Yankton Dam Getting $20 Million Overhaul - Siouxland News - KMEG 14 and FOX 44

Yankton Dam Getting $20 Million Overhaul

If you visit Gavins Point Dam in Yankton, South Dakota today, you'll see a much different sight than you would have just over one year ago.

Back then, during the summer of 2011, water was flowing at more than 160,000 cubic feet every second.

"That is the biggest workout, definitely, that the spillway has had," said Gavins Point Project Operations Manager Dave Becker. "No doubt about it."

Nowadays you'll see completely closed spillways, due to a $20 million rehabilitation project being paid for by a Presidential disaster declaration that came last year.

In May of 2012 ground penetrating radar was used on the spillway, but what crews didn't find was the most disturbing.

Some of the gravel underneath the structure was missing.

That loss is prompting repair crews to fill two of those holes in and check for any more damage.

"Our facilities are 55 years old, so there's that factor too," said Becker. "But it is the damage to those facilities from the flood that really got all this in motion."

And the spillway isn't the only spot getting repaired.

Crews have been working for about a month adding 40,000 tons of rock to the bank below the dam.

"We lost a lot of river bed and rock during the flood there and some of the river bed eroded as much as 12 feet deeper," said Becker.

The spillway and gravel projects should both be finished up by the middle of the next year.

Starting in the spring of 2013 the spillway gates will get a nearly complete overhaul.

That work should last about two years.

Dam officials say the public should still have access to most areas of the dam during the work.