How much water are we using inside our homes?

Water wasters, your days are numbered.

Tuesday, state officials proposed new targets for saving water.

On the highest end of the spectrum, water districts using more than 165 gallons a person per day will have to cut back by 35 percent.

Districts using less, averaging 55 gallons per person per day or less, will only have to reduce use by 10 percent.

By some estimates, outdoor use accounts for half or more of the water consumed by residents in California.

But for those of us living in apartments with no lawn, 55 gallons a day per person may sound like plenty of water to spare.

"Sure, 55 sounds like a lot," said John Bock, who directs Cal State Fullerton’s Center for Sustainability. 

But Bock says even city slickers can run through gallons without thinking.

"The average shower is 17 gallons," he said. "The dishwasher takes about six gallons per load on an average dishwasher."

Hand washing dishes can be an even bigger drain since running the sink takes two gallons per minute. Ten minutes of dish washing can cost 20 gallons.

You also lose a gallon and a half with every toilet flush, and a load of laundry can cost eight more.

Then there's all the miscellaneous sink time we may not be thinking much about.

"Brushing your teeth, washing your hands... spending ten minutes a day doing those things, that’s 20 gallons right there."

It adds up.

Kelly Sanders with USC's Department of Environmental and Civil Engineering says one reason we may not have a good sense of our indoor usage is because we don't meter individual activities.

"We can't actually differentiate how much water you are using for your showers versus your bath versus you faucet," she said. "So it makes it kind of difficult to understand these things."

There have been some efforts to break down the numbers though, says Peter Gleick, president of the Pacific Institute in Oakland.

He says about 30 percent of our indoor water use goes to flushing the toilet, 20 percent goes to showers and baths, 15 percent is used to wash clothes, and the rest is lost to dish-washing, faucet use and leaks.

"Truth is our water use adds up and we sometimes don’t even know it," he said.

USC's Sanders says when it comes to curbing indoor use, a lot of the low hanging fruit has been picked thanks to low flush toilets and water saving shower faucets, which are now pretty common in newer homes.

Still, Gleick says it's worth it for residents to check their toilets and faucets to make sure they aren't running or leaking.

In Los Angeles, residents can take advantage of rebates from the city to purchase low-flow toilets, high-efficiency washing machines and other water-saving products. Mayor Eric Garcetti on Thursday brought attention to the city's money-saving, water-saving incentives in a new public engagement campaign aimed at getting residents to help L.A. reduce its overall water use.

For the state to really cut back it's water use, though, Sanders says saving in the home won't be enough.

"It's really going to come down decreasing outdoor landscaping, which is going to be the hardest thing to decrease," he said.

With state mandated conservation goals though, many communities may not have a choice about that.