You can have a look at these tags: [`man_made=dyke`][1] [`waterway=flow_control`][2] and `flow_control=sluice_gate` Generally you will find information regarding `waterway`s [here in the wiki][3]. If a feature is interrupted (e.g. for a street) you can should interrupt it in OSM as well. For gates there is `barrier=gate`, maybe this can be used for your purpose. You should not judge only based on the current rendering appearance, rather try to give a precise and correct description of the feature you are going to map. [1]: http://wiki.openstreetmap.org/wiki/Tag:man_made%3Ddyke [2]: http://wiki.openstreetmap.org/wiki/Proposed_features/sluice_gate [3]: http://wiki.openstreetmap.org/wiki/Key:waterway

You can have a look at these tags: [`man_made=dyke`][1] [`waterway=flow_control`][2] and `flow_control=sluice_gate` Generally you will find information regarding `waterway`s [here in the wiki][3]. If a feature is interrupted (e.g. for a street) you can interrupt it in OSM as well. For gates there is `barrier=gate`, maybe this can be used for your purpose. You should not judge only based on the current rendering appearance, rather try to give a precise and correct description of the feature you are going to map. [1]: http://wiki.openstreetmap.org/wiki/Tag:man_made%3Ddyke [2]: http://wiki.openstreetmap.org/wiki/Proposed_features/sluice_gate [3]: http://wiki.openstreetmap.org/wiki/Key:waterway