Police yesterday arrested a man as he allegedly was removing copper siding and rain gutters from the roof of a Board of Water Supply pump station in Kapahulu.

It was the third recent case in which thieves have stolen or tried to steal copper or brass fittings from public facilities on O'ahu. Such metals have resale value as scrap.

Unlike the previous two cases, police yesterday made an arrest and recovered the metal parts.

A resident of a nearby apartment building called police after seeing a man walking on the roof of the Board of Water Supply building shortly before 4 a.m., police and water board officials said.

A responding patrol officer caught the man removing the copper siding and gutters and arrested him on suspicion of trespassing and theft. The water board sent plant maintenance officials to see if the recovered copper could be salvaged, but it couldn't, board spokeswoman Su Shin said.

The copper had been ripped from three sides of the roof. Preliminary estimates put the cost to fix the damage and replace the siding at more than $5,000.

"Obviously it's a problem for us since we have to replace it. We don't know (exactly) what it will cost because we have to put it out to bid (but) we expect it to cost more than $5,000," Shin said. "We are not going to put copper back so hopefully the cost will be less."

The copper from the roof was used to divert rainwater and did not affect pump station operations, she said.

On May 12, state Department of Transportation officials said thieves have stolen copper wire from light fixtures on the H-1 and H-2 freeways. The thefts cost taxpayers more than $100,000 in parts and labor and more than 100 street lamps are still out in Central and Leeward O'ahu. Two days before that, city officials disclosed that thieves had taken $10,000 worth of brass flush valves from 28 park restrooms.

Reach Peter Boylan at pboylan@honoluluadvertiser.com.