He had been doing more than sitting, however.
He told the Northland Age he had been threatened by some passersby so he had dug a trench around and under the bridge as an escape route.
He had already used it once, and it had worked perfectly, he said.
Read more: Protester takes direct approach against 'stinking' Mangamuku Stream
The Far North District Council was not amused, however. A senior manager said de Angulo had failed to comply with bylaws governing protests.
He was given 30 minutes to remove his signs, failing which the council would remove them for him.
The trench was to be assessed to determine whether any damage had been done to the bridge or its foundations.
The council said the issue of grey water entering the stream from Fairview Crescent has been resolved, while de Angulo's claims about leachate from rubbish in a nearby reserve was also polluting the stream were being investigated.