Issues with incorrect values for contour map in QGIS

Hello. So I export the the shapefiles from DD into QGIS I can see all the lines fine and get values attached to the lines, but they are not the correct elevation. In DD when I draw a line to measure the elevation, its 100% correct, but once in QGIS it’s a much smaller value. So I’ve made sure that all my settings on both platforms are in feet.

I don’t think it’s an EPSG issue, I’ve tried both desktop and web and made sure that QGIS was updated aswell. I don’t know what I’m doing wrong. Any ideas?

State plane projections are X, Y so that doesn’t have anything to do with elevations. Does the map measure horizontally correctly in QGIS? It could be a scaling issue. How much smaller are the values?

If the values of the lines imported into QGIS are approximately 3.2 times lower, I have a guess.

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Yes! That sounds about right. So what’s up?

Hi Bryce, that is the conversion factor for meters to feet. So it appears the contours are coming into QGIS in meters. You should be able to convert them in QGIS.

3.2808 = 39.37/12 for meters to feet

Thanks @Dave for cleaning this one up!

Hi @Bryce1410,

The reason as to why you are obtaining the elevation in meters when importing the contour files into QGIS, is because you are exporting the map using map projections (EPSG codes) that use the metric system. Both, the Desktop (WGS84 with EPSG 4326) and the Web (Web Mercator with EPSG 3857) use elevation in meters.

If you are looking to get the results in imperial units, I recommend you to Export your data in other projection systems. We have a drop-down option within our Business and Enterprise plans that allows you to choose different map projections, especially if you are using a State Plane coordinate system and need to get the elevation in feet.

I hope you find this information helpful. Happy mapping!

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