"A large parade of thousands of cars resulted in several accidents..."
So what...Cars get into accidents, boats sink.
Here’s an idea for an invention.
A drain plug that is opened by manually pulling on a ring.
When the ring is released, the plug closes.
Like a pressure bleed on a compressor.
Are you good at machining?
If you come up with the product, remember me when the profits come rolling in.
8^)