Is it permissible to take water from a pipe that passes in front of the house without the knowledge of the state, due to the difficulty of water availability and its high cost?

It is the right of the people that their rulers provide them with water, if that is within their means. If the rulers fall short in providing water or prevent it without a legitimate religious reason, then there is no objection to the people taking water to the extent of their need without the rulers' knowledge, as long as it does not harm others or themselves.