OK now I am thoroughly convinced that the design details of the creek work were part of a Career Day project in a local high school because no way could a professional engineer who understood that he was dealing with intermittent storm drain runoff have designed a thing like this. Also, the purpose of the BFRs is revealed:
Now people who know about erosion tell me that the bed of the creek should be compacted and lined with large gravel embedded in cement. It would appear from the evidence here that the small size tamper, the kind you would use to prepare for a sidewalk, is going to gently flatten the soil and then gardener’s landscape cloth will be employed. No idea about the lederhosen.
Somebody on this job has an artistic soul. Although the weir is looking a little bit aslant to me (I’m sure that won’t affect its stability or lifespan. Right?), it does have a darling stylized flower worked into the pattern of wire mesh. And what else can we call the tiny tamper perched on top of a BFR but an art installation?
My yard is at the start of the creek – I hear that 2 houses away at the end of the creek work, there’s a pool of standing water between the weirs. I haven’t had the heart to go look at it yet. But really – how nice for the baby mosquitoes.
Cripes Suzette 
Maybe it’s some secret government experiment designed to make the residents think the end result will force running water to behave itself and act civilized. Or they’re trying to prove that “still waters run deep” is a big lie.
I’m thinking you’re lucky to be at the head of this thing. It looks like someone downstream is going to experience a dam made from dislodged boulders that tumble away until they pile up at a bottleneck. That person had better have flood insurance.
Good point. Also, the boulders will ‘capture’ any limbs or debris to make things even worse.
Too bad about the boulders. Looks like it would have been one fun ride on an inner tube.
I’m guessing the BFR’s are for reducing laminar flow, which will help prevent concentrated scouring of the bottom. It’s a good idea, as long as debris doesn’t create a dam, which may cause water to build above the gabions and scour the adjacent bank.
Let me know if they stock it with trout.