Despite Seattle's troubled streetcar project being millions over budget, Mayor Jenny Durkan is recommending the city move forward with the project. 

The Center City Connector project is now estimated at $286 million, up from the last estimate of $252 in August, and well above the original budget of $143.2 million. 

In a memo to the city council, Mayor Durkan wrote, "It is clear now that the previous SDOT management in the last administration had failed to do the proper due diligence to account for all the costs. As a result, this project was not set up for future long-term financial success, including with the Federal Transit Administration (which does its own separate review of the project." 

Mayor Durkan notes that she is now confident the city understands the "true costs of this project." 

The original budget for the project in late 2016 was estimated at $143.2 million. In late 2016, that estimate rose to $177 million. In March 2018, the estimated cost of the project grew to approximately $197 million. It continued to balloon from there.

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In addition to the rising costs of the project itself, a significant difference in the estimated annual operating and maintenance costs were discovered. Depending on revenue and contributions from Sound Transit and King County Metro, operating costs will be somewhere between $18 million and $19 million; $2 million to $4 million higher than originally anticipated. 

Complicating the issue further, a review of the project released by the mayor's office found the new streetcars may be too big for the city's existing tracks. The review found the new streetcars were nine feet longer and 20,000 pounds heavier than the current streetcars, and would swing wider and have problems navigating corners.

An engineering analysis on the integration of the proposed new streetcar vehicles with existing and future rail lines found that modifications would cost up to $17.4 million. 

Mayor Durkan notes that the total leaves the city with a capital cost difference of $88 million more compared with the budget passed in November 2017 - before she took office. 

RELATED: Seattle streetcar project more than $100 million over original budget

Durkan says the review was a "critical step to building the confidence" of the FTA. She says she will continue working with Congress to ensure Seattle gets a $75 million FTA grant to help build the project. 

If completed, the Connector, would fill in the gap between the existing South Lake Union and First Hill streetcar lines.

The Downtown Seattle Association applauded the decision by Mayor Durkan, pointing out it is the only high-capacity rail line planned for downtown Seattle until Sound Transit's light rail system is built out further. 

“Seattle has been one of the fastest growing cities in the country over the last decade, and downtown is the fastest growing neighborhood in Seattle. Our job and population growth continue to outpace projections,” said DSA President and CEO Jon Scholes. “As we enter this Period of Maximum Constraint, we need to use our limited right-of-way more efficiently to keep everyone moving. For more than 100 years streetcars have been reliable and efficient ways for people to move within dense urban environments. We have two lines today that when connected will give people a frequent and dependable way to access the city’s most popular destinations and densest employment center. With current and projected growth, we need to get this line constructed and operating. We appreciate the Mayor taking a careful look at this and look forward to working with her and other key stakeholders to move it forward.”