SWG Engineering of Weslaco alleged in a lawsuit last month that the city of Donna fired it without good cause this summer and now owes the firm almost $4.5 million for work it performed on the city’s wastewater treatment plant. 

Donna hired SWG in 2022 to design additions and upgrades to its wastewater treatment plant as part of an estimated $38.5 million overhaul.

Donna expects its wastewater flow at the current treatment plant to exceed capacity by the summer 2028, and the facility has remained one of the city’s top priorities in recent years.

SWG Engineering initially estimated its services for the plant would cost a little over $4.1 million, but contract amendments over the next two years grew that price to $4,462,061.25.