<TABLE> <S> <C>
<PAGE>
<ARTICLE> UT
<LEGEND>
THIS SECTION OF THE SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED
FROM THE CONSOLIDATED FINANCIAL STATEMENTS AND IS QUALIFIED IN ITS ENTIRETY BY
REFERENCE TO SUCH FINANCIAL STATEMENTS.
</LEGEND>
<MULTIPLIER> 1,000
<S> <C>
<PERIOD-TYPE> 9-MOS
<FISCAL-YEAR-END> DEC-31-2000
<PERIOD-END> SEP-30-2000
<BOOK-VALUE> PER-BOOK
<TOTAL-NET-UTILITY-PLANT> 1,023,000
<OTHER-PROPERTY-AND-INVEST> 0
<TOTAL-CURRENT-ASSETS> 36,474
<TOTAL-DEFERRED-CHARGES> 45,198
<OTHER-ASSETS> 0
<TOTAL-ASSETS> 1,104,672
<COMMON> 85,474
<CAPITAL-SURPLUS-PAID-IN> 192,717
<RETAINED-EARNINGS> 93,589
<TOTAL-COMMON-STOCKHOLDERS-EQ> 371,780
0
0
<LONG-TERM-DEBT-NET> 436,753
<SHORT-TERM-NOTES> 0
<LONG-TERM-NOTES-PAYABLE> 0
<COMMERCIAL-PAPER-OBLIGATIONS> 28,867
<LONG-TERM-DEBT-CURRENT-PORT> 0
0
<CAPITAL-LEASE-OBLIGATIONS> 14,996
<LEASES-CURRENT> 533
<OTHER-ITEMS-CAPITAL-AND-LIAB> 251,743
<TOT-CAPITALIZATION-AND-LIAB> 1,104,672
<GROSS-OPERATING-REVENUE> 175,171
<INCOME-TAX-EXPENSE> 27,403
<OTHER-OPERATING-EXPENSES> 74,433
<TOTAL-OPERATING-EXPENSES> 101,836
<OPERATING-INCOME-LOSS> 73,335
<OTHER-INCOME-NET> 132
<INCOME-BEFORE-INTEREST-EXPEN> 73,467
<TOTAL-INTEREST-EXPENSE> 30,159
<NET-INCOME> 43,308
0
<EARNINGS-AVAILABLE-FOR-COMM> 43,308
<COMMON-STOCK-DIVIDENDS> 0
<TOTAL-INTEREST-ON-BONDS> 22,047
<CASH-FLOW-OPERATIONS> 110,175
<EPS-BASIC> 43,308
<EPS-DILUTED> 43,308
</TABLE>