Linking London, by think-tank Centre for London, argues that new crossings would catalyse the development of up to 45,000 homes and 60,000 jobs by 2031, improve the productivity of firms in the area by over £55 million per year and cut cross-river journey times by up to 40 minutes.
The report makes the case that new crossings will "improve access to jobs, customers and suppliers, increasing business productivity and employment", while the increased accessibility "will also provide a boost for house building, so helping to tackle London’s severe housing shortage".
It argues that investment in new crossings is "so long overdue" that a package of four crossings should be built.
The first would be the Silvertown Tunnel, which is already being planned and is already "well advanced" in its technical preparations already. Mayoral agency Transport for London has estimated the earliest operational date to be 2021.
TfL is also considering a bridge or ferry at Gallions reach, but the report argues that both options would be inferior to the "superior, more cost effective option" of an immersed tunnel.
The two other crossings proposed would be a crossing from Belvedere to Rainham, and the Lower Thames Crossing, which would "augment the existing bridge and tunnel at Dartford".
The report suggests that the crossing should be funded by a combination of tolling and public finance.
The report was produced on behalf of the Commission for East Thames Crossings chaired by Lord Adonis, set up in spring 2014 to develop proposals for East Thames crossings.
But Friends of the Earth London campaigner, Jenny Bates, said: "New Thames road crossings will simply bring more traffic and worse congestion to the area, not relieve it.
"They would also bring more air pollution to the capital - and with current levels killing thousands of Londoners prematurely every year we have to cut traffic, not increase it."