WASHINGTON - U.S. construction spending was flat overall in October at $910.8 billion despite the biggest surge in homebuilding in more than a decade, the Commerce Department said on Tuesday in a report that sharply revised the prior month's data.

Instead of rising by 0.8 percent as it said a month ago, the Commerce Department now says September construction spending slumped by 1.6 percent, its sharpest monthly fall since a 2.8 percent decline last January. The department said the last month in which total construction spending rose was in April, when it was up 0.5 percent.

Economists surveyed by Reuters had forecast October construction spending would decline by 0.5 percent.

Spending on homebuilding was up 4.4 percent in October, more than recovering from a 2 percent dip in September. It was the biggest monthly gain in private residential spending since a matching 4.4 percent rise in March 1998.

Spending on public construction projects was down 0.4 percent in October after rising 0.9 percent in September. Spending on healthcare, highways and streets and power projects all was off from September, the department reported.

(Reporting by Glenn Somerville, editing by Andrea Ricci)