Norfolk, Va. - It looked like a deep-sea diving mission, maybe to explore a sunken wreck or salvage a submerged treasure. But when a pair of divers descended Wednesday morning, it wasn't into the ocean. They disappeared into a manhole, right in the middle of the lawn at the Chrysler Museum.

For hours Wednesday, they were underground and underwater, exploring the catacombs of a buried culvert and all the drainage pipes attached to it. The topside crew for Moffatt and Nichol Engineers told us the divers could essentially walk through the six-foot pipe, tethered by a cord carrying both air and their voices. The divers used hammers, rulers and a camera to document every connection from the museum to the Hague.

We heard frequent reports of misaligned or shifted connections, and pipes filled with swampy silt, all pretty typical of an older city's underground drains. Normally, rain is funneled through the pipes and to the Hague. But during storms like last week's lingering drencher, rising water from the Hague flows the other way, into Norfolk streets.

When the divers emerged from the ground, it was time for a quick lunch. An hour later, they descended once again, into another branch. The engineering firm with an office in Norfolk said it was working on a contract with the city, and referred questions to Norfolk. So we asked Norfolk officials today what they were looking for, and how much they're spending for the survey, but no one from the city responded.