<ARTICLE> UT
<MULTIPLIER> 1,000
       
                             
<PERIOD-TYPE>                   9-MOS
<FISCAL-YEAR-END>                          DEC-31-1997
<PERIOD-END>                               SEP-30-1997
<BOOK-VALUE>                                  PER-BOOK
<TOTAL-NET-UTILITY-PLANT>                    2,896,506
<OTHER-PROPERTY-AND-INVEST>                    189,432
<TOTAL-CURRENT-ASSETS>                         373,076
<TOTAL-DEFERRED-CHARGES>                       237,543
<OTHER-ASSETS>                                       0
<TOTAL-ASSETS>                               3,696,557
<COMMON>                                        48,515
<CAPITAL-SURPLUS-PAID-IN>                      695,990
<RETAINED-EARNINGS>                            346,372
<TOTAL-COMMON-STOCKHOLDERS-EQ>               1,090,877
<PREFERRED-MANDATORY>                           77,936
<PREFERRED>                                     83,000
<LONG-TERM-DEBT-NET>                         1,057,164
<SHORT-TERM-NOTES>                             126,790
<LONG-TERM-NOTES-PAYABLE>                            0
<COMMERCIAL-PAPER-OBLIGATIONS>                  57,500
<LONG-TERM-DEBT-CURRENT-PORT>                  101,067
<PREFERRED-STOCK-CURRENT>                        2,000
<CAPITAL-LEASE-OBLIGATIONS>                          0
<LEASES-CURRENT>                                     0
<OTHER-ITEMS-CAPITAL-AND-LIAB>               1,100,223
<TOT-CAPITALIZATION-AND-LIAB>                3,696,557
<GROSS-OPERATING-REVENUE>                    1,368,972
<INCOME-TAX-EXPENSE>                            79,413
<OTHER-OPERATING-EXPENSES>                   1,073,424
<TOTAL-OPERATING-EXPENSES>                   1,152,837
<OPERATING-INCOME-LOSS>                        216,135
<OTHER-INCOME-NET>                                 725
<INCOME-BEFORE-INTEREST-EXPEN>                 216,860
<TOTAL-INTEREST-EXPENSE>                        80,526
<NET-INCOME>                                   136,334
<PREFERRED-STOCK-DIVIDENDS>                     10,230
<EARNINGS-AVAILABLE-FOR-COMM>                  126,104
<COMMON-STOCK-DIVIDENDS>                        68,406
<TOTAL-INTEREST-ON-BONDS>                            0
<CASH-FLOW-OPERATIONS>                         265,614
<EPS-PRIMARY>                                     2.60
<EPS-DILUTED>                                        0