I did not imply that these were "large rivers", just that they were not little ditches. There is quite a lot of room for streams of many different sizes within those two extremes.
Take Buffalo Bayou, the most important stream in my area, which runs for about 50 miles, starting in rural Fort Bend County to just southeast of downtown Houston where it becomes the Houston Ship Channel and then empties into Galveston Bay. From its headwaters to the western edge of the Houston city limits, it is managed by the US Army Corps of Engineers. From there to downtown, it is managed by the Harris County Flood Control District with USACE cooperation, and once it becomes the Houston Ship Channel, it is managed by the Port of Houston Authority.
From its headwaters to downtown Houston, much recreational activity takes place on the bayou. It is too narrow and shallow for motorboats, but many private kayakers and canoers, as well as canoe livery services, travel on it. Its width in this area is about 150 feet. From the headwaters to the USACE flood control gates, the surrounding land is rural for the most part, though exurban growth is changing that. From the gates eastward for about 12 miles, the bayou is bordered on both sides by public parkland, and from the end of that segment for another 13 miles it passes through private property, mostly upscale private houses with dense forest. Then it passes through a city park before opening up to a mix of smaller city parks and a more urban landscape around it just west of Downtown. So much of its course west of downtown Houston it is really just a large creek passing through attractive forested land, making it a very pleasant and well-used recreational waterway, that is also managed for flood control. This is not an apples to oranges comparison at all.
First: You said "I honestly can't imagine a scenario where anyone in any branch of public service would care or even have such a responsibility." Well, I provided you a scenario. Not an apples to oranges scenario, but a scenario of a stream attractive enough to be used for recreation, small enough that logjams could present a flood issue, and managed by a government agency that does remove trees when they fall in it.
Second: You said "I don't see flooding as an issue at all, since the biggest, densest, nastiest log jams I've seen don't raise the river enough to notice (in fact, as soon as a tree falls and obstructs flow, the river simply scours a hole underneath it), but in any case, the very idea of "improving flow" has, for decades now, been seen as old-fashioned and counter-productive on any river small enough for logjams to be a consideration." The US Army Corps of Engineers and Harris County Flood Control District seem to disagree with you, at least in this instance, and I am not inclined to debate the wisdom of their management plan with you, my only point was that the thing you said you "can't imagine" occuring, occurs. How often it occurs is up for debate, but I doubt that buffalo bayou and the other streams of Harris County are so exceptional as to be singular. PJC did not mention a particular body of water he was talking about, he seemed to be merely talking about the issue in general, so I merely mentioned this as a possible course of action. Since 81% of the US population lives in urban areas and it is likely that a water body an urban dweller uses regularly (and I did suggest this course of action only for a water body he uses regularly) is going to be fairly close to that urban area, it's not that much of a stretch that such a body of water might be used recreationally as well as managed for flood control.
First Need Purifier
2-3 Canoe/Kayak Trailer
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