'Arisu'
Gains Popularity
Waterworks Office gets the credit for tap water management efficiency

Pedestrians and subway riders in Seoul are given more opportunities to drink the capital's piped water, dubbed as "Arisu,"directly from the tap or from the bottle in such public places as streets and subways to quench the thirsty particularly during this hot, murky summer.
Under the catchphrase "Drink Arisu Any Time, Any Place,"the Waterworks Office of the Seoul Metropolitan Government, in charge of producing and managing the tap water in Seoul, has installed an Arisu piped water tap at the plaza of Namdaemun Gate and at the precincts of the Changdong Theater of the Seoul Foundation for Arts and Culture.
Twenty more taps will be made available at the capital? mass transit system by the end of August - nine locations at Subway Line No. 1, eight in Line No. 2, two in Line No. 3 and five in Line No. 4.
Waterworks officials, including Assistant Mayor Kim Heung-kwon, chief of the Waterworks Office, say the step is part of its efforts to enhance trust among the public about the quality of tap water and encourage more Seoulites to drink directly from the tap.
In a move to get a better understanding of the safety of the tap water, it has created the brand of the tap water, Arisu, named after the old name of the Han River called at the time of Goguryeo, an ancient Korean Kingdom. The new brand name, Arisu means a great river or water in view of the historical linguistics of Korean. They say that Arisu is placed at a top level as well as on a par with that of advanced countries in terms of its quality.
The office also operates "Arisu Campaign Corners"at subways in which PET bottles, each containing 350 ml of Arisu, are offered free of charge to subway passengers. Each center hands out 3,000 bottles of Arisu per day during the period between July 26 and Sept. 28 to raise the profile of the tap water brand. Besides, the Arisu Campaign Corners receive applications on tap water management. Officials at the waterworks office are sent to the applicant?house on the designated date to check tap water from the faucet, and if it passed, a certificate for quality tap water is issued. The tap water quality management system has been in place to ensure the quality of tap water.
Officials of the Waterworks Office, along with regional civic organization representatives and neighborhood ban and Tong heads, are dispatched to houses whose owners want to inspect such quality conditions of their tap water as residual chlorine and turbidity. The dispatched officials make checks on the conditions of water tanks and in-house tap water pipelines, which they believe may have an impact on their tap water quality, and they then issue certificates to houses that test for good quality. They present the outcomes of tests on tap water, water treated with purifiers and bottled water on the market at the present of applicants who want to see the first-hand testing.
A survey of 1,000 apartment residents, conducted in 2004 under a pilot program, showed that the percentage of respondents who use Arisu drawing directly form the tap without purifying it soared from the previous 2.4 percent to 11.3 percent, indicating a surging rate for tap water. Representatives of three parties - a city tap water committee, apartments and the Waterworks Office -jointly collected samples of tap water, water treated with purifiers and bottled water and assigned their testing to third-party research institutions, not state-run or public ones. All the tap water samples from the three apartment complexes - Okin Apartments in Jong-no, Samsung Raimian in Gongdeok-dong, Mapo-gu, and LG Apartments in Myeongil-dong, Gangdong-gu - passed the testing categories, but a few purified water and bottled water samples failed to do so.
Kim In-hak, an official with the Production Department at the Waterworks Office, said the outcome of the pilot program, designed to raise the trust of tap water and solving residents'complaints and grievances, indicated that the relevant residents?public rating for tap water have surged substantially because the testing was assigned to the third-party and civilian research institutions.
Kim said, "The program showed that there is no problem in the tap water flow process ranging from water treatment plant and water meters, which is under direct jurisdiction of the waterworks office, since a great portion of outworn pipelines, responsible for leakages, have been already replaced, but more trouble is related with the inner house pipelines and water tanks, whose management is handled by each household.
The waterworks office will soon announce the 1,000 apartment units to be covered by the pilot program during this year, he said.
Water management efficiency
The water management of the Waterworks Office has improved significantly. The office posted the retrieval rate or the ratio of charged tap water at 86.3 percent, close to that of advanced countries as of last May, a whopping 13.7 percentage point surge from 72.6 percent in May 2001. That means a curtailment of tap water of 662,000 cubic meters per day.
Officials at the waterworks office said the improved retrieval rate has led to management efficiency. A reduction of tap water has resulted in shutting down outdated and low-production water purification plants - Ttukdo No. 1 plant, Shinwol and Bogwang plants, thus curtailing production costs with facility maintenance and manpower costs. Such steps have saved 91.5 billion won in untapped water purchase, treatment agent and power costs since 2001.
They said the improved retrieval rate is owed to the replacement of dilapidated pipelines and efficient removal of leakages. During 2004, the office replaced 620 km-long, dilapidated pipelines and dedicated a distribution plant adopting a natural flow supply method instead of a pressured method, a measure designed to maintain a certain level of water pressure to prevent water leakages.
As part of its efforts to discover leakages, the office has introduced a nighttime minimum flow measurement, a scientific leakage monitoring method that detect leakages in a systematic and practical manner to facilitate quick repairs of the leakage, thus reducing water loss.
Under this procedure, the entire area is divided into 2,037 blocks.
Between midnight and 4 a.m, when tap water consumption is extremely low, and the controlling valve located at the perimeter of a given block and the valve at large-volume consumer businesses are closed to isolate the block. Then a self-recording flow meter is activated to measure inflow and water pressure of the inlet-distributing pipeline. From these measures, minimum flow during a specified duration is analyzed to judge the level of leakage.
The office aims to raise the retrieval rate to 90 percent, the level of advanced countries, by 2006 in a bid to enhance management efficiency. To this end, it plans to establish a tap water supply system, designed to make real-time checks on the flow of water at about 300 points across Seoul through the administrative on-time system as well as signs of regional leakages and ensure an appropriate level of supply.
The Waterworks Office plans to divide Seoul? tap water supply area into 78 mid-size blocks to elevate the retrieval rate.
Seoul City has undertaken a project to replace the 15,509 km-long dilapidated pipelines constructed before 1984. It will accelerate the replacement of outworn pipelines with the goal of having all of the pipelines, being replaced with new ones by 2007. The project will involve 449 km-long pipelines in 2005, 47 km in 2006 and the remaining 51 km in 2007. Seoul City also will renovate inefficient pipeline blocks on a yearly basis with the goal of renovating a total of 553 km by 2010.
Monitoring water quality
In order to monitor and detect changes in water quality at the supply source, the Waterworks Office undertakes tests once a month for 23 different monitored items at 30 monitoring places along the South and North Han River and downstream of the Paldang Reservoir, all located at the upstream of intakes. The monitored items include PH, mercury, DO, BDO, cadmium, lead, arsenic, coliform bacteria, total phosphorus, and etc.
To block the inflow of hazardous pollutants and maintain the safety of the source water, automatic monitoring is in place around the clock at six intake pumping stations to check seven monitored items, including such heavy metals as cyanogen.
To enhance tap water reliability and to produce and provide safer and better-quality tap water to its citizens, the Seoul Metropolitan Government has chosen 145 monitored items with reference of the list of water quality standards recommended by the World Health Organization. But many advanced countries, including the United States and European states, monitor less than 145 items. nw

Assistant Mayor Kim Heung-kwon, chief of the Waterworks Office at SMG
Bottled tap water Arisu
An Arisu campaign Corner at a subway station
A piped water faucet is set up to quench thirsty of visitors at the precincts of the Changdong Theater of the Seoul Foundation for Arts and Culture.