I'm not sure how the housing association works, especially in the US, but is there a way to contact somebody (human that is, not a computer form ;) ) to let them know about the impossibility involved here? Perhaps the system is stuck on something automatic and they need to make an adjustment for this drought period. Best of luck, OP! Hope you don't get fined whatever you do, and if you do get fined, I hope that you can contest it :)

Are you from California?

I bet the city doesn't take precedence a hoa can lien your property which is much worse then what the city can do. Just pint your grass green like everyone one else

Either way, you're out $150 dollars. Maybe they're conspiring!

Easy. Hook up your grey water to irrigate your lawn. So long as you aren't dumping toxic chemicals down your kitchen sink it'll be fine. Bam, your lawn will be watered every time you shower. Also, soaps have nitrates which practically makes them fertilizer.

Call someone and complain.

Just water it anyway. You have to pay anyways

your deserve it living in a place where they can tell you what you have to do to your house

sounds like good ole California

Tell HOA they will need to pay for your 150 bill from the city before you water your lawn. This why I would never buy a property that has HOA. You have to spend hundreds of dollars a month so someone else can you what you can and cannot do on your property.