For almost an hour, we sat together at a computer terminal, sifting through endless spreadsheets and work logs.

The code C-17 finally turned up in a series of municipal maintenance logs dated just weeks before the accident.

According to the entries, C-17 referred to a large drainage culvert right near the sharp north bend of the trail.

The official log showed that the culvert had been inspected twice in a single month.

The first inspection report listed the culvert as completely clear and working.

But a second report, filed just two weeks later, flagged the drain as badly blocked and marked it for urgent structural repair.