Israel is in a very weird position, being expected to provide supplies to sustain their opponents.
I can see that it seems counterintuitive, but it's a norm and law of war - applying to all partie at war, not just Israel - that civilian populations must be allowed the bare necessities of life.
Water is one of them. As for fuel, other countries can pay, but Israel (and if it were the UK, Peru etc...) needs to allow it through. Hospitals are protected by law and convention, as are water treatment plants.
As there is no running water, let alone sewage works, I'm certain that we're soon going to to see cholera and typhoid, which is entirely avoidable. Tony Blair, among others, is likely to have committed a war crime, by having the RAF bomb Iraqi water treatment infrastructure and then refusing even UN inspected replacement parts.