PHOENIX – Construction of Loop 303 from Happy Valley Parkway to Interstate 17 started earlier this year and already the Arizona Department of Transportation is ready to open the new interchange at Happy Valley Parkway in Peoria.

This is the latest construction milestone as work on the Loop 303, the first new freeway being built by ADOT with Proposition 400 funds, rapidly progresses towards the goal of opening to traffic in 2012.

Traffic will shift from the temporary detour built at the beginning of the year at Happy Valley Parkway and Loop 303 to its permanent path beneath the nearly-completed Loop 303 freeway bridge on Monday, December 21. This will allow drivers to use part of the new interchange linking Happy Valley Parkway with the freeway to the south.

The traffic switch will require a closure of Loop 303 in both directions between Grand Avenue and Happy Valley Parkway from 9 p.m. Friday (December 18) to 5 a.m. Monday (December 21). The Happy Valley Parkway ramp to Loop 303 will be closed.

Drivers can use alternate routes that include Lake Pleasant Parkway, 99th Avenue, Bell Road and Grand Avenue to travel beyond the Loop 303 closure.

ADOT officials say the new Loop 303 interchange includes two through lanes in each direction along Happy Valley Parkway, new traffic signals and dedicated turn lanes for traffic entering and exiting Loop 303 to the south. Eastbound Happy Valley Parkway will be narrowed to one lane until late December while crews finish work in the area.

The Loop 303 ramps for future travel to and from the north and east will remain closed until completion of the freeway.

Photo taken in early November shows work at the Loop 303 interchange. When the Loop 303 is completed, the two bridge decks in the photo will be freeway lanes that move traffic over Happy Valley Parkway.