Water Flow

One of the District's pumps.

Floating on the Slough.

Jasper and I went on a tour of the Multnomah County Drainage District headquarters on a rainy winter day.  District Engineer Byron Woltersdorf lead the tour, explaining how they use a complex system of pumps, levees, and the Columbia Slough to prevent the Columbia River from overflowing its banks and flooding Portland.  Every year, there is an Army Corps of Engineers inspection. Any problems must be corrected immediately, in order for homes and businesses in the surrounding flood plain to remain safe and to be able to purchase flood insurance.  A big part of that is maintaining the levees.  They look just like embankments, but Mr. Woltersdorf explained that they are carefully engineered sand constructions, susceptible to erosion. the District's pumps can pump 280,000 gallons of water per minute, which he said is faster than a speeding bullet. They have gates which prevent logs from flowing into their pump stations.  They also have a machine which clears smaller debris from the pump intake.  Of course, someone had to ask what the weirdest thing was they've found in the debris.  Mr. Woltersdorf said that he thought it was definitely the head of a butchered elk which someone had tossed into the Slough.  

Apparently beavers are quite a nuisance for them.  He said that there are about 3500 of them in their district, and that most of the beavers are no trouble at all.  But when one decides to do what beavers are famous for and tinker with the waterways to suit their own purposes, they have to be killed.  He said that live trapping of beavers is prohibited in Oregon without a permit, and that the drainage district is not given permits to live trap and relocate them. 

Byron Woltersdorf explaining the behind the scenes technology.

An automatic debris removal machine.

The top of a levee.