What is the "average" difference in elevation from the middle of an NFL football field to the sidelines.

Answer 1

18" from center crown of the field contouring to the sideline for drainage. I've been on football fields and it's very apparent that the center is higher than the sideline height.

Contouring the Subgrade
In order to remove excess water from the playing field, it is absolutely essential that an 18-inch crown be established down the center of the field, along with necessary drainage down both sidelines (see Figure 1). In order to remove excess water from the sidelines, corregated plastic drainage lines with pea gravel backfill or catch basins should be constructed. The drainage lines should be placed within slight swales running lateral to the sidelines.
With a properly constructed 18-inch crown, a tile drainage system under the entire field is not necessary unless underground seepage is a problem. Surface compaction usually renders a general tile system ineffective. (Since the high center crown of football fields makes side shots in soccer difficult, it is not advisable to use the same field for both sports. Soccer fields should not have more than a one percent grade from the center of the field to the edges.)

Answer 2

Penn State's "beaver stadium" has a 25cm crown
Princton's stadium has a 9" crown
University of Tenn has a 12" crown
Duke hase a 12" crown
UW Husky Stadium has an 18" crown...

Some schools have crowns over 24"...

but I can't seem to find any regulations for the height of a fields crown in the NFL... but since the seahawks played thier full season in Husky Stadium a few years back the NFL has to allow at least 18"

Answer 3

Well the middle of the field might be 1 or 2 inches higher than the sidelines to allow for rain run-off.

Answer 4

should be 0