Police confirmed the 18-month-old was hospitalised.
She denied the city was "derelict", saying she visits frequently.
"The risks were well known."
The three council-owned facilities were revealed to be dumping contaminants down the drain.
The man died of his injuries on Friday.
"They've grabbed it and they taken a major piece of New Zealand's art history."
Jenn Hooper says "you actually have to be quite able" in order to use a public disabled bathroom.
A section of State Highway 1 has closed.
Dr Peter Sergel transformed a "council dump" into an award-winning international attraction.