is written for owners and managers of larger parcels, because that is where the arithmetic works: industrial yards, aggregate operations, commercial sites with large laydown or parking areas, acreages, and anything where a meaningful fraction of the land is unusable for a reason you can see from the air.
How the dates work, and why this is the first thing to settle
Alberta market value assessments are prepared against a legislated valuation date, which is the July 1 preceding the tax year, with the property's physical condition taken as of the following December 31. That means two separate dates matter, and neither of them is today.
The practical consequences:
- A capture flown in the spring is not direct evidence of the previous December's condition. It is evidence of a current condition from which continuity can sometimes be argued, which is a weaker but often sufficient position.
- If something changed between the condition date and the flight, say a building came down or a yard got paved, the imagery can actively hurt the argument unless the change is disclosed and dated.
- Imagery captured before the condition date, for any other reason, is frequently the most useful evidence in the file. This is the strongest argument for a routine annual capture on a large parcel, which we have written about in how often to re-fly a site.
Confirm the dates and the complaint deadline on your own assessment notice. The deadline is printed on it, it is short, and it is not extended because the imagery was not ready.
What imagery actually evidences
Keep the claim narrow and the imagery is hard to argue with.
- How much of the parcel is usable. Slope, wetland, a ravine, a right of way, a drainage course, bush that was never cleared. On a large parcel assessed as if it were uniformly developable, the unusable fraction is the argument, and it is measurable from the air.
- What is built and what is not. Building footprints, whether an improvement shown on the assessment record still exists, additions that were never built, a demolished structure still on the roll.
- Surface and site condition. Pavement breaking up, a gravel yard rather than a paved one, standing water, an unimproved access. Condition is a legitimate valuation input and it is visible.
- Yard, laydown and storage extent. Where an assessment rests on how much of the site is in productive use, imagery measures it rather than estimating it.
- Access and functional obsolescence you can see. A single awkward approach, a site cut by a rail spur or a ditch, buildings laid out so trucks cannot circulate.
- Change over time. Two captures a year apart are a stronger exhibit than one, because they establish both condition and the fact that it was not a one day anomaly.
What an assessment review board will not take from it
Boards are generous about accepting evidence and specific about what weight it carries. Imagery will not carry:
- A value conclusion. Nothing in a photograph says what a property is worth. That is an agent's or an appraiser's argument, and the imagery is an input to it.
- A comparables argument. Flying a neighbour's property to show it is treated differently is not a route anybody should take. Equity arguments are built from assessment records, not from imagery of somebody else's land, and overflying a third party's property for the purpose raises consent and privacy issues of its own.
- A boundary. Where the line is, and therefore how large the parcel legally is, comes from a registered plan and an Alberta Land Surveyor.
- A measurement with no method. A dimension scaled off an unreferenced photo is worth very little. A dimension taken from a georeferenced orthomosaic with the ground sample distance, control and expected accuracy stated is a different exhibit.
- Anything below grade or structural. Foundation condition, contamination, structural adequacy. None of it is an aerial finding.
Making the capture defensible rather than decorative
The documentation requirements here are the same as any other dated evidentiary capture, which we set out in when aerial imagery holds up as evidence. For an assessment file specifically:
- Date and time stamped originals, unedited, retained and available. The deliverable can be annotated. The originals must exist unannotated.
- A stated coordinate system and a georeferenced product, so any area or distance in the exhibit is reproducible by the other side.
- A methodology note: aircraft, sensor, altitude, ground sample distance, control used, software, and the accuracy expected. One page.
- No enhancement beyond what is disclosed. Colour balance is fine and should be mentioned. Anything that changes what a viewer concludes is a problem.
- A pilot and authorisation record, because an exhibit produced by a flight that should not have happened invites a question nobody wants.
Where this actually pays, and where it does not
It pays where the disputed amount is large and the physical fact is clear. A large industrial parcel assessed as fully usable when a third of it is a drainage course. A commercial site whose assessment assumes paving that does not exist. An acreage carrying an improvement that was removed three years ago. In each case the capture is a small fraction of one year's tax difference, and the difference usually persists across years.
It does not pay on a small residential property, where the disputed amount rarely justifies any professional cost, and it does not pay where the argument is purely about market evidence and comparables. If your agent tells you the file turns on comparables, imagery is not the gap.
The timeline, which is tighter than people expect
An assessment complaint runs on a fixed sequence: the notice, a short complaint window, a disclosure schedule where both sides exchange evidence, then the hearing. Evidence filed late is frequently not admitted, which means the useful question is not whether imagery would help but whether it can exist before the disclosure deadline.
That window includes weather. A capture needs a flyable day, and in an Alberta spring that is not every day. Build slack in, and if the complaint window is already open when you start thinking about this, treat the flight as urgent rather than as something to schedule around a convenient site visit.
The baseline nobody has
The pattern we see on the evidentiary side of this work, whether it is an assessment complaint, a claim or a regulatory file, is that the capture people need is the one from before the dispute. It is also the cheap one, because nothing is urgent and the flight can wait for good conditions.
For an owner with a large parcel and a history of assessment disagreements, one capture a year, flown in the same window with the same parameters, produces an archive that answers the condition question for whichever year becomes contentious. That is the same logic as capture for a lender, an auditor or a board, and the archive serves all of those readers at once rather than one.