Contractors working for the U.S. Army Corps of Engineers are installing the first pieces of the massive pumps that will empty New Orleans’ outfall canals during hurricanes.

It marks the halfway point in work on the last major construction project in the region’s upgraded flood protection system.

The Permanent Canal Closures and Pumps project, as it is officially known, is on track for completion in 2017.

The permanent pumps will take over for the temporary pumps that were put in place after the levee failures during Hurricane Katrina to empty the Orleans Avenue, 17th Street and London Avenue canals in the event of a major storm.

Crews have installed two 10-foot-tall intakes at the bottom of a hole dug 40 feet below sea level near the mouth of the Orleans Avenue Canal.

Those intakes, along with a third that will be installed in the coming days, will feed into the massive pumps that will be turned on during a storm to empty the canal, said Lt. Col. Austin Appleton, the deputy commander of the Corps’ New Orleans district.

PCCP Constructors, the firm designing and building the project for the Corps, has been working on the project for two years.

The $630 million effort is the only major construction project that is still underway as part of the $14.5 billion post-Katrina upgrade to the levees, floodwalls and pumps designed to protect Orleans, Jefferson and St. Bernard parishes from the effects of a so-called “100-year storm,” a hurricane that has a 1 percent chance of occurring in any given year.

The pumping stations are designed to pump water out of the canals while closing them to a storm surge that can be pushed in from Lake Pontchartrain.

“This is a big step, but we’ve got a lot more work left on this,” Corps spokesman Ricky Boyett said.

When complete, the Orleans Avenue Canal pumping station will be able to pump water out of the canal at a rate of 2,700 cubic feet per second.

Altogether, the three pump stations will be able to pump about 24,300 cubic feet per second, enough to fill the Mercedes-Benz Superdome in an hour and a half.

Temporary pump stations are currently in place at all three outfall canals. They can pump out about 14,000 cubic feet per second, enough to provide 100-year protection to the area.

The Corps regularly tests the interim pumps, and the tests will be stepped up to a twice-monthly schedule once hurricane season starts June 1.

Follow Jeff Adelson on Twitter, @jadelson.