I live in Bulgaria where water is also generally safe to drink. However, the quality varies and sometimes a lot of chlorine is added to it. Also, there are areas here that go without tap-water some parts of the year. Luckily, there are many springs here so it's usually possible to find reasonably good water.
Still, because water is such an essential part ...
I was looking into this question for a project at work and found some research studies addressing water savings from automated faucets.
Automated faucets result in increased water and energy usage, based on several real-world studies
Increased water usage
Hills, Birks, and McKenzie, 2002. "The Millennium Dome 'Watercycle' experiment: to evaluate water ...
One option that would allow you to forgo filter disposal altogether, as well as provide you with purified water, would be to use a water distillation unit.
These are available in benchtop models such as this example