The various agencies of the US government are allocated more than $1 trillion of taxpayers' money annually, and not all of that cash is spent wisely or on projects that get completed. From Donald Trump's border wall to the doomed dam, click or scroll through the most notorious unfinished projects the federal government wasted money on.

Mired in controversy from the get-go, this ill-conceived dam project on the American River near Auburn, California has swallowed up hundreds of millions of dollars of taxpayers' cash since it was first proposed back in the 1950s.

After construction began in 1968, a seismic fault was discovered beneath the site. The proposed dam was unable to withstand a major earthquake and work was halted. A redesign was submitted in 1980, and construction resumed.

The project was eventually abandoned in the late 1980s as costs skyrocketed and the environmental impact was assessed. All in all, $400 million was wasted. Since then, around $31 million has been spent on attempts to revive the project, but the uncompleted dam remains an expensive flop.

Over the past decade alone, the US military has wasted tens of billions of dollars on cancelled projects at home and abroad. From 2005 to 2012, the US Air Force embarked on a fancy IT project to streamline its logistics.

There was just one catch. The system would have ended up costing more money that it would have saved. Plus, the project would have taken at least a further 10 years to complete, and by that time the technology would have been obsolete.

Instead of streamlining logistics, the system would have ended up complicating them. Finally seeing sense, the Air Force scrapped the unfinished IT project in 2012, having spent $1.1 billion trying to get it off the ground.

Even before Donald Trump's US-Mexico border wall, presidents were looking for ways to increase borders, such as President George W Bush's 'virtual wall'. The Secure Border Initiative was a Department of Homeland Security plan to create a network of surveillance towers spanning the Mexican and Canadian borders.

Construction began in 2006 on a 53-mile stretch of the border in Arizona. Plagued with problems, the initial stage of the project went massively over budget and was beset with serious technical issues.

The towers' radar sensors couldn't even differentiate between people and falling leaves. When the Obama administration pulled the plug on the whole debacle in 2011, a total of $1.15 billion had already been spent.

The US Department of Veteran Affairs has been trying to modernize its electronic health records (EHR) system for over a decade. The latest attempts were developed from 2011 to 2016 at a cost of $1.1 billion. One by one, the projects were cancelled. In 2018, a government audit revealed the US Department of Veteran Affairs had blown $2.1 billion on a series of electronic health records (EHR) upgrades that all failed spectacularly.

However, in May 2018 the department signed a $10 billion, 10-year deal with Cerner to upgrade the EHR system. This meant the system would to move from the Department of Veteran Affairs' customized VistA platform to an off-the-shelf EHR. However, since the deal was signed the budget for the project has increased to $16.1 billion. 

Due to be ready in March 2020, the EHR project was delayed once again as it needed to go through user testing. The program was finally ready in November, but it will take until 2028 for it to be fully rolled out across all facilities. It's yet to be seen if this latest project will also be a waste of money for the US government.

One of the most ambitious US megaprojects ever, the Superconducting Super Collider (SSC) in Texas would have been America's very own particle collider, rivalling the famous particle collider at the European Organization for Nuclear Research (CERN) in Switzerland.

If it had been built, the SSC may well have beaten CERN to discover the Higgs boson 'God particle'. The SSC was first proposed in 1976 and construction began in the late 1980s. By the early 1990s, costs were spiralling out of control.

The powers that be questioned the viability of the project and whether it was worth the colossal expense. Needless to say, the shockingly over-budget SSC was cancelled in 1993. By this time, access shafts and miles of tunnels had been bored at a cost of $2.4 billion.

NASA appears to be almost as free and easy with taxpayers' money as the US military. The space agency has pumped tens of billions of dollars into failed manned spaceflight programs in recent years, the most wasteful of which has been the Constellation Program.

The program was launched in 2005 with the ultimate goal to return US astronauts to the Moon by 2020. NASA was allocated a bumper budget to develop a new spacecraft, the Orion, and several Ares rockets, and didn't waste any time spending it.

In 2009, the Obama Administration deemed the project “over budget, behind schedule, and lacking in innovation”, and shut it down, after a jaw-dropping $9 billion had been spent, though NASA has used the Orion spacecraft design for its current Space Launch System.

Yucca Mountain in Nevada was chosen to be America's principal nuclear waste repository in 1987. The megaproject was approved by Congress in 2002, and work began on the complex not long after.

The project met with intense opposition and a number of problems arose, from the unsuitable geology of the site to concerns about transporting waste. When it was confirmed that nuclear power stations could store waste on site safely over decades, politicians began to wonder if the project was even necessary.

President Obama pulled federal funding in 2011 and effectively canned the project. By then, around $15 billion had been invested, and with no real plans afoot to revive the project, the Yucca Mountain repository remains in limbo.

In 2003, the US Army launched Future Combat Systems (FCS) to a fanfare of trumpets. The most extensive military modernization program since World War II, FCS would have created a fleet of lightweight robotic ground vehicles controlled by tech-savvy combat brigades.

A great idea on paper, in reality the vehicles were vulnerable to explosive devices and just weren't suited to modern guerilla-style warfare. By 2008, the program had lost the support of the army and the government, which was turning its focus away from conventional warfare to counterterrorism.

FCS was cancelled the following year. An eye-watering $18.1 billion had already been spent, and cancellation fees paid to the contractor Boeing pushed the final bill up to $19.9 billion, though it wasn't a complete waste of money as much of the technology developed has been repurposed.

A boundary between the US and Mexico has existed since 1853. While various administrations had already installed 654 miles (1,052km) of fences and barriers to separate the nations, the controversial issue really came into the spotlight following the election of Donald Trump in 2016. Trump promised to build a wall that would reach 1,000 miles (1,609km) in length during his time in office as part of his stringent anti-immigration policy.

The wall was a prominent part of the 45th president’s manifesto, and an expensive one at that. Donald Trump said the project would cost between $8 billion and $12 billion and insisted that Mexico would be the ones to foot the bill. The project was not only overbudget, but the $15 billion eventually allocated to construction was to be financed by funds taken from counter-drug budgets and military construction funding – Mexico did not contribute a single dollar to the work.

As of January 2021, the Trump administration had installed 452 miles (727km) of wall, but only 47 miles (75.6km) of that stretch were built from scratch – the rest was reconstruction of previously existing barriers. President Biden will not be picking up from where the Trump administration left off however, having promised not to construct “another foot” of the wall while in office, although he has said he will not deconstruct any part of the existing wall. This pledge will make him the first president since George H. W. Bush not to add to the barrier and will leave this expensive US megaproject incomplete for at least another four years.

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