Other expert witnesses at the inquest have disagreed with Benn’s view about the type of screen used at the culvert at the time of Noah’s death.
Benn has favoured the department’s use of a debris screen, with wider bar spaces, as a preferred flood prevention measure.
The inquest has heard that this type of screen enables people to enter it.
Other expert witnesses have told the inquest that they believe a security screen, with narrower bar spaces, should have been used at the site to prevent unauthorised access.
But Benn and witnesses from the Department for Infrastructure have told the inquest that they believe security screens pose a greater risk of potential entrapment.
Benn also told the inquest that it was “my mistake” to inform the inquest that the death of a man at a culvert in England was linked to a security screen at the site.
When it was pointed out to the witness that there was no security screen issue at the English site at the time of the tragedy, he replied, “there’s an error on my part”.
The coroner, Mr Justice Rooney, pointed out to Benn that three examples of culvert related deaths he (the witness) highlighted to the inquest were not arising from security screens.
Officials from the Department for Infrastructure watched from the public gallery as Benn gave his evidence to the inquest.
He is due to complete his evidence at a future date.