It is hard to grasp how large this structure is. It is also hard to find any kind of vantage point to take it all in given the trees, the levees, and the chemical plants on either side of the river. Notice also the interesting color of the bridge. It is not one of the standard silver, grey, or black bridge colors. The bridge was originally painted blue. But dust from an aluminum plant kept coating the bridge with aluminum-oxide. Finally, the state gave up trying to keep the bridge blue, and went with the orange color of the dust.
The Long bridge marks the spot where ocean-going ships can no longer travel up the Mississippi River. The navigation channel is at least 49 feet deep below the Long bridge, and often deeper than 200 feet. That is unique for a major river. While most rivers get wider, the Mississippi stays about the same width, but gets deeper. There are places in the Mississippi where the river bottom is below sea level as far inland as the border with the state of Mississippi. Above the Long bridge, the river channel is maintained at 12 feet, where it eventually drops to a 9 foot navigation channel that is maintained all the way to the Port of Minneapolis in Minnesota.
