San Diego Gas & Electric Co. v. Superior Court

• Decision Date: 22 August 1996
• Docket Number: No. S045854,S045854
• Court: California Supreme Court
• Parties: , 920 P.2d 669, 65 USLW 2192, Util. L. Rep. P 26,574, 96 Cal. Daily Op. Serv. 6288, 96 Daily Journal D.A.R. 10,287 SAN DIEGO GAS AND ELECTRIC COMPANY, Petitioner, v. The SUPERIOR COURT of Orange County, Respondent; Martin COVALT et al., Real Parties in Interest.

Page 724

55 Cal.Rptr.2d 724

13 Cal.4th 893, 920 P.2d 669, 65 USLW 2192,

Util. L. Rep. P 26,574,

96 Cal. Daily Op. Serv. 6288,

96 Daily Journal D.A.R. 10,287

SAN DIEGO GAS AND ELECTRIC COMPANY, Petitioner, v. The SUPERIOR COURT of Orange County, Respondent;

Martin COVALT et al., Real Parties in Interest.

No. S045854.

Supreme Court of California.

Aug. 22, 1996.

Palmieri, Tyler, Wiener, Wilhelm & Waldron, Frank C. Rothrock, Gary C. Weisberg, Irvine, Smith, Helms, Mulliss & Moore, William L. Young, San Rafael, O'Connor, Cohn, Dillon & Barr, Duncan Barr and Joel C. Lamp, San Francisco, for Petitioner.

Fred J. Hiestand, Sacramento, Catherine I. Hanson, San Francisco, Gregory M. Abrams, Kirk B. Johnson, Michael L. Ile, Chicago, IL, Martin S. Kaufman, Torrance, J. Michael Reidenbach, San Francisco, John Stuart Tinker, Rosemead, Horvitz & Levy, Ellis J. Horvitz, Frederic D. Cohen, Julie L. Woods, Encino, Spiegel & McDiarmid, Daniel I. Davidson, Scott H. Strauss, Washington, DC, De Cuir & Somach and David S. Kaplan, Sacramento, as Amici Curiae on behalf of Petitioner.

No appearance for Respondent.

Casey, Gerry, Casey, Westbrook, Reed & Schenk, Frederick Schenk, San Diego, Schroeter, Goldmark & Bender, Michael E. Withey, Seattle, WA, Robinson & Phillips and Mark R. Robinson, Tulsa, OK, for Real Parties in Interest.

Leslie Brueckner, La Jolla, Wylie A. Aitken, Annee Della Donna, Santa Ana, Miller, Starr & Regalia, Edmund L. Regalia and Arthur F. Coon, Oakland, as Amici Curiae on behalf of Real Parties in Interest.

MOSK, Justice.

Section 1759 of the Public Utilities Code ¹ declares that no court except this Supreme Court has jurisdiction to review any order or decision of the Public Utilities Commission (hereafter the commission) or to interfere with the commission in the performance of its duties. Section 2106, however, authorizes an action in superior court for damages caused by any unlawful act of a public utility. In Waters v. Pacific Telephone Co. (1974) 12 Cal.3d 1, 4, 114 Cal.Rptr. 753, 523 P.2d 1161, this court held that "in order to resolve the potential conflict between sections 1759 and 2106, the latter section must be construed as limited to those situations in which an award of damages would not hinder or frustrate the commission's declared supervisory and regulatory policies." We granted review in this case to determine whether section 1759 as construed in Waters bars a superior court action for property damage allegedly caused by the electric and magnetic fields arising from powerlines owned and operated by a public utility. We shall conclude that such an action would impermissibly interfere with a broad regulatory policy of the commission on this subject, and hence is barred by section 1759 as construed in Waters. We therefore affirm the judgment of the Court of Appeal so holding.

BACKGROUND

"Although 'electric and magnetic fields' may sound mysterious or ominous to some people, scientists have had a good understanding of them since the nineteenth century." (U.S. Cong., Office of Technology Assessment, Biological Effects of Power Frequency Electric and Magnetic Fields (1989) p. 4 (hereafter OTA Report).) ² To begin with, "Electric and magnetic fields arise from many natural sources. They appear throughout nature and in all living things." (OTA Rep., supra, at p. 4.) The Earth has a strong magnetic field arising from the rotation of its inner core. Atmospheric forces cause large electric fields at the Earth's surface during thunderstorm activity. Certain minerals in the Earth's crust, particularly iron and its compounds, have magnetic properties and give rise to magnetic fields. And at the human level, the body itself is a strong source of internal electric fields: "all cells in the body maintain large natural electric fields across their outer membranes. These naturally occurring fields are at least 100 times more intense than those that can be induced by exposure to common power-frequency fields." (Id. at p. 1.) Indeed, this phenomenon is essential to life: "cells, especially those in the nervous system, make use of complex electrochemical processes in their normal function." (Id. at p. 2.) ³

Since the development of commercial and domestic uses of electricity in the last century, many manmade sources of electric and magnetic fields have been added to the foregoing natural sources. They arise primarily from the electric power systems that generate and deliver electricity to factory, office, and home, and from the machinery, appliances, and lighting that electricity operates. The scientific explanation for all electric and magnetic fields, however, is the same.

Every constituent of matter has an electric charge, which is either positive or negative. Charges that are alike (two positive or two negative charges) repel each other, while opposite charges (one positive and one negative charge) attract; this is the electric force. The electric force acts along a line between the two charges, and its strength is inversely proportional to the square of the distance between them: e.g., if the distance between the two charges is doubled, the force of attraction or repulsion becomes weaker by a factor of four, decreasing to one-quarter of its original strength. Every charge has an electric field, which is the region of space in which the charge is capable of exerting, at a distance, an electric force of attraction or repulsion on any other charge. The electric field always begins on a positive charge and ends on a negative charge. Like the electric force, the strength of the electric field diminishes with distance from the source of the field.

When an electric charge is moving, however, it creates a different and additional force on any other charge in its vicinity, provided the second charge is also moving: this is the magnetic force. Like the electric force, the strength of the magnetic force diminishes with distance. Every moving charge likewise has a magnetic field, which is the region of space in which the charge is capable of exerting, at a distance, a magnetic force on any other moving charge. The magnetic field is more complex than the electric field: for example, the magnetic field does not have a beginning or an end, but forms closed, continuous loops of force around the source of the field. ⁴ Like the electric field, however, the strength of the magnetic field also diminishes with distance.

An electric current is a group of charges moving in the same direction through a wire or other conductor. Voltage is the difference in electric potential that causes the charges to flow through the wire; it is analogous to the pressure in a water pipe before the faucet is opened (e.g., in pounds per square inch), and is measured in volts (V) or, in the case of powerlines, in thousands of volts or kilovolts (kV). Current is the rate at which the charges flow through the wire; it is analogous to the rate at which water flows through a pipe after the faucet is opened (e.g., in gallons per minute), and is measured in amperes. The quantity of power (in watts) that a conducting wire transmits is thus the product of its voltage and its current. Power systems are designed to hold the voltage relatively constant but to meet fluctuating demand by allowing the current to rise and fall.

The strength or intensity of an electric field is proportional to its voltage, and is measured in volts per meter or in kilovolts per meter. The strength of a magnetic field is primarily proportional to its current; the most commonly used unit of measurement of the strength of a magnetic field--or more properly, of "magnetic flux density"--is the gauss. Because the gauss is a large unit, such fields are often measured in thousandths of a gauss or milligauss (mG). ⁵

Electric fields are affected by objects in the environment, especially objects that conduct electricity: some of the field lines will end on charges in the object. For example, buildings, tall fences, and even trees can partially block electric fields arising from nearby powerlines. ⁶ Magnetic fields, by contrast, pass through most objects and can be blocked only by special shielding materials.

Electric and magnetic fields affect conducting objects in the environment by the dual processes of electric and magnetic induction. ⁷ Such fields cause charges to flow in conducting objects; the resulting currents are said to be induced by the fields. The human body is a conducting object because it contains free electric charges, largely in such fluids as the blood and the lymph. When a human body is in an electric or a magnetic field, therefore, the field induces a current in the body. Electrically induced currents and magnetically induced currents flow in different patterns in the body and the strength of each depends on a variety of factors, but each is far weaker than the body's natural currents. ⁸

Naturally occurring electric and magnetic fields, such as the Earth's magnetic field, are static. Fields arising from powerlines oscillate, because the current in powerlines does not flow steadily in one direction (direct current) but flows alternately first in one direction and then in the other (alternating current). In the United States and Canada, the flow of current in electric powerlines reverses direction 60 times each second: the power is therefore said to have a frequency of 60 cycles per second, or 60 hertz (Hz). In turn, this oscillation causes the electric and magnetic fields arising from the powerlines to likewise reverse their direction 60 times each second; they are therefore said to be 60-hertz fields or power-frequency fields.

Sixty-hertz fields are also called extremely low-frequency fields, for the following reason. Such fields are only one form of the energy known as electromagnetic radiation. That energy, which is both natural and manmade in origin, has a wide variety of effects on matter depending on its frequency: the higher the frequency,...