When a tunnel is built, the portals are higher thus reducing the chance of massive high tides flooding it.
Nothing is safe proof. However, if a tunnel there was flooded, the swampy land that the main road is built on will also be flooded too, so even a bridge to a moat-like roadway wouldn't help.
When the weather calls for a hurricane and people are asked to leave, it is far BEFORE the hurricane gets here.
The bridge/tunnel should exit the Wilmington side at Shipyard Road for many reasons:
Shipyard road is already three lanes and can hold the traffic easier than Independence.
Shipyard has all the trucks there, and can go directly across the bridge heading west, vs still taking a lot of city streets.
Distance across the river is shorter there and would use a shorter bridge.
We really could just replace the existing bridge downtown with a beautiful bridge like in Charleston.
Make it four lanes each direction for future use.
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