By driving vertical wood poles into the stream bed, and weaving them with debris such as logs, evergreen boughs and mud, their hope is beavers will take over their maintenance.
We humans create the problem then stick it to the animals to do our dirty work for no pay. Moreover, driving sticks into their sleeping quarters means they have to work day and night. Wait until the American capitalists read that story!
They will fire all their human dam maintenance people and hire cheap beaver labor. If there aren't enough, they'll demand the government open the border so they can bring in them "foreign" ones who will work for even less food taking away the jobs of real American beavers. Lastly, they'll outsource most of the dam building to cheap Chinese beaver companies who will pay even less and ship the completed dams to our shores driving other American Dam Maintenance companies into bankruptcy. Finally, the whole damn dam business will be in china and we'll be forever dependent on them so if they cut off our damn supply of dams, we'll be "up the creek".