The Jordan River had a lot more water than it has been having, and the path going through the tunnel under 126 South was flooded. I had to walk on rocks that are between the path and the bridge foundation. Those rocks are on a upward slope, and the river would have a hard time flooding clear to the foundation. The tunnel under 106 South wasn't flooded, because the path in the tunnel has a concrete wall bordering the river.
The water in the river is controlled by a pumping station on the north shore of Utah Lake, and it apparently put extra into the river to keep the lake from flooding. We've had a couple weeks of abnormally warm temperatures, and the heavy snow pack in the mountains is probably melting faster than normal.