I need to know how much this pipe weighs per foot. I googled for about
an hour with no luck.

12" galvanized corrugated 16 gauge pipe --typically used for culverts

--Zeb

Well, I don't know about actual standard weights, but i can estimate it
if you like:

cross-sectional area of 12" OD x 0.06" wall pipe = 2.25 sq. inches
wall volume for 12" of length = 2.25 x 12 = 27.00 cu.inch
density of steel = 0.283 lb/cu.inch
weight of 12" of straight pipe = 27 x 0.283 = 7.64 lbs

The corrugations will effectively increase the volume without
increasing the length. Here's a site I found with some dimensions for
the corrugations:

http://www.southeastculvert.com/standard%20pipe.htm

2.66" pitch x 1/2" depth of corrugations means that every 1.33" of
linear pipe uses approximately 1.42 linear inches of material. This
gives a ratio of 1.07 so the overall weight per foot is 7.64 x 1.07 =
8.16 lbs/foot.

That's how I would figure it anyway.

Take a bathroom scale to the supplier and weigh a section. Then divide
by the length in feet.

Stretch