Elevation Maps

Seeing what rivers leave behind

Rivers reshape the land around them over centuries - carving new channels, abandoning old ones, leaving behind a hidden record of every path they've ever taken. A Relative Elevation Model, or REM, is a way of reading that record.

By recalculating terrain height relative to the river's own water surface instead of a distant reference point, an REM reveals features that are otherwise invisible: ancient meander scars, oxbow lakes, buried channels, and the layered terraces that tell the story of how a river has moved through its valley over thousands of years.

Standing on the shoulders of Daniel Coe

The technique was pioneered and popularized by cartographer Daniel Coe of the Washington Geological Survey, whose lidar-derived river maps - from the braided channels of British Columbia's Tulsequah River to the sweeping meander belt of the Lower Mississippi - showed the world that scientific elevation data could produce images as striking as any landscape painting. His work opened a new genre of cartographic art, one that sits at the intersection of geomorphology and fine art.

Lidar precision, sub-foot accuracy

Our Elevation Maps carry that tradition forward. We start with high-resolution Digital Elevation Models captured by lidar - laser pulses fired from aircraft that measure ground elevation to sub-foot accuracy. Multiple survey tiles are seamlessly merged and blended to create a continuous terrain surface free of seam lines.

That terrain is then processed through our REM pipeline: the river's centerline is traced, elevation values are sampled along its path and interpolated across the full floodplain, and the result is a surface where every pixel represents height above the river itself. Features hidden within inches of relief suddenly light up in vivid detail.

Color, light, and depth

The final REM is rendered with carefully tuned color ramps - deep tones pooling in the lowest channels, warm golds and whites rising across terraces and ridgelines - with hillshade overlays that give the terrain a sculptural, three-dimensional quality. Like all MapWorks products, the output is a print-ready poster with custom title, subtitle, coordinates, and tagline, exported at up to 600 DPI in SVG, PDF, or high-resolution raster.