Favorite this☆ bh017097 Concrete test cylinders cut from diamond drill cores through completed tunnel lining, Detroit water supply system
Favorite this☆ bh016497 Core samples taken from land tunnel, Waterworks Park, Detroit water supply system
Favorite this☆ bh016496 Core samples taken from land tunnel, Waterworks Park, Detroit water supply system
Favorite this☆ bh016495 Core samples taken from land tunnel, Waterworks Park, Detroit water supply system
Favorite this☆ bh016494 Core samples taken from land tunnel, Waterworks Park, Detroit water supply system
Favorite this☆ bh016493 Core samples taken from land tunnel, Waterworks Park, Detroit water supply system
Favorite this☆ bh016492 Core samples taken from land tunnel, Waterworks Park, Detroit water supply system
