Carmel Environmental Champion
A TRIBUTE TO JOHN DUFFY’S
ENVIRONMENTAL ACCOMPLISHMENTS
April 2025
John Duffy has served as director of Carmel Utilities since 1992. Carmel Utilities operates water and wastewater treatment facilities to serve a population of about 100,000. It also manages Carmel’s Household Hazardous Waste facility and the curbside trash and recycling program for approximately 32,000 households.
During his tenure, John implemented solar and a wide range of energy efficiency and conservation measures to improve operations, save tax dollars and reduce environmental impact. John also serves on Carmel’s Climate Action Advisory Committee.
His leadership is a testament to the power of city employees in building a more sustainable and resilient community. His commitment to saving energy and tax dollars serves as a model for utilities in Indiana.
We want to extend our heartfelt gratitude to John for his outstanding contributions to Carmel’s environmental sustainability and resilience, and Carmel’s climate action plan. His actions make our community and the world a better place.
Here are some key environmental accomplishments:
CLEAN SOLAR POWER OFFSETS DIRTY GRID ELECTRICITY
-Installed solar arrays in 2020 to power the 106th St Water Plant and the Hazel Dell Wastewater Treatment Plant, and installed another solar array in 2024 at the Shelborne Water Distribution Facility.
Combined (~1.25 MW), these three arrays generate approximately 1,780,143 kW-h/yr with a cumulative environmental impact of 2400 trees saved, 200 fewer cars on the road, or 925 tons of CO2 saved annually.
ENERGY CAPTURE OF BIOGAS
Methane-rich biogas produced from wastewater treatment is typically vented & flared; that’s a lot of wasted energy. Carmel’s biogas recovery system utilizes approx. 60% of the methane to heat the boilers for the biosolids process as well as heat a maintenance building. Capturing the energy content of the biogas saves the wastewater treatment facility approx. 450M BTUs/day and over $4,000/month in energy costs.
OTHER INITIATIVES AT WATER & WASTEWATER PLANTS
-Implemented extensive energy efficient lighting upgrades and many process improvements.
-Implemented the biopasture system to convert biosolid waste into fertilizer and integrated biological phosphorus removal to extract phosphorus from effluent, making it plant-available for improved fertilization.
CITYWIDE TRASH & RECYCLING
-Implemented a city-wide curbside trash and recycling program in 2012 that allows up to 3 bins per residence for a flat monthly service fee. The negotiated contract saved residents money as there was a wide range of pricing among the different companies and even within the same company. Also, contracting with one company reduced the number of garbage and recycling trucks crisscrossing the city resulting in less wear and tear on our roads as well as fuel savings.
Prior to Carmel’s citywide curbside trash & recycling program, households contracted on their own for trash collection which resulted in a very inefficient system with at least three companies (Republic, Ray’s, and Waste Management) serving Carmel. This meant that at least 6 trash and recycling trucks crisscrossed the city every week. Thanks to the citywide program, the number of trucks have been reduced from 6 to 2.
PUBLIC EDUCATION
John oversees ongoing community education efforts on conserving water usage, irrigation and also to improve recycling.
Carmel Utilities hosts two Carmel Citizens Utility Academies (a 7-week series) events every year. Participants learn how to be better consumers and recyclers, how to conserve water and protect the watershed, how to prevent interference with sewer treatment, and how to be better stewards of the environment.
Carmel Utilities also hosts several tours and educational sessions at the Water Plant and Wastewater Plant each year for several school/scout/youth groups.
Over the years, Carmel Utilities has hosted several Earth Day events at the wastewater treatment plant that were well attended and educational.
John appointed an employee to sit on the Carmel Employee Sustainability Committee, and added a second employee into the role of “Public Relations & Education Manager” to help with educating the public on water conservation and sustainability initiatives, such as decreasing water usage during irrigation months.
AWARDS & RECOGNITION
– John received the Ivan H. Brinegar award in 2024
– Carmel received the Indiana Water Environment Association award in 2021 for resource recovery, energy conservation and efficiency actions at its wastewater treatment plant, including lighting upgrades, solar, and a significant leak repair of aeration tank underground blower lines.
CONGRATS ON YOUR RETIREMENT, JOHN!
John is retiring after 32 years of service. Carmel Green Initiative looks forward to working with the incoming director.