> On Oct 26, 2019, at 6:01 AM, marc marc <marc_marc_...@hotmail.com> wrote: >> >> Man_made=flood_mitigation_basin sounds good. > > that look like 2 infos into one key :s > > man_made=basin usage=flood_mitigation ?
Yes, my bad. I think that is a good solution for the basin. One big question. Something has been bothering me about the basin: So far, we have been discussing discrete structures that are contained. They have an inlet weir or spillway, and have an exit drain or giant sluice gate Leading to the drain of the system (usually back to the river). A basin seems like a good label for this structure. I am unfamiliar with other countries, but Japan makes extensive use of land inside the river levees. The levees are often spaced 20-100m away from an internal embankment, which is the normal "riverbank", where normal storms are contained. 1-3m Above this embankment are heavily used sports grounds, parks, golf courses driving school grounds, and other very well-maintained facilities that are expected To be underwater during a floo-event. No buildings or structures are allowed. Similar to these basins, the extent of the flooding is known (inside the levees) and is otherwise normally usable grounds 360+ days a year. Is the long channel formed by the levees, but almost never used except during flooding also some version of this? Is mapping the extent of the levee flooding already Mappable? If that is the case, then these currently discussed basins are *inside* the levee protection system (a large bulge with a narrow bottleneck at the spillway connecting it to the river levee - yet "part" of the raging river during flooding, just like the Riverside land. Would it be better to have a tag that is able to handle this "inside the levee" area, or just map the basins as separate objects? Would having a feature like "floodbank" be useful? Would it cover from levee to levee, or be two separate things, one for each side of the river, mapping the space between the levee and the riverbank? Would it simply be a way and put in a relation with the waterway that causes it? To a farmer or a baseball player, whether your baseball daimond is along the river or in one of the basins makes little difference when a storm is large enough to fill the river. Javbw. _______________________________________________ Tagging mailing list Tagging@openstreetmap.org https://lists.openstreetmap.org/listinfo/tagging
