Biodegradable toilet paper and baby wipes which were stuck on something that still allowed water flow. Cracks, which are obviously present due to pipe fragments visible in the "blob" and leaks in the joints of the sewer line allowed water to escape at a rate which kept the upstream manholes from overflowing into the street and alerting the population while causing the blockage to increase.

From the looks of it this is some hokey 12 inch line with a waterproof seal only on the lower portions. I'm guessing this is a very low flow line or the paper came down in a very rapid time period.

The quality of the municipality's sewer department is evident as they don't have a rodding machine and hydrojetter to fix this.

Nose?

There's one on Memorial Parkway SW here in Huntsville, AL. Just like that. We never really think anything of it.