Bodies of water and the definite article

Hello, all.

I'm hoping to find some kind of rule here.

(non-flowing bodies of water, relatively speaking)

The Pacific Ocean, the Atlantic Ocean, the Indian Ocean...

but

Puget Sound, Raritan Bay, Crescent Lake, Trout Pond...

(flowing bodies of water)

The Mississippi River, the Hudson River, the River Shannon...

but

Bull Creek, Elk Creek...

when it comes to man-made ditches/canals,

Meeker Ditch, the Parkland Ditch, the Panama Canal...

So, ocean names require "the," but bays, sounds, lakes and ponds don't. River names require "the," but creeks don't. For man-made ditches and canals, you just have to know whether "the" is part of their proper names.

Am I correct?

Thanks.