The Gilbert Road crossing at the Salt River opens to traffic Monday as workers complete the final steps to eliminate a bottleneck that's slowed traffic since 2007.
Both directions of traffic will shift to the new low-flow crossing Monday so crews can begin restriping the road for its permanent configuration. That means drivers will still have the bottleneck, just on the new crossing instead of on the permanent bridge.
But both the bridge and low-flow crossing will open by 6 p.m. Aug. 18, restoring normal traffic flows after years of work and delays.
The northbound crossing washed out in a 2007 flood, forcing traffic to share the permanent bridge that normally carries southbound traffic. The Maricopa County Department of Transportation began building a new crossing but work halted in February 2010 as water gushed through the normally dry Salt River. Some large pipes were already set in place, said Roger Ball, a McDOT spokesman.
"When the flows begin, they bring this enormous debris with them," he said. "It's not just water. It's trees, it's boulders, it's cars, it's everything. It moved these pipes around somewhat."
The new crossing was designed to handle more water than the one that washed away four years ago.
Still, it's deemed a temporary structure.
Transportation officials have long planned for a six-lane bridge to span the river. Gilbert carries about 14,600 cars a day and it's projected to handle three times that by 2030.
Officials have estimated a $45 million cost. It would likely be funded by McDOT, Mesa and the Salt River Pima-Maricopa Indian Community.
The three governments haven't identified the specifics of the project or designed the bridge.