AASHTO Journal, 30 September 2016
A new report on Oregon highway bridges by the state Department of Transportation found that ODOT would need to spend $435 million a year for the next 20 years – compared with $85 million now – to keep up with growing bridge preservation needs and a backlog of replacement projects.
The report made clear that the current revenue stream for bridge work will not allow ODOT to keep up with infrastructure needs.
“Limited funding has prevented ODOT from managing near a sustainable level, and based on current funding levels, the number of bridge preservation and replacement projects will not increase significantly,” the report said. “Oregon needs dedicated and sustainable funding that will allow ODOT to implement a comprehensive strategy to fix bridges for the long term.”
It also spelled out the economic burden that could come without enough funding to tackle bridge needs. “Worsening conditions will increase transportation user costs and hurt Oregon’s economy,” the report said. “Economic analysis has indicated that the state could forfeit 100,000 jobs and $94 billion in production by 2035 as a result of deteriorating bridges.”
The department said almost two-thirds of the state’s 2,700-plus highway bridges were built before modern earthquake design standards, and that despite targeted investments in the past decade that shored up more than 270 of them “hundreds more remain vulnerable.”
“Simply to maintain Oregon’s aging bridges in their current condition, ODOT would need to spend an estimated $240 million annually – approximately $155 million in additional funding for state highway bridges,” ODOT said in a news release.
Even the larger number of $435 million a year to tackle all preservation needs and the project backlog assumes that each bridge lasts for 100 years, with two to three major rehabilitations during its lifetime along with minor preventive maintenance.
The agency said more than half its bridges were built prior to 1970, and that 57 percent will reach the end of their design lives by 2020.
“With increased maintenance and repair, most of ODOT’s bridges can have a longer service life – but this does not hold true for a large number of bridges built during the Interstate era of the 1950s and 1960s that are still in use today,” ODOT said. “Many of those bridges were designed for loads smaller than allowed by state law since the mid-1980s, and preserving them is not cost-effective.”
Over the next 20 years, it said, about 900 state highway bridges will need to be repaired or replaced, but the agency expects to have only enough funding to address about 300. That would mean it would need to reduce truck weights on many, forcing commercial users to switch to longer routes or use more trucks to haul the same amount of cargo.
“These impacts are extremely harmful to Oregon as a heavily trade-dependent state,” it added.
The study said other consequences of not funding bridge projects more robustly would include “long delays to the traveling public associated with closures and emergency bridge repairs,” and “high costs for reactive repairs to an ever-increasing number of deteriorated bridges.”