Nevsky Prospect turned into a lake last Wednesday.
A sudden change in the weather dramatically illustrated the dilapidated condition of many St Petersburg buildings and part of the city's water system.
Century-old water pipes under Nevsky Prospect near the Sever Restaurant (46 Nevsky Prospect) collapsed last Wednesday at about 3 pm, causing a five-square-meter (six sq yd) hole in the road and flooding the city's main thoroughfare.
On the same day, the cornice of the weather-beaten tower of the Kunstkamera fell onto the museum's roof.
The following day other pieces of the Kunstkamera -- also known as the St Petersburg Museum of Ethnography and Anthropology -- were removed by climbers from the BMP Kompakt company.
The flooding on Nevsky Prospect blocked the underground passage at Sadovaya Ulitsa and movement in the city center.
The underground passage was evacuated, with people wading out through water up to their knees. At least one unfortunate car parked along the street had water halfway up its doors.
City water supplier Vodokanal's emergency service stopped the flow in just 30 minutes and prevented any water from penetrating the Metro or adjacent buildings.
Movement along Nevsky was restored in little more than an hour. Vodokanal has been replacing the pipes along Nevsky and had already completed work up to Sadovaya Ulitsa from Vosstaniya Ulitsa.
The company would have been able to reach the point of the collapse if it had another three days to work, said Ivan Alexeyev, Vodokanal's general director.
According to the renovation plan, the rest of the pipes from Sadovaya Ulitsa to Palace Square should be completed by the end of the year, Mr Alexeyev added.
Climbers repair the damage to the Kunstkamera as the
snow comes down.
Kunstkamera staff said the museum's roof had been in a state of emergency for many years, yet no money has been allocated for repair work.
More than 20 billion roubles ($4.1 million) would be needed to complete the repairs, according to some calculations.
After the incident, the Mayor's Office culture committee allocated 200 million roubles ($41,500) to pay for the climbers' and for preparatory work for the repairs.
The director of the museum, Alexander Mylnikov, said last week that the damage was the direct result of underfunding over a number of years.
St Petersburg Mayor Anatoly Sobchak responded, "If the director had turned to me a year ago, I would have made the money available.
"If he had done this it wouldn't have happened. The roof has been leaking for two or three years. This is incompetence."
On Monday, Mr Mylnikov catalogued a list of 10 letters sent to administrative bodies both in St Petersburg and in Moscow in the period 1993-4 outlining the situation at the museum and the need for extra funds.
Four of these letters were sent directly to Mr Sobchak.