So your water tastes like dirt. Does that mean there is dirt in the water? Not necessarily. There are many possible reasons for water tasting like dirt, but there is one likely culprit in the majority of cases, and you have likely never even heard of it.
It turns out, your water doesn’t taste like dirt because of any actual dirt or sediment present in the water. No, it’s actually something else entirely.
The number one cause of water that tastes like dirt
Geosmin is a compound produced by certain kinds of bacteria found in soil, such as Streptomyces. It’s also produced by cyanobacteria, which is commonly known as blue-green algae. Geosmin has what has been described as a earthy taste. In other words, it tastes like dirt. It is this same compound that has been accused of adding the taste of dirt to everything from catfish to certain varieties of wine!
We are extremely sensitive to geosmin. In fact, we can sense its presence at absurdly minuscule concentrations – as low as 5 parts per trillion. In a liquid, as little as 10 nano-grams per liter will have you complaining about that “dirt-taste.”
In the summer time, when there are possible algal blooms, or algae present in your pipes, this taste may become even more apparent. In fact, if you notice that the dirt taste only seems to come from one particular faucet in your house, it is likely because the pipes leading to that faucet have some algae in them.
If your tap water comes from local surface water, the taste of dirt may fluctuate with the lifecycle of Streptomyces bacteria. When these organisms die, geosmin is released in large quantities, causing the inevitable change in taste.
Water that is more on the acidic side does not have this problem, as the acid is able to neutralize the geosmin. This is why many fish dishes that feature bottom-feeding fish, like catfish and carp, use vinegar based sauces to temper the taste.
What can I do to get rid of that dirt taste in my water?
That’s a fair question. Now we know what causes it. What do you do about it?
Well, the easiest solution would be to run your water through a proper filtration system. You can poke around our site to see some options. A whole house filter or even a pitcher filter would help immensely.
If you wanted to eliminate all traces of the taste, invest in a solid reverse osmosis system, which is guaranteed to remove all impurities, including the geosmin.
Of course, you could also load up your water with vinegar, but you might not be too keen on the taste of that, either.
For more on the mysteries of geosmin, check out this paper, which talks about how geosmin is produced. If you have any of your own insights on this fascinating compound, feel free to leave them in the comments below.