Mains water has returned to the northern Chinese city of Harbin after a toxic chemical leak, but with a warning it may not yet be safe to drink.
Residents of Harbin are relieved but not yet back to normal
Provincial Governor Zhang Zuoji took the first drink after supplies were reconnected, Xinhua news agency said.
But authorities say general supplies may be too dirty after being cut off for five days and lying in pipes.
About 3.8m people in Harbin lost their water supplies after 100 tonnes of benzene spilled into the Songhua river.
The spillage was caused by an explosion at a petrochemical plant upstream in Jilin.
Beijing has begun an inquiry into the spillage on 13 November.
For the past five days, Harbin's residents have been relying on bottled water and water delivered by lorries.
13 November Explosion at petrochemical plant, Jilin city
21 Nov Water to Harbin city cut off; local government cites mains maintenance
22 Nov State media say water could have been contaminated after the blast
23 Nov Authorities admit very high levels of benzene have been found in the water
23 Nov Authorities say 100 tonnes of benzene emptied into the Songhua river
26 Nov China apologises to Russia, where the pollution is expected to arrive in the coming days
Inspections on Saturday evening revealed that water quality in the Songhua river upstream of Harbin had returned to national standards, Xinhua reported.
The restoration of supplies at 1800 (1000 GMT) on Sunday came five hours earlier than expected.
Although residents greeted the return, the government said it would make media announcements when the water was safe enough to bathe in or drink.
TV stations will use a traffic light-style system to inform residents about water quality.
A red indicator will mean the water is unusable, yellow that it is suitable for bathing only, and green that the supply is fit for drinking.
"We still have to wait a little longer," said Harbin resident Wang Yixin, although she vowed: "Tomorrow we'll clean the whole apartment and wash all our clothes."
To quicken the clean-up, water was discharged into the Songhua from nearby reservoirs to dilute the spill, while the army installed new filters at Harbin's water plants.
Tests showed levels of nitrobenzene in the river, Harbin's main source of water, had dropped below the official safety limit.
On Friday, levels had been three times above the safety limit, Xinhua reported.
The toxic leak passed Harbin early on Sunday morning, said Lin Qiang, a spokesman for the provincial environmental protection bureau.
As it flows downstream, it is likely to contaminate Russia's Amur river, which feeds water to more than 500,000 residents of the Khabarovsk region.