Greene County News Report
FAIRBORN – The City of Fairborn received more than seven inches of rainfall throughout the days that make up June, the highest amount in one months’ time in the past five years. The second highest amount occurred in May 2011 with more than five inches. With the 2011 rain event, the Water Reclamation Center treated 245 million gallons of wastewater; however, in June 2015, the plant only treated 145 million gallons. Although more rain fell in June 2015 in comparison to May 2011, more water was treated during the rain event that occured four years ago.
The studies completed by the Water and Sewer Division can explain what actually happens with the rainwater.
During a rain event, a large amount of storm water, also known as Inflow and Infiltration (I&I), can enter the sanitary sewer lines through leaky manholes, cracked pipes and other openings and treated as if it was wastewater. Rain water does not require any type of treatment. However when the rain water gets into the wastewater lines, it adds work to plant operations.
The City of Fairborn has more than 150 miles of underground pipe that conveys wastewater. Utilities Superintendent Karen Hawkins stated that as part of their annual capital improvement plan, the division conducts studies to determine the water carrying capacity of the lines directing water to the Water Reclamation Center. These studies, which utilize televiewing, computer modeling and flow metering are also able to find areas where I&I occur and determine the repairs needed to allow the system to perform at optimal levels.
She added that the studies were needed to know how to plan for future growth, investigate capacity concerns, and determine best remedy for known issues. These studies allow the division to plan for repairs that can be scheduled for the following year, and prioritize those concerns that need to be addressed immediately.
Some of the pipes being replaced by conventional digging methods fall apart upon removal. Others receive “sewer lining,” which is similar to placing a pipe within a pipe. This process doubles the life expectancy of a pipe, allowing a 50-year pipe to last closer to 100 years.
“I think we have a fairly aggressive program toward sewer infrastructure renewal,” Hawkins said. “We are renewing existing infrastructure, while not having to build new pipe for additional conveyance, and not treating water that doesn’t need to be treated.”
As a result of the studies, repairs are made that renew the life of a pipe, which reduces the treatment of I&I, the potential for wastewater backups in addition to the chance for a line to collapse. The Water Reclamation Center recovers more quickly after a rain event, as less rain water and groundwater infiltrate the system. These studies and subsequent repairs now may lead to cost savings in the future for treatment of sewer water, according to the city.