Paul Fabricius, 57, told The Mail on Sunday when his grandson, Noah Bailey, attempted to play with his model battleship in a Chiswick Business Park pond, park security guards stopped him based on unspecified regulations.
"We were informed that the business park had rules, albeit undisplayed, and they had to be enforced and that included toy boats and dogs paddling," Fabricius said of the recent incident.
Fabricius said when he questioned a guard about the ban on toy boats, he was told the toys can potentially frighten fish in the pond.
"It's just nonsense. How can it frighten the fish? It has only got a tiny electric engine. It gets overtaken by the ducks!" Fabricius told the Mail.
A spokesman for the park security team said the rule is based on previous instances of disruptive behavior.
"We have had quite a few people come to the lake to use their model speedboats which is unacceptable," the unidentified spokesman said.
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