This tag is now abandoned and its use on new object is strongly discouraged.
This tag has been replaced by waterway=canal + usage=spillway + intermittent=yes introduced with the new hydropower tagging scheme.
Do not, however, attempt to automatically change occurrences of waterway=spillway. Content of this page is not up to date and kept for archive purposes
|waterway = spillway
|A structure allowing the controlled release of water from a waterbody (reservoir, canal, river)
|Used on these elements
|Tools for this tag
A structure which allows the release of water from a water body, either under controlled circumstances or as a means of ensuring that water levels do not overtop and destroy containing structures (dams, levees). Spillways will normally be free of water.
Spillways may be in regular use or designed only to be used in emergencies.
How to map
- Smaller spillways, or those parts which are within the dam structure, can be drawn as a way and tagged with waterway=spillway.
- Larger ones can be drawn as an area and tagged with waterway=spillway,area=yes.
The spillway should connect to the water body which it drains and to the downstream outlet.
Wikipedia mentions different types of spillways, use spillway:type=* to describe these.
- waterway=dam - Spillways will most usually be mapped in association with dams
- natural=water + water=reservoir - Water area impounded behind.
- power=generator + generator:source=hydro - A spillway is often associated with hydropower stations.