The Ballast Hills

  Disposing of sand ballast was a problem which grew with trade. At first, ships shed their ballast at the quays, before filling up with coals and salt. As vessels and commerce increased in volume, so too did harbour congestion, worsened all the while by the mountains of ballast. After a time, as access deteriorated for larger ships, keels and lighters had to carry sand from them to the quayside, and take coal out.