THE OLD CITY OF LHASA
REPORT FROM A CONSERVATION PROJECT (98-99)
7. W A T E R A N D S A N I T A T I O N P R O J E C T |
7.1 General Situation: THF
1997 Study 7.2 THF Water and Sanitation Programme |
7.1 General Situation: THF 1997 Study
As seen in the previous chapter on the Ödepug conservation zone, toilets are usually the most vulnerable area in a traditional building, and the hygiene issue is one of the most urgent problems in successfully rehabilitating an old house.
The THF water and sanitation consultant arrived in Lhasa at the end of May 1997.
On the basis of the 1996 THF agreement with the municipality, the water consultant and members of the THF held several meetings with the Lhasa Municipal Water Office and the Lhasa Municipal Sewage and Roads Office. The existing water and sewage systems were studied and evaluated.
In the next step, the local water supply and sanitation situation in the THF conservation zone of 'Ödepug' was studied. In order to achieve successful rehabilitation of the neighbourhood as a whole, a block of new buildings located between Ödepug street and the Jokhang temple was included in the water and sanitation study and subsequent improvement project.
When the water and sanitation study was completed, the results showed that the water supply was not adequate. Some houses had piped water but only an intermittant supply. Some houses only had hand-pumps and a few houses had no water supply at all. The water, from both handpumps and standpipes, was found to be contaminated. The social survey carried out in parallel showed that water and sanitation was the field where most local residents wanted immediate improvement.
Before 1950, most houses were supplied by shallow wells in the courtyard, which have since run dry. Today, the Lhasa City Water Office pumps the water up from 60 meters deep by electrical pumps. An earlier storage tank on Chakpori has been abandoned because of lack of capacity. The pressure is generally not very high in the old city area, which happens to be about one meter higher that most of the new city areas.According to official health regulations for China, once a month chlorine is added to prevent contamination of the system.
The THF decided to run a mini-project to improve water supply. The project consisted of:
a) contracting the municipal water office to install a new water pipe in Ödepug street, bringing water from the Barkor water supply,
b) connecting the houses in the zone (including new houses adjacent to the area)
c) recommending to the residents that they should build good quality tap-stands for their connections.
The consultant designed the new network, and supervised the project, whilst local residents and Neighbourhood Office supported the work. Each house community was charged a nominal connection fee (which was paid in each case), since THF felt that this would make the residents feel more responsible towards the new installations. Some residents also dug new drains for their water supply. The work was carried out during September and October. By the beginning of November, 7 courtyards housing 48 families were provided with a new tap and 1 courtyard housing 13 families had had its connection upgraded from smaller pipes to the new 50mm pipe. Water pressure in the area had been dramatically improved by the water office's independent action prompted by THF's initiative.
Another parallel project involved the sewage office. The residents of a block of new houses (built around 1990) had a problem with their toilets. These were of the Chinese cess-pit type: the liquids are drained through an unsophisticated system of sewers into the Kyichu River and the solids accumulate in the cess-pit, to be emptied either by hand (which is usually the case) or by pumptruck (which was perhaps the original idea, but for different reasons cannot be done). THF contracted the sewage office to lay new sewage pipes on Sungchoera square, connecting the problem toilets. An old stone drain from the Jokhang temple had to be unearthed, but was repaired and covered again.
For more details, please refer to the separate report:
"Tibet Heritage Fund Water and Sanitation Consultancy Report, December 1997".
7.2 THF Water and Sanitation Programme
With water supply improved in the conservation zone, the sanitation issue has become an urgent priority.
In the spring of 1998, THF started a pilot programme to improve the sanitary installations in the houses in the Ödepug conservation area. For these works, THF begun training workers from amongst its team of 100 workers and trainees.
The present of water and sanitaion in Lhasa: toilet with scenic view, photo KDA
The past of water and sanitation: Bathroom of Fourtheenth Dalai Lama, installed in the 1950's, photo Josef Mueller
Three THF water and sanitation consultants (a British engineer and two German experts), all found the situation quite alarming. Some toilets had not been emptied and cleaned for several years, with vaults filled 2 meters high with excrement. There was considerable seepage through the walls and onto the streets. The lack of adequate infrastructure (such as pipe-systems, sewage treatment plans, lack of water and water pressure to operate flush-toilets) presented a major challenge.
The inhabitants made clear that the old night soil collection system, where farmers would do the collection to gain compost, was no longer working for several reasons. One is the widespread use of chemical fertilizer, which had diminished the demand for good compost. Another reason lies in the social changes that have transformed customs and ownership structures. Local farmers contacted by THF expressed little interest in compost, because of the difficulties in collecting it from the centre of a sprawling, densely-populated inner city area.
The toilets in old Tibetan houses are based on the vault system. The vault is on the ground floor. The bathrooms are located in the rooms above, with simple slots as openings. The walls are only protected from humidity by wooden splashboards. The need for more sophisticated reinforcement of the walls and the opening to the street was previously not seen as a priority, because in the old times the vaults where regularly emptied. Ashes were frequently added to soak up the excess liquid from the vault and to eliminate the stench. Today the toilets are emptied once a year or not at all, resulting in urine seepage damaging walls and contaminating the groundwater. In some cases, new houses built very close to old houses have made it difficult to reach the toilet service openings.
THF opted for a septic tank solution, such as the one being practice successfully for almost two decades in the neighbouring Himalayan kingdom of Nepal.
After emptying the vault, each toilet tract was checked for structural damage. In some cases the toilets had to be partially rebuilt because of serious damage. THF would then seal the toilet vaults from inside using reinforced concrete to prevent future infiltration. New drainage had to be provided. The bathrooms of repaired toilets have been tiled, and the walls plastered and painted for general hygiene improvement.
With the help of Mr. Manfred Wicki and the Swiss engineer, Danny Tscherrig, the first septic tanks were built according to Swiss-Nepali blueprints, with modifications to the conditions in Lhasa. Basically, the sewage will go into a sealed tank located in and below the original toilet vault. In several chambers, the sewage is treated by bacteria and reasonably clean water is being released into the nearest available drainage pipe. Flushing is either mechanically where pressure allows, or by poor flush (i.e flushing with a bucket of water).
THF has also built a public toilet, in traditional Tibetan architectural style but with the septic tank solution, at the western end of the conservation area.
For more details, please refer to the 1998 THF Water and Sanitation Report.