I don't know where you live and what type of well you have, but you should be better connected to the official water supply while using the water from the well additionally. Because of climate change (less rain, more heat) the earth will get drier, so the groundwater level will fall and you might have no water at all in your well during low-precipitation summer months. I wouldn't even count on a nearby lake as main water source with regard to the future.
Something like that could also work great as an addition (you can harvest pretty large quantities of rainwater), but you should go the official way too. Better safe than sorry.