|Locations of manholes.|
|Group: Man made|
|Used on these elements|
|Tools for this tag|
Where pipeline themselves have not yet been discovered, it can be beneficial for future mappers to mark the locations of manholes for later uses.
manhole=* can take any values, but the following are the first set in use
- plain: manhole covers with no markings at all available
- unknown: manhole cover with unknown markings, or of unknown use. Combine with label=* when possible for later identification.
- water: maintenance access to clean water pipelines
- sewer: maintenance access to pipelines carrying wastewater (sewage)
- drain: for removing excess rainfall (storm/rain drain)
- heat: district heating maintenance holes
- cold: district cooling maintenance holes
- gas: maintenance access to gas transport pipelines
- telecom: maintenance access to pipelines containing telecommunication cables
- power: access to underground electricity wires
- other: all you can think of
Tips on surveying
Often the manhole covers themselves don't feature a description of what's below, but you'll find a marker on a nearby wall, or on a dedicated stick or ventilation shaft. On such markers you might be able to read the distance to the manhole along with a diameter of the pipeline and/or an indicator of pipeline contents; some markers feature a number suitable for the tag ref=*.
When the cast iron covers themselves read "40" or "25", it's usually just a maximum weight restriction (in tonnes).