Geologists have warned the city of Long Beach, Calif, (pop. 303,000) that if it does not do something fast, most of its harbor district, centering on the powerhouse of the Southern California Edison Co., will sink far below sea level.
In the '30s Long Beach rejoiced to find that it was sitting on top of the Wilmington oilfield, the richest in California, which has yielded $1.25 billion in 21 years. The town, on Los Angeles' southern edge, grew black with close-standing derricks and loud with never-sleeping pumps, but no one objected much.
Down, Down. Then, inch by inch, a snake crept into this oily Eden. Surveyors checking their lines during construction of a Navy drydock in 1941, noticed that the ground had sunk a little. Long Beach sages, only slightly alarmed, suggested various causes. It was an earthquake, maybe, or the result of dredging and filling in the harbor area. Few liked to mention the obvious conclusion: that the sinking of Long Beach was caused by extraction of the oil that was making the city rich.
Up flowed the oil and down sank the city. Soon the Navy, Ford Motor Co., the power company and the oil producers themselves were building costly levees to keep the salt sea away from their doors. As the sinking continued, one or two feet each year, the earth began to move sideways. Pipes broke and gushed water, oil or sewage. Pavements cracked. Bridges had to be rebuilt to keep them above the water. Such work has cost so far about $90 million.
At last the threatened city looked its enemy in the face. The geologists' reports left no doubt: the Wilmington oil sands, more than 1,000 ft. thick, have no strong rock over them. When the oil flowed out, the sands shrank slowly, and the surface sank, forming a great bowl, 24 ft. deep and more than 20 sq. mi. in area, that now reaches from the business center of Long Beach to the boundary of Los Angeles.
The industrial harbor district is laced with dikes and retaining walls to keep the sea off the land. The Ford plant and the power station are protected by levees 20 ft. high. If nothing is done to stop it, says Geologist Frank S. Hudson, the sinking will continue until the center of the depression has sunk 72 ft. below high-water mark. If this happens, the harbor department alone will have to spend $60 million on subsidence remedies.
Reversing Sea Water. Geologists believe that Long Beach has two possible recourses, both expensive. It can stop oil production and thus keep the ground from sinking as much as it would if all oil were removed. This measure would be unpopular, and probably impossible.
The other alternative is to pump sea water down abandoned wells under high pressure to replace the oil in the sands before they collapse. Something like 900,000 bbl. per day will be needed, and the total cost is something that no one likes to think about (the pumps alone might cost $50 million). After three years of pumping, Long Beach might stop sinking. The land would never rise again, no matter how much water is forced into the sands. But pipes would stop breaking, pavements would stop cracking and dikes would not have to be raised every year or so.