STANDARD COLOR CODES:
Ground level: tan
Grades: yellow
2nd level: green
Industries:  dark gray or white
Roads: brown

TRACK COLOR CODES:
9", 3" straight: white
6" straight: gold
2-1/2", 1-1/4" straight: dark blue
2", 1" straight: blue-gray
1-1/2", 3/4" straight: pale blue

Rerailer: medium blue
Bumper: medium blue

15" curve, half-curve: lt gray
18" curve, 1/3-curve: dark gray
18" 1/2 curve: pale green
22" curve,  1/3-curve: gold
Flex track: yellow (see each plan's BOM for radius information)

Snap-switch RH turnout: orange
Snap-switch LH turnout: pink
#4 RH turnout: blue-gray
#4 LH turnout: dark magenta
#4 Wye turnout: olive green

30 deg crossing: yellow
45 deg crossing: medium green
60 deg crossing: pale blue
90 deg crossing: dark brown

Warren truss bridge: dark brown
Deck truss bridge: medium brown
Plate girder bridge: blue-gray

Suggested electrical block boundaries: red