TULSA, Oklahoma - A construction crew raced to finish an urgent job for Tulsa's gigantic new park, A Gathering Place.

It's work that could go unnoticed, unless you happen to drive the 21st street bridge and look down.

A flotilla of excavators has been in the river all week, with a convoy of large dump trucks.

They're digging out, trucking over and piling up a mountain of sand. They've been working around the clock since Monday.

"And probably this evening about dark we'll start to have that inflow of water hit the banks of the Gathering Place," said Jeff Stava, project manager.

With the gates at Keystone open the water is coming, and if it's a repeat of 2016, the river could be full through summer. So they're moving quickly, excavating river bed to create a larger pool for the lake.

The material that's removed creates more land for the park.

"All of that silt and sand is being used to create the topography," Stava said. "The hill behind the ONEOK boathouse is 52 feet above grade and that is all sand that's actually put in."

Elsewhere in the Gathering Place, work continues on the large wooden towers, as tall as trees on the eastern edge of the playground. The city has poured concrete on Riverside Drive down into the northern tunnels. 

work continues to catch up on tree planting that was delayed during the warmer that usual winter.

Stava said, "Nearly a hundred, a thousand trees have been planted since we started that in January so there's work going on in every corner of the park."