What's lacking about the Kerch Strait land bridge, between Crimea and Russia?

Question

In this video, retired US Army General and former CIA Director David Petraeus tells CNN's Jake Tapper how the Ukrainian people have aided their army in killing multiple Russian generals. CNN has not been able to confirm the killings.

At 3 minutes 59 seconds, David Petraeus and Jake Tapper discussed military logistics around Crimea:

Petraeus: It's also that you have a land line of communication between essentially Russia and Crimea that doesn't require the bridge here.

Tapper: Let's go back to the corridor here. This is what they had previously, all they had was this teeny little bridge which you can't really get everything you need ...

Petraeus: That's right.

Tapper: ... if you're in the Russian military, across this bridge. It's just not big enough.

Petraeus: That's right, that's right.

Is Petraeus referring to Kerch Strait Bridge, a pair of Russian-constructed parallel bridges, spanning the Strait of Kerch between the Taman Peninsula in Russia and the Kerch Peninsula of Crimea?

Why isn't it big enough? What does Russia need to accomplish that can't be accomplished with this 'teeny' bridge?

Answer 1

The bridge is easily sufficient for combat vehicles themselves.

Russian tanks weigh 46-48 mt (a very narrow range all of them fit into). Trucks are generally limited to 80,000 lbs, or 36 mt. It's not a big difference, well within the safety headroom, so Russian tanks would have no problem crossing any truck-capable bridge.

The rail line is also sufficient for war logistics. A high-volume train line can carry up to 7 trains per hour at ~50 cars per train. At 60,000L per car, that's up to 500 million liters of fuel per day. Wartime caution and difficulties will reduce this.

A T-90 carries 1600 liters of fuel, about enough for a day of active operations. 1,000 tanks will thus consume about 1.6 million liters a day. Add another 25,000 lighter vehicles at half the consumption of a MBT each, and you can estimate ~20 million liters daily. That's 4% of the rail line's maximum peacetime capacity.

But there is of course the issue of the bridge's vulnerability. Since Russia considers Crimea its home soil, the bridge is protected by its nuclear deterrent. That could be tested, but the probability of a response is high, which would either end the war or start a new one. Still, in a full-scale war, a single bridge cannot be relied upon.

What the bridge is not sufficient for is distributing this fuel across the country. Once the train arrives to a station, it has to be unloaded and the fuel transloaded to trucks to carry it further. And this isn't done at a rate of 20 million liters per hour - this kind of transloading infrastructure just doesn't exist, anywhere in the world.

A land bridge can be traversed by ground vehicles directly. It can be used to lay temporary pipelines and railways. It also offers opportunity to use or install new infrastructure for fuel transloading.

Answer 2

A lot of commentary has centered around the over-water bridge to Crimea. This is a "Red Herring" so to speak. Russia needs 'open year round' warm water ports for commercial shipping expansion (oil/gas transport not dependent on pipelines thru hostile/NATO territory) and to base naval operations. There was longstanding agreement between Russia and Ukraine to share naval base at Sevastopol but that wasn't good enough for Russia. Also, the Donbas region has long been place of plentiful resources (coal & iron, etc) and its associated manufacturing strengths.

ALSO... a couple well placed cruise missiles make the Kerch Straight bridge just another pile of useless rubble.