The bumper storage in the new Airstreams has better drainage than my '76 did.
Think of your bumper storage compartment as the "mud room." A great place for dirty, greasy, stinky items. It should be well drained,
On my '76, I installed an under-belly-sewage-hose-holder. That freed up the bumper storage for my weight distribution bars. Some airstreamers stow their 30 amp power cord in the bumper in three great loops instead the more compact, harder to stow coil.
2019 Flying Cloud 27FB
2020 GMC Sierra 1500 Crew Cab 6.2L Max Tow
Four Corners Unit WBCCI #5783