dropshafts

construction workers descended the vertical dropshafts to inspect the tunnel.

the mine utilizes two main dropshafts for ore extraction.

engineers designed new dropshafts to improve the sewer system.

heavy rain flooded the drainage dropshafts yesterday.

concrete dropshafts are essential for this hydroelectric project.

safety regulations require covers for all unused dropshafts.

ventilation pipes were installed within the deep dropshafts.

the plumber cleared the debris blocking the dropshafts.

we need to measure the depth of these dropshafts.

water flows rapidly through these spillway dropshafts.

old dropshafts pose a significant risk to hikers.