CLEVELAND, Ohio — Officials with the city of Akron said the coronavirus epidemic might result in additional delays for a billion-dollar underground sewer project mandated by a settlement it reached with the U.S. Environmental Protection Agency.

City Public Service Director Chris Ludle wrote in a note to the U.S. and Ohio EPAs that “the pandemic has caused unforeseeable shortages in the availability of materials, equipment, and labor,” which could delay or prevent the city from finishing the project on time as required by its agreement.

Ludle’s letter, sent March 24 and filed in court Friday, is what is known as a “force majeure” notification, a legal term that pertains to an unforeseeable circumstance that affects the ability to fulfill the terms of an agreement.

U.S. District Judge John Adams signed the city’s settlement, known as a consent decree, in 2014. It requires a series of taxpayer-funded fixes to finish by 2028 to bring the city’s sewer system into compliance with the Clean Water Act and stop old sewers from overflowing into the Cuyahoga River.

The cost of the fixes is estimated to be more than $1.2 billion. The Ohio Canal Interception Tunnel, which is the most significant project outlined in the consent decree, is designed to hold more than 25 million gallons of stormwater and sewage during heavy rains.

News of a possible delay of the tunnel’s completion is just the latest in a series of setbacks for the project. The consent decree called for the city to finish the tunnel by the end of 2018. However, the city has pushed back the completion date several times and has attributed delays to the complexity of the project. The city says it remains on schedule to finish by June 30.

However, the economic effects and restrictions placed on residents and businesses by the state might mean the completion date will see further delay, the letter says.

Ohio Health Department Director Dr. Amy Action last week ordered closed all “non-essential” businesses to be closed and for residents to stay in their homes most of the time. Construction companies are exempt from that order.

In addition to the measures the state took, Ludle wrote that the city of Akron put non-essential services on hold, furloughed hundreds of workers and reduced hours for others.

He said the city received a letter from a contractor on the tunnel project on March 16 that shortages of equipment, supplies, workers and public-health requirements might cause added delays.

Other projects mandated by the consent decree may also be delayed, Ludle wrote.

“Clearly, the COVID-19 pandemic is an event that is beyond the control of the City, its agents, consultant, contractors, or any entity controlled by the city,” the letter stated.

Adams has expressed displeasure that the tunnel project has been delayed and appointed a professor to review the city’s compliance with the consent decree. The city appealed the appointment.