If you’re trying to save money, which bathing option uses more water? How can you tell?
Comparing a shower to a bath is like comparing apples to oranges. That’s because you measure showers by duration (how long the water is running while you’re in the shower), but you measure baths by the amount of water it takes to fill up the bathtub (regardless of the time).
As a general rule, taking a bath uses more water. However, these are some factors to consider when trying to determine which method is more (or less) water efficient.
How big is your bathtub? According to data from the USGS Water Science School, the average person needs 36 gallons of water to fill the bathtub. However, a larger than average tub will need more water.
Another factor to consider is how much water you’re running in the bathtub. It takes more water to actually fill to capacity, compared to filling it halfway or three-quarters of the way full.
How long are your showers? Are you singing one song as you shower or a compilation of greatest hits? The longer you remain in the shower, the more water you’re using.
Also, leaving the water running while you’re lathering your hair and/or shaving causes you to consume more. Think about it: if you wash your hair in the bathroom sink, you would cut the water off during the lathering process.
And speaking of lathering, are you doing it for a minute, two minutes, three minutes, maybe more? If you lather for three minutes with the shower running, and then you rinse and repeat, you’re wasting a lot of water.
Another factor that determines if you’re wasting water in the shower is your showerhead. On old showerhead can use up to five gallons of water per minute, according to the USGS. However, a low-flow showerhead only uses two gallons of water per minute.
The fabulous shower below has six body sprays, fixed and hand-held shower heads, as well as a rain shower head. If you’re using all of these bells and whistles, you’re probably wasting a lot of money in the shower.
One way to evaluate your use of both water sources is to take a timed shower to see how long it lasts. Let’s say it was a five-minute shower. The next day, run water in the bathtub (and try to adjust the faucet level so it’s similar to the same water flow you have in the shower). Again, set your timer so you can determine if you reach your typical bathtub level in more or less than five minutes. If it takes longer to fill the bathtub, you’re using more water to take a bath.