Gwinnett commissioners recently approved a $331,345 contract for phase four of improvements to the heating, ventilating and air conditioning system at the Gwinnett Justice and Administration Center, 75 Langley Drive in Lawrenceville.

The contract went to the lowest of three bidders, Waters Mechanical Inc. at the Feb. 2 meeting.

This phase of the project involves replacement of the HVAC equipment and associated ductwork on the east side of the basement level and the southwest side of the second floor of the administrative side of the Gwinnett Justice and Administration Center.