CDM planned, designed, and oversaw construction of Waterbury's wastewater collection and treatment improvements, including a nutrient removal facility. Waterbury was charged to meet stricter effluent limits, control combined sewer overflows, mitigate odors, and address future flow needs. CDM's nutrient removal facilities design provides nitrification/denitrificiation for average flows of 27 mgd and peak flows of 50 mgd. Ultraviolet disinfection of these flows protects the Naugatuck River from the potential toxicity of chlorine disinfection. The facility also provides high-rate primary treatment and sodium hypochlorite disinfection of peak storm flows up to 83 mgd, eliminating untreated overflows to the river. Preliminary treatment and solids handling facilities are enclosed for odor control.