Both directions of I-35E will be closed from 7 a.m. to 7 p.m. this Saturday, Sept. 15 for maintenance activity.

From the press release:

The right lane of southbound I-35E and ramp from Shepard Road to southbound will close at 7 a.m. that day as crews make repairs to the bridges anti-icing system and perform other maintenance activities.  Once complete on the southbound lanes, around noon, the northbound right lane and ramp from Highway 13 will close.

The lanes are scheduled to reopen by 7 p.m. Saturday.