if it helps:
Definition: [n] the occurrence of a water flow resulting from sudden rain or melting snow
[n] a sudden forceful flow
[n] (often followed by 'of') a large number or amount or extent; "a batch of letters"; "a deal of trouble"; "a lot of money"; "he made a mint on the stock market"; "it must have cost plenty"
Synonyms: batch, deal, flock, freshet, good deal, great deal, hatful, heap, lot, mass, mess, mickle, mint, muckle, peck, pile, plenty, pot, quite a little, raft, rush, sight, slew, stack, surge, tidy sum, upsurge, wad, whole lot, whole slew
perhaps the term "Häufung" meets the bill?