Libs would go insane. DC stuff like a reflecting pool is very important to them.

Aesthetics of solids vs flowing liquids aside, resin just doesn’t hold up very well under constant UV light. I don’t want to know what it would cost just to tear it up, nevermind replace it when that happens. Unless there’s some super resin I dont know about.

Other considerations:

• a million particles would get trapped in the resin before it cures.
• resin heats as it cures which could do massive damage to the basin at such large volumes.
• that amount of resin would be a nightmare to mix/pour evenly and cure quality would be highly dependent on weather. You’d probably have to do it in layers, which just creates more opportunity for debris to get trapped inside.
• wear and tear. I bet you would have all sorts of people and wildlife walking around on it and scratching it up.
• stains from said people and wildlife.
• yellowing and clouding over time, which will make it not so reflective plus plastics in general are a bitch and a half to buff/polish

…honestly you’d be far better off filling it with polished concrete or stone. Just commit to the bit at that point. You can even dye it.

I’ve pivoted to recommending mercury

Pouring thousands of gallons of epoxy to simulate water would be incredibly American.