In the spring of 1985 a permanent tunnel was opened, allowing water to drain out of the Spirit Lake safely. This tunnel is 11 feet ( meters) in diameter and more than miles ( kilometers) in length. The water level of Spirit Lake is now maintained at approximately 100 feet (30 meters) below the estimated overtopping level.

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In the spring of 1985 a permanent tunnel was opened, allowing water to drain out of the Spirit Lake safely. This tunnel is 11 feet ( meters) in diameter and more than miles ( kilometers) in length. The water level of Spirit Lake is now maintained at approximately 100 feet (30 meters) below the estimated overtopping level.

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