<ARTICLE>  UT
<MULTIPLIER> 1,000
                                
<PERIOD-TYPE>                      6-MOS
<FISCAL-YEAR-END>                      Dec-31-1999
<PERIOD-END>                           Jun-30-1999
<BOOK-VALUE>                             PER-BOOK
<TOTAL-NET-UTILITY-PLANT>               2,312,161
<OTHER-PROPERTY-AND-INVEST>               370,687
<TOTAL-CURRENT-ASSETS>                    169,869
<TOTAL-DEFERRED-CHARGES>                  170,499
<OTHER-ASSETS>                                  0
<TOTAL-ASSETS>                          3,023,216
<COMMON>                                  449,697
<CAPITAL-SURPLUS-PAID-IN>                  (1,668)
<RETAINED-EARNINGS>                       427,449
<TOTAL-COMMON-STOCKHOLDERS-EQ>            878,043
<PREFERRED-MANDATORY>                          62
<PREFERRED>                                89,000
<LONG-TERM-DEBT-NET>                      697,423
<SHORT-TERM-NOTES>                         14,748
<LONG-TERM-NOTES-PAYABLE>                       0
<COMMERCIAL-PAPER-OBLIGATIONS>             94,900
<LONG-TERM-DEBT-CURRENT-PORT>             190,441
<PREFERRED-STOCK-CURRENT>                       0
<CAPITAL-LEASE-OBLIGATIONS>                     0
<LEASES-CURRENT>                                0
<OTHER-ITEMS-CAPITAL-AND-LIAB>          1,061,164
<TOT-CAPITALIZATION-AND-LIAB>           3,023,216
<GROSS-OPERATING-REVENUE>                 407,681
<INCOME-TAX-EXPENSE>                       27,648
<OTHER-OPERATING-EXPENSES>                313,135
<TOTAL-OPERATING-EXPENSES>                340,783
<OPERATING-INCOME-LOSS>                    66,898
<OTHER-INCOME-NET>                          4,062
<INCOME-BEFORE-INTEREST-EXPEN>             70,960
<TOTAL-INTEREST-EXPENSE>                   33,939
<NET-INCOME>                               37,021
<PREFERRED-STOCK-DIVIDENDS>                 1,891
<EARNINGS-AVAILABLE-FOR-COMM>              35,130
<COMMON-STOCK-DIVIDENDS>                   51,375
<TOTAL-INTEREST-ON-BONDS>                  26,255
<CASH-FLOW-OPERATIONS>                     49,530
<EPS-BASIC>                                0.57
<EPS-DILUTED>                                0.57