<ARTICLE> UT
<LEGEND>
This schedule contains summary financial information extracted from balance
sheets, income statements and cash flow statements and is qualified in its
entirety by reference to such financial statements.
</LEGEND>
<MULTIPLIER> 1,000
       
                             
<PERIOD-TYPE>                   6-MOS
<FISCAL-YEAR-END>                          DEC-31-1997
<PERIOD-END>                               JUN-30-1998
<BOOK-VALUE>                                  PER-BOOK
<TOTAL-NET-UTILITY-PLANT>                    1,720,067
<OTHER-PROPERTY-AND-INVEST>                    113,831
<TOTAL-CURRENT-ASSETS>                         202,819
<TOTAL-DEFERRED-CHARGES>                       401,968
<OTHER-ASSETS>                                       0
<TOTAL-ASSETS>                               2,438,685
<COMMON>                                        94,031
<CAPITAL-SURPLUS-PAID-IN>                      358,113
<RETAINED-EARNINGS>                            272,830
<TOTAL-COMMON-STOCKHOLDERS-EQ>                 724,974
<PREFERRED-MANDATORY>                                0
<PREFERRED>                                    106,556
<LONG-TERM-DEBT-NET>                           686,227
<SHORT-TERM-NOTES>                                   0
<LONG-TERM-NOTES-PAYABLE>                       63,649
<COMMERCIAL-PAPER-OBLIGATIONS>                  52,527
<LONG-TERM-DEBT-CURRENT-PORT>                   35,167
<PREFERRED-STOCK-CURRENT>                            0
<CAPITAL-LEASE-OBLIGATIONS>                          0
<LEASES-CURRENT>                                     0
<OTHER-ITEMS-CAPITAL-AND-LIAB>                 769,585
<TOT-CAPITALIZATION-AND-LIAB>                2,438,685
<GROSS-OPERATING-REVENUE>                      459,792
<INCOME-TAX-EXPENSE>                            22,338
<OTHER-OPERATING-EXPENSES>                     360,454
<TOTAL-OPERATING-EXPENSES>                     382,792
<OPERATING-INCOME-LOSS>                         77,000
<OTHER-INCOME-NET>                               4,027
<INCOME-BEFORE-INTEREST-EXPEN>                  81,027
<TOTAL-INTEREST-EXPENSE>                        29,803
<NET-INCOME>                                    51,224
<PREFERRED-STOCK-DIVIDENDS>                      2,822
<EARNINGS-AVAILABLE-FOR-COMM>                   48,402
<COMMON-STOCK-DIVIDENDS>                        34,979
<TOTAL-INTEREST-ON-BONDS>                            0
<CASH-FLOW-OPERATIONS>                          91,054
<EPS-PRIMARY>                                     1.29
<EPS-DILUTED>                                     1.29