Why did President Bush veto the water bill even though lawmakers can count enough votes to override him?

An increasingly confrontational President Bush on Friday vetoed a bill authorizing hundreds of popular water projects even though lawmakers can count enough votes to override him.

President Bush leaves the White House Friday on his way to an event in South Carolina.
锟?br> Bush brushed aside significant objections from Capitol Hill, even from Republicans, in thwarting legislation that provides money for projects like repairing hurricane damage, restoring wetlands and preventing flooding in communities across the nation.
This level of opposition virtually assured that Bush would have a veto overridden for the first time in his presidency. He has used the veto very sparingly for most of the time he has been in office, but has made more use of it recently.
"When we override this irresponsible veto, perhaps the president will finally recognize that Congress is an equal branch of government and reconsider his many other reckless veto threats," said Senate Majority Leader Harry Reid, D-Nevada.
"More than two years after failing to respond to the devastation and destruction of Hurricane Katrina, he is refusing to fund important projects guided by the Army Corps of Engineers that are essential to protecting the people of the Gulf Coast region," Reid added.

Probably to call their bluff. He's gambling that Republicans aren't going to vote to override his veto, even if they support the project. Basically he thinks that even though they want the bill to pass, they aren't willing to go against his clear wishes in order to pass it.

Also, it may be that he just wants to register his opposition to it, even if it goes through. So that in the future, if something happens and people want to point fingers at the bill, he can say "well, I did all I could, but they forced it through anyway, it isn't my fault".

President Bush exercised his veto power and hoped that Congress will not vote for overriding his decision. It is a political gamble.

Because, the House/Senate conference committee members, added 9 billion in pork barrel spending to the bill, while it was in committee.

The house passed a 15 billion dollar Bill.
The senate passed a 14 billion dollar Bill.

Those are the projects that everyone agrees should be funded.

Not the extra 9 billion in pork barrel spending, added to the bill during conference.

Even Democrats think the bill should have been vetoed because of the additional pork added to the Bill.