Best you aim for Norfolk instead
Seen that deep enough to reach the drivers seat of an artic, however deep that makes it, but the depth signs go up to about 8ft i think.
Extract from Cambs Times Jan '10
"Flood water drivers told: Excuses just won't wash.
Motorists who ignore road closures and tackle the flooded Welney Wash will be hit with a £60 fine and three penalty points if they are caught.
Several motorists have got stuck in the freezing waters this winter while trying to negotiate the stretch between Welney village and Ten Mile Bank. Diversions are in place but people are driving through and getting stranded in the floodwater.
Now police have warned drivers to expect tough action if they are caught flouting road rules. A spokesman said: "It is illegal and dangerous to ignore road signs. The signs are there for a reason - to protect the public.
The road is likely to be closed for several months and anyone caught ignoring the closure will get three points and a £60 fine." "
And a few days later.....
"Police U-turn on flood road
Motorists will NOT face a fine and penalty points for trying to pass the flooded Welney Wash on the Norfolk/Cambridgeshire border after police retracted their threat.
Following protests from a Welney haulage firm, police in both Cambridgeshire and Norfolk confirmed they will only ticket motorists who act carelessly. Last week, we revealed how Cambridgeshire police threatened motorists with a £60 fine and three penalty points for ignoring road closures while the wash is flooded.
It prompted protests from haulier Howard Kent to Norfolk police, because the wash road falls on the Norfolk side of the boundary. Mr Kent said: The road closed sign is square which means it is an advisory sign. Circular signs are mandatory. It's stated in the Highway Code.
Farmers always go through in their tractors safely and 4x4 drivers go past the closed sign as well, but my HGVs and our customers HGVs faced a 23-mile diversion to avoid a penalty when it was passable."
Keith Sainsbury, of Norfolk police's road policing/specialist operations, has told Mr Kent he was aware the threat "caused some problems and concerns in Welney". Mr Sainsbury added: "If anyone does try to cross when the Wash is badly flooded and becomes stuck or has obviously behaved recklessly, then we would consider what offences have been committed.
We would simply ask all road users to use their common sense and we will do the same." A Cambridgeshire police spokeswoman said: "We are not ticketing people for ignoring the sign but if we come across people driving through the flooded road without due care or carelessly a ticket may be considered."
So clear as muddy water then
Some local green ovals said that last year it got to about 3 feet deep for best part of a month! 
and warned me not to go through it when its that deep because it can flow very fast, not to mention kill my truck as I dont have a snorkel lol.
