A survey by SonntagsBlick shows 29 major construction projects that are slowing down traffic on routes from one end of Switzerland to the other.
The newspaper calculates that speed limits are reduced to as low as 60 kilometres an hour from the regular maximum of 120 km/h along stretches of motorway totalling 75 kilometres.
Eleven projects are leading to tailbacks along the A1 Highway which runs east-west from Lake Constance to Geneva.
The longest one is an 8.5-kilometre section between Wiggertal, Aargau and Härkingen in the canton of Solothurn, where the speed limit will be reduced to 80 km/h until November 28th.
The project is expanding the motorway and a section of the A2 to six lanes.
In the canton of Vaud, the speed limit will be similarly reduced for a road widening project between Vevey and Chexbres until November 15th.
On the A2 motorway linking Basel to the north and Chiasso, in the canton of Ticino to the south, six projects are underway, although four of them are set to be completed before the end of this month.
A six-kilometre construction project between Diegten in the canton of Basel and Egerkingen in the canton of Solothurn, where the maximum speed is 80 km/h, is scheduled to be finished on Thursday (July 18th).
Other slowdowns on north-south routes include a four-kilometre section of the A13 motorway between Sufers and Spliigen in the canton of Graubünden, where the speed limit is 89 km/h until August 30th.
A four-kilometre stretch on the A-9 motorway between Villeneuve and Montreux in the canton of Vaud will cut maximum speed to 80 km/h until November 2013.
Traffic jams were reported over the weekend on routes from the Zurich area to Ticino and Italy as many holidaymakers began their vacations.
It won’t come in time for this summer, but the federal government is launching a pilot project starting in March 2014 that aims to use data from the mobile phones of motorists to get a better picture of traffic congestion.
This data can then be used to inform motorists by radio and navigation devices, as well as on electronic motorway signage boards, of expected travel times, according to a report from the Sonntag newspaper.
Under the three-year project, the data, supplied by Swisscom, will be filtered and analysed in a bid to accurately determine how fast vehicles are moving.
The 1.75-million-franc project will respect the privacy of mobile phone users, according to the report.