Higher water bills are likely coming next year in Nashville. And as part of the change, homeowners will have more reason to conserve water than in the past.

For the first time, Metro Water wants to distinguish between water needed for essential living, versus water put to more optional uses. Metro Water Director Scott Potter says a study found that Nashvillians need about 60 gallons per day (which is somewhat below the national average).

“So beyond that, when people start using the water for a different purpose — and let’s say they’re irrigating their yard — that water, in my opinion, has a little bit of a premium associated with it,” Potter told the Metro Council in a special meeting this week.

It’s always been the case that the more water you use, the more you pay — as that meter runs. But what’s new is Metro Water wants to create four different tiers of homeowners, based on usage.

For households that use the least — up to roughly 50 gallons per day — water bills would barely increase at all. But if you reach the second tier, the rate is higher, and higher still at the third and then the fourth tiers.

The agency hopes this encourages water conservation — because there’s an even bigger price difference if you can stay at a lower tier. Metro Water also says this could conserve electricity, since it pays a lot more to run its pumping stations when demand on the system calls for a few million extra gallons of water.

The Metro Council still must vote on the water rate increase, and that’s scheduled to happen before year’s end.

Full details about the proposal, including a bill calculator, are online here.