OTTUMWA — A sewer running under railroad tracks downtown couldn't hold out any longer.
A 4-foot brick sewer line installed in the late 1800s collapsed Tuesday morning underneath the railroad tracks that run under the Jefferson Street Viaduct.
"It's an oval-type sewer, so the way the trains run it eventually starts making the top of it flat, and once it's flat, it has no structure, which makes it a lot easier to fall in," said Public Works Superintendent Steve Edgington.
BNSF ran trains on one of the two main lines since 8 a.m. Tuesday, closing the other to allow public works crews to work on replacing the collapsed sewer.
"We're anxious to get it done so we can get the other [rail] line open," Edgington said.
A BNSF track inspector found the problem during his daily inspections.
"While repairs are going on there [the one main track], we'll operate on the other main track," said Amy McBeth, BNSF director of public affairs for the region. "Later [Tuesday] evening we'll operate on the first track while repairs are moved to the other track."
Edgington said he had no idea yet how much it would cost the city to replace the sewer line.
"Normally the city pays for the sewer and the railroad pays for the tracks being put back in," he said.
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