Cool premise for a strategy game,
i like how you went for a sort of "Patlabor" approach where mechas are not only just war machines but also used for other tasks such as construction and in your game's case firefighting.
I like the different capabilities of the 3 units, even if it's a bit hard at first to understand how to properly secure the different cities from the fires spreading each turn.
I had one issue, i couldn't figure out how to refill the water tank of the firehose mecha, i could refill the chopper though, so i don't know what i missed :/
Other than that it's a neat entry :)