With a population of about 140,000, Hollywood is Florida’s 12th largest city. Most of its growth took place in the 1950s and 1960s. So like many cities, Hollywood is now coping with aging and, in some cases, crumbling infrastructure.

One example was a gravity-fed main sewage transmission line: 6,000 feet of 60-inch-diameter lined concrete eroding at the bottom and leaking at joints. To cope with the failing pipeline as well as continuing expansion in the 27-square-acre community, the Department of Public Utilities built another 66-inch main line parallel to the first.

But the original line couldn’t simply be abandoned; its capacity is still very much needed. Managers decided to rehabilitate it with a fiberglass lining. Sewage could be diverted into the new line during the work, but there was still a lot of groundwater infiltration to manage.

“We estimate that infiltration alone was letting in a few hundred thousand gallons daily,” says underground utility manager Ron Bolton.

Having successfully installed them in the past, Bolton’s team decided to insert an inflatable plug into the pipe via a manhole to dewater the line without tearing up the residential streets above. But they never worked with one so large.

“We placed the order and hoped for the best,” Bolton says.

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