Mayor Jenny Durkan ordered the City of Seattle to stop streetcar projects because of rising costs.
The Seattle Times reports the $150 million project exceeded $200 million.
Durkan released a statement on Friday, writing that she initiated an independent investigation with the city attorney of the project's management to date.
In conducting a preliminary assessment, it was discovered that the proposed project also could face a significant capital shortfall, she said.
"The City of Seattle has a critical obligation to spend taxpayer dollars wisely and an equal obligation to transparency,” said Mayor Durkan.
“There are too many questions about the true costs of this project and the risks to taxpayers, which is why we must put the brakes on this project."
Seattle went ahead with its First Avenue streetcar project earlier this year, despite the two current streetcar lines falling well below ridership expectations. The First Avenue Streetcars were expected to start using dedicated lanes in late 2020, joining the city's two existing -- but not currently connecting -- lines on First Hill and South Lake Union.
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