Brooklyn-Queens Expressway drivers, take note: A critical part of the highway will once again close to traffic for the next two weekends to allow for work meant to prolong the structure’s lifespan.

The city Department of Transportation is warning drivers to take mass transit or alternative routes during the work on the southbound part of the BQE between Adams and Washington streets in Downtown Brooklyn. The work is scheduled for Saturday, Sept. 14 at 1 a.m. to Monday, Sept. 16 at 5 a.m., and again from Saturday, Sept. 21 at 1 a.m. to Monday, Sept. 23 at 5 a.m.

Officials said workers will be installing “weigh-in-motion” technology to help the city enforce truck weight limits on the highway’s ailing triple-cantilever structure. Existing weigh-in-motion sensors on the northbound side of the triple cantilever contributed to a 64% drop in the number of overweight trucks on the structure from November 2023 — when automated enforcement began — to May 2024, compared to the previous seven months, according to the DOT.

During the second round of the impending traffic changes, the Sands Street entrance ramp to the southbound part of the highway will also be closed, the department said.

Officials have previously said they’re planning to launch the use of the sensors on the southbound side of the structure after a 90-day warning period, just as they did on the northbound side. License-plate readers on this segment of the BQE enable the city to catch scofflaw drivers who flout the 40-ton restriction on trucks.