Most people who visit Las Vegas make it a point to make the 30 mile drive on Highway 93 East to get a firsthand look at one of the true engineering marvels in the U.S. — the Hoover Dam at Lake Mead. Even though the Hoover Dam is a major tourist draw, it’s also a working dam, supplying electric power to more than 20 million people.

The dam took 5 years to construct and was dedicated by President Franklin D. Roosevelt on September 30, 1935, while 10,000 people stood in 102 degree heat to witness the historic event.

Necessity Really is the Mother of Invention

The Hoover Dam, originally (and unofficially) dubbed the Boulder Dam, was originally built to control flooding along the Colorado River and to provide electric power and water to California and the Desert Southwest. The dam project spurred tremendous growth in the region at a time when men were in desperate need of work in order to feed their families and get back on their feet after the financial and social devastation of the Great Depression.

What’s in a Name?

As Shakespeare’s Juliet famously asked “What’s in a name”? Plenty of controversy, it would seem, when it came to the Hoover Dam! As mentioned, engineers and work crews referred to it as the Boulder Dam, a name that came about because its original location on the Colorado was to be Boulder. (Surveyors led the initiative to call the dam the Boulder Canyon Dam Project, but was “nicknamed” by workers as simply “the Boulder Dam.) Later, Black Canyon was deemed a better location. Even so, workers continued to refer to it as the Boulder Dam. After much back-and-forth, as well as some political debate, the dam was given the official name — The Hoover Dam — which it bears to this day!

How Hydroelectric Power Works

The only difference between a coal-fired power plant and a hydroelectric one is the source used to spin a turbine (a propeller-like piece of equipment), which then turns a metal shaft in an electric generator, which is what actually “generates” the electricity that powers homes and businesses. In the case of the coal-fired plant, steam turns the turbine. With a hydroelectric power plant, it’s falling water. The results, however, are exactly the same!

The dam — in this case, the Hoover Dam — stores a lot of water in a reservoir behind it. Near the bottom of the dam wall is a water intake. Gravity causes the water to fall through a sluice known as a penstock inside the dam. At the end of the penstock is a turbine which is turned by the fast-moving water. The shaft from the turbine goes up into the generator, which produces the power. There are power lines connected to the generator which carry the electricity to homes and business throughout a region. The amount of power produced depends on the size of the dam. In the case of the Hoover Dam, it’s a lot!

How Efficient is Hydroelectric Power?

Hydroelectric power plants are pretty efficient. Modern hydro turbines can convert as much as 90% of the available energy into electricity. (Fossil fuel-fired plants can convert 50% of the available energy into electricity at best, and unlike water, they release harmful pollutants into the atmosphere.) Water is a naturally occurring resource, so there’s no worry about unstable prices, transportation issues or production strikes.

Nothing’s Perfect: The Drawbacks of Hydroelectric Power

One of the biggest drawbacks to hydroelectric power is that the dams that produce it are, by necessity, built in hilly or mountainous areas (one reason why you don’t see dams in a flat state like Florida). However, the fault-lines that created the topography pose a great danger to the dams themselves and to the land below them for literally thousands of years after the dam has become useless for generating power. Dam failures do occur fairly regularly, and the results are, needless to say, devastating!

Then there’s the matter of flooding land with a reservoir in order to build dams. The people living on that land are uprooted and forced to start over in another area, which is, of course, stressful and often controversial.

Finally, river conservationists note that diverting a river’s water in order to build a dam adversely affects the river’s ecosystems, leading to shortages of insects for migrating birds, for instance, and disrupting the steady flows needed by certain fish species such as salmon during their early and late-life migrations. And the temperature changes caused by diverting water are harmful to native fish, who may eventually die off and disappear from their native waters.

So while hydroelectric power is inexpensive, non-polluting, and extremely efficient, it has its problems as well, as do so many sources of power that we’ve depended on for years. The solution may lie in a combination of green alternatives such as solar and wind power. In the meantime, the future of hydroelectric power is uncertain.

If you need the services of a licensed electrician for your Southern Nevada region home or business, contact us at Penny Electric. We serve the Las Vegas area, as well as Henderson, Summerlin, Green Valley, Boulder City and surrounding Southern Nevada areas with professional electric services and honest expertise!