Under the Ground Watering System
This page is the CodyCross answer for the clue below from Small World, Group 697, Puzzle 4 (Poison Dart Frog).
Question is: Under the Ground Watering System
and the answer is: IRRIGATE
Word Meaning:
IRRIGATE — (transitive) To supply (farmland) with water, by building ditches, pipes, etc.
Definitions from Wiktionary.