Hydraulic mining, an innovation of the mid-19th century, revolutionized the mining industry. Born during the California Gold Rush, this method employs high-pressure jets of water to dislodge rock material or move sediment. In the placer mining process, powerful water cannons blast away topsoil, exposing valuable ore deposits below. This technique is not without controversy, as it significantly alters landscapes and can cause serious environmental damage, including soil erosion and habitat destruction.

Initially praised for its efficiency in extracting gold from otherwise inaccessible places, hydraulic mining later faced legal challenges due to its environmental impact. The practice led to the clogging of rivers with sediment, impacting agriculture and water quality downstream. Today, hydraulic mining is subject to strict regulations to mitigate these effects, employed mostly in controlled environments or where rehabilitation plans are in place. This technique stands as a powerful reminder of the balance between technological advancement and environmental stewardship.