Mr Sammy LAI says that the manhole covers were round in the early days, and they were later turned into square shape to facilitate drainage workers to open for inspection and clearance of manholes and drains.

Mr Sammy LAI says that the manhole covers were round in the early days, and they were later turned into square shape to facilitate drainage workers to open for inspection and clearance of manholes and drains.

Mr Sammy LAI says that the manhole covers were round in the early days, and they were later turned into square shape to facilitate drainage workers to open for inspection and clearance of manholes and drains.