This is the 7324th most frequent Japanese word.
事足りる
"To be sufficient" or "to meet the needs."
事足りる is used to express sufficiency or adequacy in the given context of preparation.
この資料があれば会議の準備には事足りる。
With these materials, preparations for the meeting will suffice.
事足りる is utilized here to denote that simple tools are adequate for the situation.
簡単な道具で事足りるので、高価なものは必要ない。
Simple tools will suffice, so expensive ones are not necessary.
事足りる conveys the meaning that water alone is sufficient as a drink in this context.