Santa Cruz's West Cliff Drive Wave Motor

Who hasn't stared at the pulsing ocean and tried to imagine a way to harness all that energy and have it DO something?

One of Santa Cruz's most subtle secrets is what's left of someone who had just that kind of dream. If you are willing to walk out along West Cliff Drive, dodge the joggers, bicyclists, dog walkers and strollers, you will be suitably rewarded for your efforts. Be sure to heed the signs on your left that warn of certain death awaiting you if you climb over the fence. But, watch for the streets joining West Cliff Drive on the right hand side, and when you see Chico Street, walk back until you are opposite the stucco house at 2244 West Cliff Drive. Then, very very carefully peer over the edge and you will see a huge hole in the terrace below.

The ocean still pulses up and down at the bottom of hole and when the sunlight hits the ocean just right, the water at the bottom hole has an eerie glow as if there were a huge electric light down there. The hole is six feet in diameter and over thirty feet deep and the sea has been whumping in and out for over one hundred years.

The wave motor was a wondrous low-technology solution to a vexing 1898 problem—how to water local wagon roads during a drought year and do so cheaply. The winter of 1897-98 had been pretty dry, and as the tourists came into Santa Cruz the follow- ing spring, they were faced with clouds of choking dust as they took their scenic "drives" on the cliff beyond the lighthouse. William and Edward Armstrong offered the Santa Cruz City Council a solution to the problem—they would build a wave-driven device which would pump sea water up to the top of the cliff which could then be sprinkled on the road by the water wagon.

The Armstrong Brothers
The Armstrong brothers belonged to that genus of tinkerers and ponderers who are always trying to figure out better ways to do things. In this case the inspiration came from a highly publicized 1895 effort to install an electricity-generating wave motor on the Capitola wharf. The Capitola experiment failed to generate one smidgen of electricity and was declared a failure in 1896, but not before infecting the Armstrong brothers with the inspiration to build a better motor.

After studying the history of wave motors and examining many sets of plans, the Armstrongs concluded that most motors failed for two reasons: 1) the motors were usually placed out on the open ocean where, over time, they were destroyed by the very force they were attempting to harness; 2) most of the motors had too many moving parts and were just too complex. The Armstrong solution has the smell of genius about it—put a simple machine inside the coastal cliff. Let the rock protect the device.

Author's note: OK, the next part of this story may read like something out of Popular Mechanics, but bear with me for a moment, and see if you don't agree that the Armstrongs were very clever guys.

The Motor
After experimenting with a model motor made from a coal oil can and a wooden box, the Armstrongs then built a successful prototype out near Black Point on the east side of Santa Cruz. They began by drilling a five foot diameter hole sixteen vertical feet down into the rock, and then carving a connecting tunnel out to sea so that with each wave, sea water would surge into and partially fill the space. They then lined the rock column with a metal sleeve and placed a buoyant four hundred pound piston inside it. The float rose and fell with the wave action of the ocean. Finally, the Armstrongs placed a valve across the inside of the side-branch tunnel blocking the exit of the water when it started to go back out. The heavy float then pressed down on the trapped column of water forcing it through a pipe 125 feet into the air. When the column of water was pumped out and the piston reached the bottom of its stroke, the sea water forced open the valve and filled the column again. Connect some pipes and put up a storage tank, and you've got a sea water pump. Clever stuff.

If you wanted the pump to stop pumping, there was a barrel placed on top of the platform that, when filled with water, counterbalanced the piston and pulled it above the level of the waves. Fill the barrel and the motor stopped; unplug the barrel and let out the water, and the motor started again.

The City of Santa Cruz Buys the Idea
The city of Santa Cruz was spending $1,000 a year to pump water and sprinkle West Cliff Drive in 1897, so when the council learned of the successful motor at Black Point, they approached the Armstrongs about building one for the city somewhere on the west side. The dry winter accelerated the motor's construction, and when it was finished in early summer, 1898, this larger wave motor (the piston weighed 600 pounds) could shoot a column of water 200 feet into the air. The city reimbursed the Armstrongs the cost of construction and took over operation of the motor. Water was piped from the upper tank to secondary water tanks all along West Cliff Drive from which the water wagon filled its own tank.

When Duncan McPherson, the editor of the Sentinel, went for a drive in July, 1898, he noted that the drive on West Cliff glistened with the salt that was left behind when the sea water evaporated. He also declared, "There was no dust." For about a dozen years the wave motor and the sea salted roads were a familiar Santa Cruz landmark.

Pavement eventually put the city's water wagons out of business, and all that remains to remind us of the Armstrong brothers and their ingenuity is this hole which still pulses with the ocean's power.

Sources: Santa Cruz Sentinel articles in 1898. The Washington Post newspaper had a nice summary of the wave motor in its October 9, 1910 edition, including photograph.