Safety Minute – Sweepers and Strainers
Sweepers and strainers are often pretty and look benign, until they try to kill you.
I think I dated her in college.
The outside of a curve in a river tends to undercut the bank on the outside of the curve. This often causes trees to fall into the river and cause an obstruction across the river.
The water can flow through these trees, but boats and people get caught in the branches.
A “Strainer” typically is an obstruction that is mostly underwater, or at the surface of the water. A “Sweeper” is an obstruction of branches and limbs that is still mostly above water.
They look fairly easy to avoid and usually are, but often the river current – the same one that undercut the tree and toppled it into the river, can sweep you into the Strainer or Sweeper before you realize it has you trapped.
Yup. Definitely dated her in college.
Be aware that the current that undercut the bank and caused the tree to topple into the river is able to sweep you into the exposed tree branches and catch you there. Due to Bernoulli’s principle trying to equalize the flow around both ends of your boat, your boat will probably swing around crosswise to the current, and then tip your boat over.
Once I managed to avoid most of a strainer, but two branches of the sweeper worked as the rails of a roller coaster and as the current was pushing me downstream, my boat was carried up along the rails and unceremoniously turned upside down and dumped back into the water. It was depressing how easily it did that.
A further danger is that, once you are in the water, the current can sweep you into and under the branches and keep you there. The only fatality during the annual Buffalo Bayou Regatta occurred several years ago when a participant got caught up in a sweeper, and the branches got caught up in his PFD, and held him underwater.
Just be judicious, and aware that they can catch you. Be safe out there!
See you On The Water!
Harmon