If he was going down river it,s very easy to miss the height gauge, as it,s rather like a speed camara..you only see it when it,s too late! and it,s in diabolical state of repair,the next one,s on the bridge with the tide running on a spring very easy to get it wrong and then it,s too late,and if a novice as he was there,s big signs saying don,t turn near the bridge!!.
There,s normaly 8 ft 6 on a normal tide at high water..less on springs the tide runs at about 3 knots aswell.
I see boats coming down tide from the bridge and belt past at 8mph right past my berth so it,s from first hand knowledge i am actually thinking of taking numbers as a little tired of nearly spilling my drinks!!