A mod that adds realistic erosion and degradation of rocks.
No natural material is safe for weather. Rocks will erode to cobble and gravel, sand, clay and eventually slide down steep slopes in mud flows. Water makes erosion go even faster - rivers can carve large canyons if you're not careful.
Its eating the shore
It makes containing (with minerals wood still works) water more challenging. The sand in the coast begins disappearing and the dirt on the bottom of the river/lake/ocean turns to sand .I dug a downhill one block canal and after a while the water broke a block and spilled all over the hill, another time it plugged itself with a dirt block.