Can I use the effect of a Stadium like Rough Seas, then play Delinquent to remove the Stadium, then play another Stadium of the same name as the original and use its effect too?
Yes, that is permissible.
Source: TPCi Rules Team (2016-02-25)

Relevant cards

Note: All applicable cards may not be listed below.
XY9_98
XY9_98a
XY9_98a
XY9_98b