On the 1st day of Rosh Hashanna (if not Shabbat), customarily people go to a body of water for Tashlich. Does the water have to be there currently and must be a "natural" body of water? If so, what's the minimum size? For example, would any of these situations be considered fine for making Tashlich?
- a wadi or other dried up lake, stream, or river
- a small brook in a forest trail that has non-visible water but the leaves or moss is damp
- filling up a basin with water from a hose. How large must the basin be?
- turning on a fire hydrant in the street
- a puddle of rain in your driveway or in a pail outside your home
- snow or ice (it could happen!) on your lawn
- Does the water have to be liquid? What if you go to a frozen lake?
Kaf HacHaim (O.C. 583:30) mentions that in Yerushalayim, people said Tashlich at a well or pit even if there was no water in it. He states that the most important thing is the intention of ridding sins in the "upper ocean".
Based on this, it may be possible that the 1st & 2nd items in the list may be permissible, but I'm uncertain, if this can be inferred.