Leave the mast tied to the bridge!
When you come back from sailing have someone on the bridge reach out with a pole to grab the mast at/under the speaders. Use quick release toggles on the rigging
to release it from the boat.
Then slide the mast over to one side of the bridge so other boats will not hit it and cover it with half a plastic light standard. Works best if the light standard covering matches others in the area.
Get fancy and have the speaders fold down and no one will know. Spot the mast in this photo:
Even the radar
looks like it belongs!