How to describe wastewater aeration tanks?

I have found various descriptions/tags for watewater tanks but is there a way to describe open/uncovered aeration tanks?

Aeration tanks or pools are mostly found in Municipal Water Treatment Plants.

I assume this is for tanks for further purification of drinking water. In this case there is already a manmade = waterworks that could go around the outside boundary of the works, and any tanks inside could be marked for a reservoir. Further information of the purpose of the precise tank is probably beyond the scope of OSM, but could be included in the note or sometimes in a name.

I think this is sewage processing: http://wiki.openstreetmap.org/wiki/Tag:man_made%3Dwastewater_plant not water purification.

Sewage tends to contain a lot of nutrients which feed micro-organisms, which deplete the water of oxygen, when consuming them. This is probably about loading the sewage with oxygen, so that the micro-organisms burn off the nutrients before the water is discharged into a river.

Area:

natural=water
water=wastewater

We actually dont have good tags for all but the top level for water distribution and waste water treatment. An example might be the various types of filter beds which are obvious features in older British sewage farms.

If you have any specific knowledge it would help codify how to map these plants in detail.

Suggestions to use natural=water or landuse=reservoir are not particularly useful. Probably something like man_made=aeration_tank would be a start.

As far as I concern aeration tank is one of the functions in sewage treatment facility. Try for sewage treatment tags if possible.

Isn’t there some discussion in improving labeling for water treatment and wastewater treatment plants to allow for more detail? It would also help if thats done to have descriptions of the different structures and osm wiki tutorial on how to map these structures so those less knowledgeable about the specifics of the processes can accurately render similar to how power infrastructure has been done.