Conroe Central Wastewater Treatment Plant – City of Conroe

Conroe Texas

The Conroe Central Wastewater Treatment Plant (WWTP) is a $60 million greenfield plant that increases treatment capacity for one of the fastest-growing cities in the United States. Prior to the project, the City’s existing Southwest Regional WWTP was nearing 75% capacity—a threshold where the Texas Commission on Environmental Quality (TCEQ) requires that additional plant capacity be under design.

To address treatment capacity needs, continued population growth, and rising energy costs, Lockwood, Andrews & Newnam, Inc. (LAN) provided preliminary engineering, final design, and construction phase services for the Conroe Central WWTP — a new 6.0-million gallons per day (MGD) WWTP with the capacity to be expanded to 12.0-MGD. The plant is the largest capital project in the City’s history.

The major project components included a diversion structure, influent lift station, influent force main, headworks with screening and grit removal, B-Stage secondary treatment, B-Stage clarifiers, tertiary filtration, ultraviolet light (UV) disinfection, non-potable water system, effluent outfall, RAS/WAS pumping system, sludge thickening, digestion, and dewatering, complete electrical system, SCADA control system, emergency generators, administration building, maintenance building, site drainage system, and access roadways.

Additionally, the project was a hybrid design that can allow future incorporation of carbon diversion, anaerobic digestion, and gas to energy production to offset operating costs.

At a glance

New 6-MGD greenfield plant

$60 million construction cost

Largest capital project in the City’s history


Hybrid process design

Activated sludge with carbon diversion


Process design

Wastewater treatment


City of Conroe

Related Work

K 12 Education

K12 Education

Wastewater and Reuse

Wastewater Treatment