https://www.ktoo.org/2019/09/23/anchorages-sewer-system-is-full-of-debris-now-theres-a-giant-vacuum-to-clean-it-out/

Sewage moves beneath the streets of Anchorage in more than 700 miles of sewer lines. But other items wind up in those lines, too, like toys, clothes and shoes.

Anchorage utility managers now hope a new high-powered vacuum system will help remove some of those things, improving flow and extending the life of the entire system.

“We’re able to clean in one week what used to take us a month, and we wouldn’t even get it as clean,” said Sandy Baker, the public outreach coordinator for the Anchorage Water and Wastewater Utility.

The utility began using the new equipment this summer, Baker said. First, a high-velocity jetter truck draws water from a hydrant and shoots it into the sewer main to loosen any blockages. Then a hydraulic power pack sucks it all up into a 25-cubic-yard vacuum box.

The vacuum box can hold up to 60,000 pounds of accumulated sediment and debris. Crews bring it all back to the South Anchorage operations center, dump it out, drain the water, dry it up, then haul it off to the landfill for disposal. By this point, it resembles a pile of dirt.