The river valley is low-lying and narrow, and the subsequent fogs are notable in their effect, some created by smelter fumes in earlier years.

[2][3][4] In April 1906, a significant flooding occurred in Queenstown and the southern part of the town due to the river overflowing.

When it was in operation, the fumes from the ore smelter produced acid rain which also leached minerals from the bare Queenstown hills.

However, acid water continues to enter the river due to mine dewatering and run-off from the waste rock dumps.

Without the buffering previously provided by the alkaline tailings, the acidity in the Queen and King rivers has increased, and dissolved metal concentrations have greatly increased-to levels completely inhospitable to life.