In addition, he said, the city is limited by state law on the amount of long-term bond debt it can hold.
Due to the road's under-utilization, the bond debt was downgraded in 2006.
The Panic of 1873 decimated the state's property tax revenue, and the state defaulted on its bond debt in 1875.
The action affects $4.7 billion in bond debt.
After that, the state would be mandated to pay down bond debt, easing the burden on future years.
But the county arranged to pay for the projects with bond debt, leading to $134 million in interest over the 24-year life of the bonds.
"What we will be doing," he said, "is increasing by 12.5 percent the amount of bond debt."
In a scheme that Congress rejected last week, the government would have borne the entire burden of the bond debt.
The county faces an Aug. 10 deadline to cover $1 billion in bond debt.
Bonneville has been repaying its bond debt on the plants for several years.
