ID this type of farm BRIDGE, please

 

What is this bridge for, exactly?  Here it is, from both sides:

http://personal.morris.umn.edu/~webbrl/blog/SundeBridge1.jpg
http://personal.morris.umn.edu/~webbrl/blog/SundeBridge2.jpg

Some info:
1.  It's old (obviously).  Boards (for walking across) seem too rotted
to hold much weight.
2.  I don't think it's wide enough for a tractor to drive across, but
it's obviously not just for human foot traffic, right?
3.  The ditch of water beneath it is maybe 10-15 feet wide.  I think
it's a man-made tributary from the Chippewa River.  It seems to run
neatly along the boundaries of farm quarter sections in the area.  The
bridge seems to connect two farms across the water.

Was the water used for irrigation, do you think?  What role did the
bridge play?  Thanks if you can help (or direct me to another source).

 



Looks like a pulley bridge where only one side is opened up
(by pulling
one side up into the air) to let traffic (boats) through.

There's probably a hundred and one things that the water was
used
for but since it was made to open, the water was definitely
a pathway
to bigger waters.  Most likely dug wider and deeper by man
to help
accumudate irragation for the two farms.

Donna
in WA who is just guessing.....

 

On 05/25/2010 04:21 PM, MNRebecca wrote:

It's an interesting structure.
Would it be possible to get more pictures, possibly directly
down the bridge, from end to end?

 

On Tue, 25 May 2010 14:21:04 -0700, MNRebecca wrote:


Pipeline bridge?  

 

MNRebecca wrote:

That looks like a canal for transporting small barges... often they
would be spanned by variously configured Bascule bridges... used for
foot, cart, and livestock traffic.  The one you depicted is probably
no longer used.

http://en.wikipedia.org/wiki/Bascule_bridge