ftcat (2021-02-26 06:51:03+00:00): Hi OttoR,

I don't want to start a fight but I find tagging of reservoirs with a multipolygon works well and is less confusing than having overlapping ways that have to be separated out when you try to edit the tags and intend to continue in this way. If the road lay out changes and no longer follows the crest of the dam you simply remove the road tag from the dam draw the new way for the road and tag it as such, editing done.

You are making assumptions that there are pipes through the walls of these dams, in fact you are making many many assumptions when mapping in this area. The dam walls are earthen with a compacted clay core to prevent water seepage through them but no earthen dam is 100% water tight and there will always be some seepage this gives rise to the appearance of water on the downstream side of the wall. For overflow of the dam at full supply level there may be a weir, as is the case with the Mwomboshi Dam, or more often a lower section or spillway is to the one end or sometimes both ends of the wall to allow the water to flow at full supply so technically the river course will be over the spillway. The roads on these dams generally run on top of the dam very rarely behind the dam, this is because the seepage makes it boggy, the road will even run down into the spillway and cross over there. Obviously where there is a weir as a spillway the road will not travel along the crest of the wall unless a bridge is built over the weir, but as these are mainly farm dams nobody will go to the expense of constructing a bridge.

As concerns tagging the reservoirs as seasonal, this just adds a complexity that is not necessary, rather draw the way at the high water mark and leave it at that.

Here is a link regarding the completion of the Mwomboshi Dam, https://www.lusakatimes.com/2018/11/10/mwomboshi-dam-in-chisamba-district-completed-9-months-ahead-of-schedule/, you will notice it was completed in 2018 which confirms my suspicion that the satellite imagery is around 3 to 4 years out of date. You will also notice that while the HOT project references Chibombo District this area is in fact Chisamba District and has been so since 2013, admittedly it used to be part of Chibombo District but how were remote mappers to know that.

Another assumption you are making is the number of fences and gates, particularly gates, some may be cattle grids. Also  mapping the cleared areas running along side the fences as unclassified roads, they are tracks running inside a cleared firebreak. The seasonal nature of the rains here result in it being very dry from June to November and there being a great fire risk during these times. Many of the dark black areas in the imagery are burnt areas which makes it hard to determine detail when mapping and may lead mappers to tag areas as scrub when in fact they will be a wooded area just burnt off but will be full of leaves in November, the natural  vegetation here is what is termed fire climax vegetation ie it is determined by it's resistance to periodic fires.

Regarding the classifying of roads, many many of them are just tracks and even paths that have been formed by mainly foot traffic and small ox carts and bicycles not necessarily vehicles, how many vehicles have you seen in the imagery in these rural areas? They may be used by the odd small pickup truck once in a while. They grow in width as the traffic moves to one side or the other of a wet patch or other obstruction including ant hills that may grow up in the centre of the track and so the track changes slightly over time. Wet patches will become deeper over time so the traffic will start to avoid them, or a thorn tree grows up and the the track moves to avoid it in other words their course is fluid and not a planned road. If you map these as unclassified roads the map will become a dense network of roads and basically unusable.

Just a few of my thoughts on the matter.