When night falls in Portola Valley, the darkness tends to be deeper than in nearby towns. The active encouragement of minimal light levels is one of many steps the town takes to maintain a rural character and to avoid an urban or suburban tone.

Now the town may be stepping toward a suburban tone of lighting at Town Center, at least for the next 12 to 15 months during the construction of a new library, Town Hall and community hall.

A reliable darkness could have been instrumental over the weekend of Aug. 4 and 5, when a thief or thieves stole an estimated $17,000 in materials from a locked equipment container at the construction site, said Sgt. Gary Brown of the San Mateo County Sheriff's Office.

The heist netted a jack hammer, several power tools, and a plethora of copper and brass fittings still in their boxes, Sgt. Brown said, noting that copper is a hot commodity on the black market.

While there are several equipment containers on the site, only the one with the fittings was broken into -- the earmarks of an inside job, Sgt. Brown said, adding that inside knowledge could result in the fittings' being stolen again once they're replaced.

Given that possibility, the site's apparent vulnerability at night and the length of the project -- a grand opening isn't expected until winter 2008 -- something needs to be done, the Town Council concluded at its Aug. 8 meeting.

"This is not going to get better; it's going to get worse," Mayor Ted Driscoll said. "We're out here in the middle of nowhere. I think we do need to take more action."

The council looked at the cost of hiring a private patrol to visit the site, and discussed asking managers of Town Hall's institutional next-door neighbor, The Sequoias retirement community, if they might make their night watchman available for a nightly turn or two around the site.

Ahead may be infrared cameras, posted surveillance notices, and lights, even lights controlled by motion detectors -- an idea discouraged in the town's design guidelines.

A Web camera is already mounted out there to record construction activities for a documentary film project. Bright lights could turn the camera into a security device.

"I think we should be aggressive about this," Councilman Steve Toben said. "Let's hit it real hard."

The Sheriff's Office will be on higher alert during deputies' patrols as well, Sgt. Brown said. "Nobody likes to lose $17,000 worth of merchandise on their watch."

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