Water Quality Opening Services

Date 2014-06-11 Category Water Supply (Arisu) Updater scaadmin
Last Update


Arisu Quality Verification System

-  During the first implementation stage from 2001 to 2007, our water quality inspectors visited about 60,000 residences every year to inspect tap water quality for free.

-  From 2008 to 2010, the magnified implementation stage, the Seoul Waterworks Office is going to inspect all 2.6 million households in the city. Water quality has been verified for 680,000 residences in 2008, and the remaining 1.92 million residences will be visited by the end of 2010.

 ∙ 2008: 0.68 million households (completed)

 ∙ 2009-2010: 1.92 million households

Seoul Water-Now System

 - The basic plan for a “Seoul Water-Now System” was established in 2001. Approximately KRW 4.8 billion was invested over the next five years, with the system actually beginning in 2005.

- From March 2008, since information on water quality - turbidity, pH level, residual chlorine - at a total of 72 spots (6 intake plants, 6 water purification plants, and 60 locations along drinking water supply routes) has been made public online, residents have direct access to information on their tap water quality.

 ∙ Total number of spots where water information has become public: 72 


A transparent, reliable water quality monitoring system in which citizens can participate

Background and Goal

-Seoul’s tap water, 'Arisu,' meets all 145 water quality inspection items recommended by the WHO, with safety verified by two US organizations (UL & NSF) specializing in product quality analysis and known for their strict standards. The quality of Arisu is comparable to tap water in developed countries, and in some cases, even superior. 

-Despite these facts, Seoul residents continue to be suspicious about its quality for no apparent reason and avoid drinking it. 

There has been no monitoring system to directly verify the quality of tap water in each household.

That has resulted in few people drinking it, increased sales of bottled water, reckless underground water development, an inflated trust in water purifiers (and contamination through their poor management), and greater waste of water resources. These serve to threaten people’s health and cast significant doubts about the quality of public services (tap water supply, etc.)


Improve confidence in tap water through unparalleled supply services


Trial Strategy

-Free water quality verification for all Seoul residences (Arisu Quality Verification System)

-Real-time online availability of water quality information (Seoul Water-Now System)

Obstacles & How They Were Overcome

Although enduring a shortage of funding and manpower at the beginning of the two services, as the revenue water ratio improved water leakage decreased, and office downsizing reduced production costs. Greater efficiency and productivity have been the result, allowing us to bring more inspectors onboard and initiate a free water quality verification system: the Seoul Water-Now System.

Resource Expenditures

Arisu Quality Verification System

- From 2001 to 2010, the Seoul Waterworks Office has plans to invest about KRW 15 billion and 40,000 man-days every year to complete the initiative by 2010. As of 2008, it has verified water quality at 1.1 million residences for free.
   ∙ Total investment: KRW 15 billion
   ∙ Total number of man-days/year: 40,000
2001-2007: 0.44 million households (completed)
2008: 0.68 million households (completed)

Seoul Water-Now System

- Between 2001 and 2005, KRW 4.8 billion was invested to establish the system. An additional KRW 1.4 billion will be invested until 2009 to expand it.

   ∙ Investment:  2001-2005 (KRW 4.8 billion) / 2008-2009 (KRW 1.4 billion)


Residents of Seoul can now verify the quality of tap water, online and in real time, which is supplied to their homes from water purification plants located in the surrounding area (Seoul Water-Now System). They also have access to water quality inspectors who can visit their houses for a free water quality inspection (Arisu Quality Verification System).
- These two services have the potential to clear up suspicion of water quality and dissatisfaction with services, finally gaining people’s confidence through greater transparency and accountability.
- In accordance with such a boost in confidence, the number of people drinking tap water has recently jumped more than 20%.
- About 76% of households who have seen the Arisu Quality Verification System in action expressed greater trust in tap water.
- More people drinking tap water helps conserve groundwater resources, reduces management costs for all, and the costs of purchasing water purifiers and bottled water for individual households.


To maintain this growing trust in Seoul’s tap water, the Office of Waterworks plans to continue the two systems on a sustainable basis for the future.

- Especially for the Seoul Water-Now System, considering that it is an electronic system, continual maintenance is all that is needed.

- In an environment of falling trust in tap water at home and abroad due to reckless development of groundwater resources, our invaluable water resources are being depleted. Providing clear evidence of tap water quality to citizens directly can continue reversing these trends. 

This is especially true if other nations and other local governments in Korea use this system to increase the use of tap water for drinking and thereby reduce the destruction of groundwater resources from poorly regulated development.

International Recognition

The winner of the 2009 United Nations Public Service Award






Department / Contact

  • International Relations Division  /  82-2-2133-5376  /  international@seoul.go.kr