# Pounds Per Square Inch

A popular pocket-theorem thrown around by mainstream reporters is that if the energy contained a single 10-foot Pipeline wave could somehow be channeled into an electrical generator, the resulting wattage would light up a small town for a night.

So far, nobody’s field-tested this intriguing bit of folk science. But if you asked anyone who’s ever watched Pipeline casually throw a millpond’s worth of water over its shoulder in one elegant heave, there would be little argument that Pipeline has more raw PPSI at three feet than San Onofre has at eight.

So all things being equal why is it the same Pacific superswell that produces a Maverick’s or a Jaws, only creates six-foot slop at your local beach down in San Diego?

According to Dr. Shaw Mead of Artificial Surfing Reefs International, a New Zealand-based marine scientist and coastal engineer, the over-riding factor that makes the world’s heaviest waves so heavy is the bathymetry (the underwater landscape) leading up to the final impact zone.

“A common offshore seabed feature of gnarly wave spots is a submarine ridge that acts to ‘focus’ waves so that they break bigger and usually ‘bowlier’ than other breaks,” says Mead, who based his doctoral thesis on studying Shark Island, Pipeline and other world-class breaks.

Underwater canyons, embayments, and rock jetties are some of the coastal features that direct and compress a swell’s energy into a small area. Think of a piston compressing air and fuel into an engine cylinder. Now think of Pipeline blowing a huge cloud of spit. Same thing.

Second: Size. The bigger the swell, the more potential energy (theoretically) it contains. High swell energy translates to pure juice when it pushes over a shore with auspicious underwater bathymetry. Bigger wave, bigger boom.

Third: Sharply shoaling bottoms. Steeply pitched bottoms (a 1- to-7 rise ratio is considered optimum for “extreme” pitching waves like Pipeline or Shark Island), if sited correctly, will act as a launching ramp for the swell, giving it added punch. A fast-moving open-ocean swell that rapidly runs out of ocean will topple forward with more force than one that gradually shoals up over many miles. Need a mental picture? Visualize the reef at Teahupoo.Mead states it is rare to get the wave climate and the deep water, but even rarer for the steep reef to be orientated correctly to produce peeling, surfable waves. Hence, just like the rarity of world-class surfing breaks for normal-sized waves, big wave spots are even rarer.

Grant Washburn, a San Francisco filmmaker and notorious big-wave junkie (paddle-in only), has made a career out of studying unique behemoths like Maverick’s and Dungeons. His field data comes straight from the viewfinder and the impact zone.

To read more from the 10 Most Powerful Surf Breaks in the World check out Surfer magazine’s annual BIG Issue Vol 43 #9. Click here to subscribe or go to your local surf shop or newstand to purchase the BIG issue.