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Unidirectional Flushing team hits milestone 

Blog Post
Undirectional Flushing (UDF) is an important process we undertake to keep our system free of unwanted debris and ensure the quality of Portland's drinking water.
Published
Environmental Technician Mikkel Holt explains the work him and his crews do to flush the water mains and hydrants from the system.

The UDF crew in action:

Water bureau employee Brian Scott displays a map of planned water flushing operations.

UDF crew lead Mikkel Holt holds a binder that provides vital information ahead of any flush. All the maps are put together by Engineer Brian Scott. “If Brian didn’t do such a great job with this, I couldn’t do my job. This book tells me where I need to open valves, where the valves are that need to be closed, and lays out all the assets I need to be mindful of such as Water Quality monitoring stations,” Holt said.  

Water bureau employee Laura Ispass leans on a fire hydrant to check a reading.

Utility worker Laura Ispass closes a hydrant off Southeast 138th Avenue. In the last two years the UDF team has flushed approximately 7,000 pounds of debris and sediment from our distribution system. That’s about as much as an Asiatic elephant weighs.  

Water bureau employee Mikkel Holt stands outside and explains his work.

Holt remembers when the team started flushing at Kelly Butte two years ago. Neighborhood-by-neighborhood, flush-by-flush the UDF team is making major progress. “To know that within two years we were able to get to this point, knowing that we have the goal of flushing the entire system before the filtration plant is online, I feel pretty confident that we’ll be able to reach that goal.”