By Jim Tortolano

Although Barack Obama in 2012 made strong inroads into Republican domination of Orange County during presidential elections, only once in history has O.C. swung toward the Democrats.

That was in 1936, when Franklin Roosevelt, apostle of the New Deal, carried not only the Santa Ana Valley but also 46 of 48 states in a one-sided landslide. One important reason for the rout was the popularity of various federally-funded public works programs.

In his new book, “The New Deal in Orange County,” Charles Epting sheds some much-needed light on a largely forgotten chapter in Orange County history. Uncle Sam, through the Works Progress Administration, Public Works Administration, Civilian Conservation Corps and other “alphabet agencies,” built or rebuilt schools, parks, campgrounds, libraries, roads and much more.

Charles Epting’s new book.

Not only did those projects offer facilities and infrastructure for the growing (but still largely rural) county, they employed thousands of otherwise idled workers and helped pump money into a staggering local economy.

As Epting points out, Orange County actually got more federal funds per capita than neighboring Los Angeles and San Diego counties, largely because of three natural disasters that struck the area in the Depression era: the 1933 Long Beach earthquake, followed by a flood in 1938 and a tropical storm in 1939.

These ecological events leveled schools, inundated downtowns and smashed piers all across Orange County. Federal money was welcome to help in recovering from these disasters as much or more than the general economic malaise.

It wasn’t all “free money” from Washington, Epting tells us. A typical public works operation would see the U.S. put up 45 percent of the cost of a project, with the rest borne by local agencies in the form of taxes, bond issues or donations.

New Deal operations have left a major impact on Orange County, even now almost 80 years later. Some post offices still stand (Huntington Beach and Orange, for example), along with many buildings at Fullerton College.

Many have been converted to new uses; the city hall built by the New Deal in Santa Ana is now an office building, for example. Schools were a chief beneficiary: Anaheim and Santa Ana high schools are good examples. The original main building at Garden Grove High School, badly damaged in the quake, was replaced (mostly) by a WPA structure (the original foundation is said to remain) and now houses not only classrooms but the school’s hall of fame and museum.

While Epting is careful to steer clear of any opinions about the ultimate success of FDR’s efforts to battle the Great Depression, his research points out at least one area of irony. Newport Beach, as rock-ribbed a Republican stronghold as exists in Orange County, was the beneficiary of $1.8 million in New Deal money to dredge and develop Newport Harbor; unlike other projects, Uncle Sam put up 65 percent of the cost of this undertaking.

Anaheim High School

The idea that all those yachts and mansions exist only because of the policies of a bunch of liberal Democrats in the Beltway is one of the nicest bits of unconscious humor in this book.

“New Deal” is a useful book, nicely illustrated with black-and-white photos and illustrations. Epting’s prose is workmanlike and accessible. He’s an historian, not a poet. The book, published by The History Press ($19.95; www.historynet.com), is a slender tome, just 122 pages not counting the appendix. But it fills a big gap in “modern” Orange County history and is a welcome addition to the growing shelf of local heritage.