给水

Note 给 here is jǐ (3rd tone, 'supply / provide'), NOT gěi (3rd tone, 'give'). Same character, different reading and register — gěi is colloquial 'give', jǐ is formal/technical 'supply'. Compare 供给 (gōngjǐ, supply) and 自给自足 (zìjǐ zìzú, self-sufficient).

Technical / engineering vocabulary — used in city utilities (给水管 water-supply pipe), boilers, fire systems. In casual speech you'd just say 供水 (gōngshuǐ).