Ottawa County has been awarded a low-interest loan of $445,512 to be used to complete the final phase of a corrosion mitigation project in the county’s water distribution system.
The Ohio Environmental Protection Agency awarded the loan, which must be repaid over 20 years, through its Water Supply Revolving Loan Account.
The agency estimates the low-interest loan will save the county about $102,799 compared to a market-rate loan.
In addition to the EPA loan, the project is receiving a $300,000 grant from the Ohio Public Works Commission and a federal special appropriations grant of $477,000.
With the funding the county will install more than 3,000 magnesium anodes to the affected pipe to inhibit corrosion. The final phase will center on lines along Oak Harbor South East Road in Salem Township, the State Route 163 distribution main that supplies water to a tower in Danbury Township, and the remaining Lakeshore Drive main line serving customers in Erie Township. County commissioners plan to advertise for bid contracts and have the project completed next year
More than 180 miles of lines comprise the transmission and distribution system that serve the City of Port Clinton, Village of Oak Harbor, and customers in Bay, Catawba Island, Danbury, Erie, Harris, Portage, and Salem townships.
The system includes pipe of ductile iron, polyvinyl chloride, and high-density polyethylene but all of the main fittings, including hydrants and valves, on the ductile iron and PVC piping installed in 1999 were made of the cast iron.
In July, 2000, about 14 months after it went into operation, the system began leaking due to corroded bolts and during the next two years the system experienced 14 additional bolt failures due to accelerated corrosion.
After hiring an engineering firm that specializes in corrosion, county officials opted to address the problem with a cathode retrofit plan, saying it is the most effective external corrosion control method for ductile iron pipe.
Steve Arndt, a county commissioner, said several factors caused the problem.
“The ductile iron pipe industry changed its standards right after the system had been installed,” he said. “If they had been in place prior to then we would have incorporated them into the project. When we were investigating the first leaks we found the soil conditions were also a factor. We were not the only system to be affected by the changes in the design standard specifications but we were one of the largest systems installed in the country at that time.”
The county completed construction in 1999 of its $68 million regional water treatment plant and transmission and distribution system. The plant, which initially had a capacity of 6 million gallons per day, was expanded in 2005 to treat 9 million gallons a day.