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NARRATIVE: The organization culture at the City of Gresham WWTP has had proactive leadership and 
organization that results in innovations that benefit ratepayers, as well as the larger world beyond the 
City of Gresham.  An example of this is the seven year effort to make the Gresham WWTP energy net 
zero.  The Gresham WWTP now produces more renewable energy on site than it needs to run the plant 
each year, the first plant in the Pacific Northwest to be energy net zero, and one of a handful in the U.S.   
This benefits the ratepayers, but also reduces greenhouse gas emissions and the carbon footprint.  
There are also many educational benefits - the local 5th graders now have curriculum based upon the 
Gresham WWTP Journey to Net Zero. The City of Gresham also does a lot of outreach to industry peers 
who are interested in replicating the success the Gresham WWTP has had with FOG codigestion and 
cogeneration.    

Gresham WWTP has a participatory and collaborative spirit.  An example of this is the Energy  

Committee which includes representatives from engineering, operations and maintenance who meet 
once a month to focus on continued energy conservation and energy production. This collaboration has 
resulted in a reduction of power consumption at the plant by 17 percent over the last 5 years as well as 
the plant being energy net zero since March 2015.  Plant staff receive annual energy training, and 
receive energy awareness reminders in weekly operations and maintenance meetings.  

Energy Efficiency   Since 2010, the Gresham WWTP power consumption has been reduced 17 percent 
through a combination of operational changes and equipment replacement.  In 2010, the plant Energy 
Management Team was formed and began meeting once a month to focus on energy consumption and 
the most effective ways to reduce consumption.  In 2011, the Process Improvements Project replaced 
older equipment in need of replacement with more energy efficient new equipment. Equipment 
replaced included the old digester mixing system (120 HP) with new vertical linear motion “pancake” 
mixers (10 HP) and 30 year old blowers with modern “air bearing” turbo blowers coupled with modern