East London roads desperately need the Silvertown Tunnel to support a creaking and unpredictable Blackwall crossing, according to Transport for London.

TfL is planning a series of cross-Thames links between Tower Bridge and Dartford to dilute the impact of increased traffic.

Green campaigners have questioned why the first of these crossings will run alongside Blackwall rising in the Greenwich peninsula.

TfL's new head of planning Richard De Cani told The Wharf this week it was a no-brainer.

"Blackwall's got limited capacity, limited clearances for height and one of the tunnels was built in the Victorian era and designed for horse and cart," said Mr De Cani, speaking from his office in Canary Wharf.

"You can see the problems in the morning peak with traffic going back to the Sun-In-The-Sands roundabout. When anything goes wrong with the tunnel -an incident with a flat tyre or a vehicle trying to get through that's too tall - the impact is huge.

"The idea you can do nothing at Blackwall is not realistic in terms of traffic, air quality or the impact on the economy. There's a strong case of developing Silvertown sooner but, of course, that has to be done in the context of this package."

Silvertown is due to be completed by 2021/22 with crossings at Gallions Reach and Belvedere following around four years later.

Campaigners fear Silvertown will be built but the other crossings closer to the estuary will be forgotten.

Mr De Cani, pictured above, urged critics to judge TfL on its record of delivering public transport crossings.

"The whole development of Docklands was about providing rail crossings," he said. "That package has been followed through with the DLR, Jubilee line, upgrading of the old East London line and Crossrail. The logic has been to support the changes to support growth. The same logic exists for the road network."

Transport for London's Richard De Cani

However, much rests on the troublesome crossing at Gallions Reach which was blocked at a public inquiry and has already once been scrapped by current London Mayor Boris Johnson.

Mr De Cani insists the link now has cross river support from boroughs which wasn't there before.

"What's different now is the bridge or tunnel will be smaller and hold less traffic.

"Also if Silvertown is there and Belvedere arrives at the same time, concentration of traffic flows are spread."

Another bonus of building Silvertown, he said, was increased bus links to south London. Currently just one bus uses Blackwall.

Mr De Cani said: "We get asked about the section between Eltham and Canary Wharf and Charlton and Canary Wharf. One of the two lanes in each direction of the Silvertown Tunnel will be for buses and heavy goods vehicles only, so it means you can get more direct services from south of the river to Canary Wharf."

More public transport access could also arrive through the DLR sharing the Gallions Reach crossing, but that would suggest another tunnel, rather than a bridge.

"A bridge would need to be 60m in the air - as high as the cable car - which means it's very high to get from down to where it is to the bridge and then away," said the TfL director.

"DLR is probably more feasible with a tunnel than a bridge. If it's not the DLR you can connect buses on the route."