So they were working on fixing this but the west imposed sanctions in the 90s and stopped work.
"There is no permanent solution except building another dam,” Ansari said. A second structure, the Badush dam, was started 20km downstream, to prevent a catastrophe in the event of the Mosul dam’s failure. But work on Badush halted in the 1990s because of the pressure of sanctions, leaving it only 40% complete."
Interesting that you can find a way to blame this on the West when Saddam could just have complied with the UN (who imposed the sanctions, not the "West"), had the sactions removed, and given his people a better life.
Actually, the US wanted Saddam away just the same like they wanted Assad away. There was nothing Saddam could do except for allowing the US to take over the whole country and prosecute (and kill) him.
That's why the info about WMD was faked, both by the US and the UK. The UK was extreme, doing copy paste of the works of students from the internet. It's an interesting read.
"The Government was accused of attempting to mislead Parliament and the general public after it emerged a dossier of evidence against Saddam Hussein was largely lifted from a Californian postgraduate student's outdated thesis."
Not to mention the war in 2003 and everything afterwards, as presented by Bush (even if he hasn't personally developed the plan), it was "to bring democracy" there.
Since the US was effectively for years in charge there, since 2003, theoretically, there was certainly enough time and money to finish the second dam.
The US was trying to provide "aid" in protecting the dam in 2007 - I have no idea if it was taken on as a legitimate project or just wallpaper to say "see how we're helping".
I don't have time for fun conspiracy theories, but I'm sure lines can be traced all around construction of the dam, through the bush family, back to infrastructure, etc.
The estimated cost of finishing the second dam is much bigger than the "aid" from the link (the aid was meager $27m, split to 21 contractor), but still orders of magnitude lower that the money spent by the US only on the military in Iraq.
Therefore not surprising, from the 2007 article behind your link:
"In a report published on Tuesday, the Special Inspector General for Iraq Reconstruction (SIGIR) said US-funded "short-term solutions" had yet to significantly solve the dam's problems."
"There is no permanent solution except building another dam,” Ansari said. A second structure, the Badush dam, was started 20km downstream, to prevent a catastrophe in the event of the Mosul dam’s failure. But work on Badush halted in the 1990s because of the pressure of sanctions, leaving it only 40% complete."