The foam caught my eye first. Then I heard the roaring sound of falling water under this access point (aka manhole), where one sewer pipe cascades “water” into a lower pipe.

Now, we’ve all heard that Ottawa’s sewage is cleaner than that in most other cities (due to the NCC buying out most industrial land users, and due to the large amount of relatively-clean storm water we stuff into our sewage-sewers) but I did not expect to find soap suds cleaning the pipes.