Ernest,
I was there 95-97, come the summer the beaches would be packed, the apartments fully booked, but the water still tasted like cr@p, the toilets stank and the streets littered with dog turds.
Ostend could be considered upmarket ... if they knocked it down and started over again and/or relocate it outside of Belgium.
I think the mega incident occurred during the 98 airshow which resulted in air shows being banned in Belgium.