Updated April 5, 1:15 p.m.: The April 5-8 road closure has been canceled due to weather, officials said. The scheduled closure will take place next weekend instead. Original post: Northbound SH 121 north of the Dallas/Fort Worth International Airport will fully close for drainage work this weekend, April 5-8. This will be the first of two weekends needed to complete the drainage as part of the I-635/SH 121 interchange project, according to a Northgate Constructors news statement. Traffic will be detoured to the northbound SH 121 frontage road. In addition to the northbound SH 121 closure, the northbound SH 121 off ramp to FM 2499 will be closed. Traffic will be detoured to Bass Pro Drive in Grapevine. The westbound I-635 off ramp to northbound SH 121/FM 2499 will also be closed. Traffic here will again be detoured to Bass Pro. The $370 million Texas Department of Transportation project includes rebuilding and widening SH 121 north of the DFW Airport to accommodate new interchanges for SH 121 at I-635 and FM 2499. The Bass Pro bridge in Grapevine will also be widened to six lanes and reconstructed along with the frontage roads. The project is expected to be complete in 2022. Construction crews anticipate closing north and southbound SH 121 at Bass Pro to complete the drainage work next weekend, April 12-15, weather permitting.