Options for a new Thames crossing include a scheme that would pass through "environmentally sensitive areas" and cost up to £5 billion.
Concerns have been raised that plans for cameras to replace toll booths at the Dartford Crossing could leave motorists with huge fines.
Motorists will be fined £105 if they fail to pay tolls at the Dartford Crossing under plans revealed by the Highways Agency.
The start of the working week meant that traffic built up around the crossing from early this morning.
Video. Rush hour traffic was brought to a standstill last Friday evening as bomb hoax saw the Dartford Crossing closed. Drivers were stuck in their cars till almost midnight. Over the weekend a man was arrested and detained under the Mental Health Act.
A new charging scheme to ease congestion and improve traffic flow at the Dartford-Thurrock River Crossing will go ahead next year.
It follows two consultations which found overall support for new legislation for drivers who don't pay.
The free-flow technology will enable motorist to go through without stopping at the barriers.
The MP for Thurrock has met the Secretary of State for Transport to discuss plans for a new Thames crossing. Also on the agenda were improvements to the roads leading to the Dartford Crossing, and free-flow tolling.
The MP has repeated a call for local residents to get free passes for the bridge and tunnel.
The government has announced the start of consultations over building a new Thames Crossing. There are three options: Dartford, Swanscombe and a site near Gravesend. The cost could top £5 billion.
We speak to Roads Minister Stephen Hammond, Richard Knox-Johnston from CPRE Protect Kent, Cllr Bryan Sweetland from Kent County Council and Natalie Chapman from the Freight Transport Association.
The Government has today begun consulting on a second Dartford Crossing. The options are:
(1) at the site of the existing A282 Dartford-Thurrock crossing;
(2) connecting the A2 Swanscombe Peninsula with the A1089 in Essex; o
(3) linking the M2 with the A13 and the M25 between junctions 29 and 30.
The Freight Transport Association says it's long overdue but environmentalists say they're not convinced it's needed.
The operator stayed on the phone with the man to reassure him until a patrol located his car - and drove the vehicle through the tunnel with him as a passenger, before sending him on his way. He was too scared to drive through the Dartford crossing.
Inspector Paul Sellwood, of the Kent Police roads policing unit, said: "This incident shows how seriously we take all calls we receive from members of the public."
A terrified motorist with a fear of bridges called police out for help - because he was too scared to drive through the Dartford crossing in North Kent. The driver took a wrong turn and called Kent Police when his satnav directed him to drive over the river crossing at 9.30am on Monday.
The man, who did not know the area, suffers from gephyrophobia, an anxiety disorder brought about through a fear of crossing bridges. The force control room operator said he would be passing through the tunnel, not over the bridge, but the motorist confessed he still felt too scared.
VIDEO: A new tunnel under the Thames in East London could drive up the cost of using the Dartford Crossing according to Dartford council. It's worried new, increased tolls at the proposed Silvertown Tunnel could mean charges will be forced up at Dartford.