I like our system of completely grade separated bike paths around here, except from one minor problem.
This is the Guadalupe River Trail under Montague Expressway in San Jose this beautiful, sunny morning after a few days of rain. This undercrossing is passable for now, though it’s a little bit muddy. Last Friday the water here was a good three to four feet higher than this. I haven’t tried the other undercrossings near the airport, but historically they’re covered in a foot of mud after a good deluge.
In the U.S., grade separation is accomplished by running levee trails like this one underneath the highway bridge over a river. The result: trail closed in heavy rains.
My colleague Naoto sends the above photo from the San Tomas Aquino Trail in Santa Clara, where they closed the gates.
Lady Fleur (who rides this trail too) writes on flooded trails.