PINE RIDGE, S.D. (AP) — A $500 million project to pipe drinking water from the Missouri River to 50,000 rural South Dakotans is taking another step toward completion.

The Rapid City Journal reports that the Oglala Sioux tribe is requesting bids this month for a distribution system between Hisel and Allen on the Pine Ridge Reservation. The cost is estimated at up to $7 million.

The federally funded Mni Wiconi project was started in 1988 to bring drinking water to three American Indian reservations and 10 counties in rural South Dakota. The project is now more than 95 percent complete. The reservation's portion of the project should be done by late next year.

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