The Seafaring mod aims to add more substance to bodies of water in Minecraft. The sea floor now has a few new resources you can collect like rocks and pebbles but also salt piles. These can be converted to salt to make salted fish and meat.
With compressed sponges you can soak up a much larger body of water for easier clearing. You can then dry the soaked sponges out for re-use by putting them in a furnace.