Rush-hour traffic flow improved in the first three months of this year, according to a survey released yesterday.
However, gridlock is said to be rising again as the effects of major city roadworks are felt.
Shanghai ranked the second most congested major city in China in the first quarter, in a poll by Beijing-based AutoNavi.
It had a "jam index" of 1.94 — second only to Beijing's figure of 1.99, according to the study by the Alibaba-backed firm which has 300 million users for its mapping and navigation services.
This means that Shanghai motorists took 1.94 times longer to travel a route during rush hour than at other times.
However, this is an improvement on AutoNavi figures for last year.
Shanghai had the worst rush-hour gridlock of any major city in China, AutoNavi said last year.
In the final quarter last year the jam index for the city was 2.17 — though this was only the third worst city for that period.
But improvements look likely to be short-lived.
The partial closure on March 14 of the Yan'an Road E Tunnel, connecting Pudong New Area and Puxi Area, has meant more gridlock in the second quarter, said AutoNavi.
Since March, the jam index in Fuxing Road E. and Daxing Road — part of alternative routes following the tunnel closure — has jumped more than 20 percent year-on-year, according to the company.
The data is used to better manage city transportation, according to AutoNavi's vice president Dong Zhenning.
After Beijing and Shanghai, the most congested cities in the first quarter were Jinan (1.92), Hangzhou (1.91), Chongqing (1.90) and Harbin (1.86).
The survey covers 45 major cities in China, based on data from AutoNavi's driver users, taxi firms and public transport passengers.
