The Environmental Division of the Water Utilities Department is responsible for compliance with the Federal Clean Water Act, Safe Drinking Water Act, Aquifer Protection Permits, existing National Pollution Discharge Elimination Permits (NPDES) and the Arizona Pollution Discharge Elimination Permits (AZPDES) requirements for operation of the sanitary sewer, stormwater, water production, and wastewater treatment/discharge.  The five programs within the Environmental Division are Backflow Prevention, Pretreatment, Regulatory Compliance, Stormwater, and the Water Quality Laboratory.

The Backflow Prevention Program is responsible for administering the City of Tempe 's Backflow Prevention Program, which is a containment program as defined by state regulation, R18-4-115, and Tempe City Code.  The purpose of the Backflow program is to protect the public water supply of the city from the possibility of contamination or pollution by isolating within the user's system such contaminants or pollutants which could backflow into the public water supply, and to provide for the monitoring and enforcement of the program.  This is accomplished by inspecting service connections to ensure compliance with ordinances related to backflow, tracking the annual testing of privately-owned backflow assemblies to ensure proper operation, and investigating water quality complaints and backflow incidents.

The Pretreatment Program is responsible for complying with federal, state, and city laws and requirements affecting industrial and commercial sanitary sewer users and to also ensure that the City is complying with stormwater permit requirements.  The City, through the Pretreatment Section, issues wastewater discharge permits to industrial facilities engaged in such activities as aerospace, circuit board, semiconductor, and metal finishing operations that discharge process wastewater to the publicly-owned treatment works (POTW) as part of a source control program.   Through the Fats, Oils, and Grease (FOG) Inspection Program, commercial facilities such as restaurants, sandwich shops, and cafeterias are inspected on a routine basis to ensure that required equipment is in place and is being properly maintained. 

The Stormwater Program is responsible for compliance with the NPDES Stormwater Permit and comprised of staff from the Pretreatment Section and the Regulatory Compliance Section.  Although Tempe is located in the Sonoran Desert and only receives approximately seven inches of rainfall annually, the existing NPDES permit and soon-to-be-issued AZPDES permit require inspections of approximately 800 businesses, monitoring of rainfall events, screening of all major outfalls which discharge to the Waters of the United States, and inspections of construction site activities to ensure that track out of debris and discharge of pollutants does not occur. 

The Regulatory Compliance Program of the Environmental Division manages City-wide environmental compliance by 1) assessing the applicability of environmental laws and regulations to City facilities and operations; 2) negotiating and maintaining federal, state, and county water, wastewater, stormwater, and air quality permits required for City facilities; and, 3) ensuring compliance with environmental regulations and permits through compliance-assistance efforts for facility managers and through the use of the City’s environmental compliance management system.  The Regulatory Compliance Section also implements training and outreach programs for Tempe residents and other City departments on environmental programs and regulations.

The Water Quality Laboratory is responsible for performing water quality testing of drinking water to ensure that the City of Tempe is in compliance with all state and federal regulations such as the Safe Drinking Water Act. Analyses are also done on wastewater discharged to and from the Kyrene Water Reclamation Facility along with the Pretreatment and Stormwater programs to ensure that the standards for those permits/programs are being met. The Laboratory’s goal is to provide high quality analyses in a short amount of time. The lab is licensed by ADHS. The laboratory staff provides technical assistance for Water Treatment Plant(s) staff to improve treatment and assists other City staff on special projects as needed. Laboratory staff also addresses residents' inquiries and complaints concerning their drinking water quality.

Green Buildings and Sustainability information is available through the Transportation Division of the Public Works Department.