We decided to take the tap water subject a little further and be more scientific. We called the Office of Waterworks Seoul Metropolitan Government and asked if they can come to an apartment in Seoul and test Arisu, the name they made up for Seoul tap water. Thankfully, they agreed.
The testing took place inside an apartment building in Seoul. It was built approximately 25 years ago. Like many other apartment complexes in Korea, tap water is stored in large water tanks and distributed to each household through pipes. When water pressure fluctuates in those very old pipes, rusty water can come out. So we thought the place is perfect for testing tap water. A positive test result would mean that tap water in other apartment buildings is likely to be safe as well. (FYI, buildings constructed in 1994 or later should have galvanized stainless water pipes for preventing rusting as it is required by law.)
Test Equipment Used
They brought a DR/890 portable colorimeter to run tests. (A colorimeter is an instrument used for water quality analysis.) According to the manufacturer's website, the DR/890 model is capable of testing up to 90 parameters, which include the following:
Aluminum, ammonia, barium, benzotriazole/tolyltriazole, boron, bromine, chlorine dioxide, chlorine, chromium, COD (chemical oxygen demand), color, copper, cyanide, cyanuric acid, detergents/surfactants, dissolved oxygen, fluoride, hardness, hydrazine, iron, manganese, molybdenum, monochloramine, nickel, nitrate, nitrite, nitrogen, oxygen scavengers, ozone, pH, phosphonates, phosphorus, silica, solids, sulfate, sulfide/hydrogen sulfide, tannin/lignin, TOC (total organic carbon), toxicity, turbidity, volatile acids, and zinc.
They ran tests for five different variables: copper, iron, pH, total chlorine residual, and turbidity (clearness of a liquid). We kept the tap running for about 20 minutes before any testing began.
|copper||0.03 mg/L||below 1.0 mg/L|
|iron||0.14 mg/L||below 0.3 mg/L|
|pH||7.1||5.8 ~ 8.5|
|chlorine||0.11 mg/L||below 4.0 mg/L|
|turbidity||0.27 NTU||below 0.5 NTU|
The officials stated that the tap water is safe for drinking. They also mentioned, several times, how the apartment building is very old and that Seoul City is only responsible for bringing clean water to the main base of each apartment complex. From that point on, the apartment management office takes over the responsibility. They also said that if tap water tastes poor, drinking bottled water is a good option. They explained that Arisu is not strictly 100% water. Chemicals like chlorine must be added to kill harmful bacteria so that people won't get sick from drinking tap water.
So there you have it. Tap water in Korea is safe. Well, kind of. News stories regarding tap water disasters are common in the media. A few months ago, a newly built apartment complex in Seocho-dong had contaminated tap water, which was declared not even safe for washing and bathing. Gangneung City in Gangwon-do had a similar problem only about a month ago. Maybe this is why Koreans don't drink tap water. Maybe we should have asked the officials if they drink Arisu. Nevertheless, it is kind of neat to give tap water a pretty name.