As the city of Georgetown prepares to build a new freeway overpass at Northwest Boulevard, the Texas Department of Transportation plans to bolster its traffic crossing at I-35 and Williams Drive with a unique design known as a diverging diamond intersection, or DDI. The $70 million construction cost would be funded by TxDOT and the Capital Area Metropolitan Planning Organization. Construction is expected to start in late 2020 with completion anticipated in mid-2023, according to TxDOT. The project would include new bypass lanes under the Williams overpass and a new northbound frontage road on I-35 between Williams and Lakeway Drive. The intersection design would be a first for Georgetown. A DDI temporarily shifts traffic to the left side of the roadway to give drivers an easier time making left turns and improve the flow of traffic moving through the intersection. The design is meant to reduce the number of starts and stops required by drivers when traveling through traditional intersections. The city of Georgetown plans to start construction next summer on a new I-35 overpass at Northwest Boulevard just north of Williams. That project, which could take 18-24 months to finish, would need to be complete before TxDOT could start on the DDI, according to Ed Polasek, the city’s transportation planning coordinator. TxDOT has implemented DDIs in several other locations nearby. A DDI opened in 2016 in Round Rock at I-35 and University Boulevard near IKEA. In Austin a DDI opened in November at Slaughter Lane and Loop 1. TxDOT has also proposed one at I-35 and Parmer Lane.