"seamark:type"=>"gate","seamark:gate:category"=>"flood_barrage","seamark:gate:clearance_width"=>"7","seamark:gate:clearance_height"=>"999"
"seamark:type"=>"gate","seamark:gate:category"=>"flood_barrage","seamark:gate:clearance_width"=>"9","seamark:gate:clearance_height"=>"999"