South Yorkshire's tram-train scheme - the first in the UK - is an example of "how not to" manage a rail project, according to the head of a Commons committee.
Meg Hillier, chair of the Public Accounts Committee, said "unrealistic costings" went unchallenged and doubts remain over whether the pilot will improve the delivery of similar programmes.
Tram-trains were due to begin running on street tracks and railway lines between Sheffield city centre, Rotherham and Parkgate in December 2015, but the work is at least two-and-a-half years behind schedule.
It is intended to be a pilot scheme to test the concept for possible wider roll-out across the UK to reinvigorate under-used rail lines, improve access to city centres and release capacity at mainline stations.
Modification of the national rail network is part-funded by the Government and managed by Network Rail.
The latter's work to modify the rail network in South Yorkshire will cost £75.1 million compared with an initial estimate of £15 million when the scheme was first approved in 2012.
The PAC compared the project to Network Rail's delayed and over-budget electrification of the Great Western rail line.
It recommended the government-owned company improve its ability to produce realistic cost estimates and ensure it makes appropriate allowances for risk and uncertainty.
Ms Hillier said: "This project promised great benefits for passengers and, importantly, a potential model for similar schemes in cities such as Manchester, Cardiff and Glasgow.
"Instead the reality is another rail project with all the makings of a 'how not to' seminar for senior civil servants.
"This pilot was trialling technology new to the UK, yet neither Network Rail nor the Department for Transport properly considered the high level of risk and uncertainty."
Ms Hillier noted that "not for the first time" the PAC heard evidence intended to reassure Parliament and the public that lessons learned would ensure the failings identified would not arise again.
She added: "We will be expecting Government to back this up with a meaningful review of the way it manages such projects."
Rob McIntosh, route managing director at Network Rail, said: "I welcome the findings of the Public Accounts Committee following the hearing in October.
"Tram train is an ambitious pilot, a UK first, and as such this project has brought with it many complex challenges.
"We acknowledge and accept the points raised and recommendations made by the committee and good progress is being made towards implementing these.
"Despite these challenges, the tram train project is now moving into the final phases of construction, with the infrastructure on course to be completed in summer 2018 meaning passengers will soon be able to reap the benefits of improved travel choices in South Yorkshire."