# How large a hole will rain fill with source blocks?

From MineCraftWiki.net:

(...) and possibly fill up small holes up with water source blocks.

Does anyone have any information about the dynamics of this functionality? Specifically I'm interested in answers to the following questions:

1. What is the maximum width and length of a hole that can be filled by rain?
2. If a hole is 1m wide by 1m long by 2m deep with a source block filling the lower empty space, will rain fill the upper empty space on top of the existing source block?
3. If the answer to #2 is "yes", what is the maximum depth of a hole that can be filled in that manner?
• Notch mentioned this on twitter, but only as a passing thought. I'm not convinced it was actually implemented. Apr 19, 2011 at 19:08
• It wasn't. 5char Apr 19, 2011 at 19:43
• First person to post evidence that it wasn't implemented in 1.5 gets the check-mark. Apr 19, 2011 at 20:48
• @JonnyP what, you mean like uploading a video observing a 1x1x1 hole that doesn't get filled for X minutes? Apr 21, 2011 at 6:21
• Gaming.SE is my number 1 source for Minecraft update news, mythical or not. About 3 Q's since 1.5 I've read the description, said "What??" and spent an hour messing around with a new feature in game. Apr 21, 2011 at 16:37

I had a rain storm which lasted all night and for half the next day, no holes were filled with water of any size. I had a small moat I had dug one block deep, but not yet filled with water, as well as a few one block deep holes scattered around. None of them become filled with water.

I don't think it is implemented.

• Seems proof enough. Apr 21, 2011 at 16:17
• Has this changed in a couple years? Jan 2, 2015 at 18:44

Something that can (partially) fill with water during a rainstorm is a cauldron.

A cauldron has approximately a 15.5% chance of being filled with at least one level of water when exposed to one session of rainfall (Tested with 1000 cauldrons during a regular 15 minute rainfall session).

I don't think that rain can fill holes in the ground, so you were misinformed.
Instead, it can fill cauldrons, but the water inside of them cannot interact with the world properly. (e.g. breaking it won't yield water, endermen won't take damage in them, etc.)