BEVERLY, Wash. -

A contractor is erecting a platform on Wanapum Dam for drilling to explore the size of the crack that was discovered Feb. 27 in a spillway pier.

While the Grant County Public Utility District decides on a repair plan, the reservoir behind the dam near Vantage remains lowered to reduce pressure.

The exposed shoreline is closed to the public. The utility says it's working with affected irrigators and making plans for fish ladders to start working by mid-April.

While the crack is being repaired, the dam is producing about half the electricity it would normally produce.