The school's state-of-the-art gymnasium has been trashed, as have the tennis courts.
"It's a real shame. It could have made a great facility for the Waverley community," Mr Spooner said.
He said police were called to the school two or three times a week but could not do much unless they caught someone in the act.
A security fence was put up around the school after it closed but that was recently removed. Mr Spooner said that was when the trouble began.
"The fence didn't prevent access, but it limited it. Since that came down, the vandalism has really accelerated."
A Hawera-based security firm has been employed but Mr Spooner said they seldom visited the school, except to put up some boards over a smashed door or window.
Waverley Senior Constable Brian Rook said he was worried that someone would get hurt there.
"These kids climb around on the roof or in the roof space. The buildings are becoming more and more dangerous, and one day someone is going to be seriously hurt.
"And the amount of broken glass around has to be seen to be believed."
Mr Rook said it was disgusting that the local community had to deal with the aftermath of the school closing.
"This school had the most beautiful buildings but they have all been wrecked. It's just an eyesore and a dangerous place."
Wanganui community patrol co-ordinator Laraine Sole echoed Mr Rook's concerns, saying it was only a matter of time before someone was hurt.
"Because there are tall trees all around the school, it is impossible to police it. We cannot even see into the school to shine a light around."
The site is owned by the Crown and a Ministry of Education spokesman said security was being reviewed.
"Security fencing was taken down because it was not proving to be effective. Local security has been employed since then but the problem is reported to be continuing," the spokesman said.
He said the ministry had no plans to use the site and it was going through a disposal process. He did not say at what stage that process was.
The land could be part of a Treaty of Waitangi settlement or sold on the open market. Mr Spooner said he just wanted to see the site used or got rid of - the sooner the better.