Slope & ContourMeasure the gap between contours on your survey and get the real slope in %, degrees and 1 in n, the true length along the ground, and how far apart contours must be for any slope you want to design.

SheetT-49
MethodRise ÷ run
Unitsm, mm, %
By@smart_tools_every_week
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Measure on the print, square to the contours. "Contours crossed" is how many intervals the measured line climbs (1 = between two neighbouring contours).

Target slope gives the contour spacing you must draw on the grading plan. 8.33% = 1 in 12, the ADA 2010 ramp limit.

Slope–
Angle–
Gradient–
Ground run–

Contour plan

Section true proportion

% vs degrees 100% = 45°

Slope table

SlopeAngle1 in nContour gap on mapOn groundNote