This is the 15296th most frequent German word.
unnötige
Unnecessary.
Here, the word 'unnötige' qualifies 'Ausgabe' (expense), describing it as not needed.
Der Kauf dieses Geräts war eine unnötige Ausgabe.
Buying this device was an unnecessary expense.
The word 'unnötige' is used to describe 'Sorgen' (worries), indicating they are not warranted or essential.
Wir sollten uns unnötige Sorgen um die Zukunft ersparen.
We should spare ourselves unnecessary worries about the future.
In this context, 'unnötige' characterizes 'Baustelle' (construction site), implying it could have been avoided.