Avista Requesting to Lower Natural Gas Prices for Washington and Idaho Customers...

Avista Requesting to Lower Natural Gas Prices for Washington and Idaho
Customers for Second Time This Year

Price decreases would make customer rates the lowest in four years

SPOKANE, Wash., May 19 /PRNewswire-FirstCall/ -- Avista today filed requests
with the utility commissions in Washington and Idaho to reduce natural gas
prices by 8.1 percent and 6.7 percent respectively, effective June 1. If
approved, this would be the second time in 2009 that Avista customers in both
states will see a decrease in their natural gas rates.

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"Natural gas prices have continued to decline since our last rate decrease was
effective in January. We know many of our customers are concerned about
expenses in this economy and we want to pass these additional savings on to
them as soon as possible," said Kelly Norwood, Avista vice president for state
and federal regulation. "In addition, we are now purchasing natural gas for
the next heating season and plan to file by September for a third decrease,
provided natural gas prices do not escalate substantially over the summer."

If the request is approved by the Washington Utilities and Transportation
Commission (WUTC), a residential customer using an average of 70 therms per
month would see a decrease of $7.02, or 8.1 percent, for a revised monthly
bill of $79.43. Avista's 146,000 Washington natural gas customers received a
3.0 percent decrease in January 2009.

If the request is approved by the Idaho Public Utilities Commission (IPUC), an
Idaho customer using an average of 65 therms per month would see a $5.26, or
6.7 percent decrease for a revised monthly bill of $72.97. Avista's 73,000
Idaho natural gas customers received a 4.7 percent decrease in January 2009.

Purchased Gas Cost Adjustment (PGA) filings are usually made annually in the
fall to pass through changes in the cost of natural gas Avista acquires to
serve customers. Each month Avista calculates the difference between the price
that Avista pays for natural gas and the price that customers pay in rates.
The difference between the two amounts is set aside and trued up through
annual PGA adjustments. In this instance, natural gas prices have declined, so
Avista is refunding the difference to customers prior to its annual PGA
filing. These changes in natural gas costs and the PGA rate adjustments do not
increase or decrease Avista's earnings.

About 75 percent of an average residential customer's monthly Avista natural
gas bill is the cost of the gas and pipeline transportation. The remaining 25
percent is Avista's fixed costs to provide natural gas service through its
distribution system.

Avista offers a number of rebates and incentive programs to help residential,
commercial and industrial customers manage their costs through reduced energy
use. Some residential efficiency improvements may also qualify for Federal
energy tax credits. Information on Avista's energy efficiency programs and
low- and no-cost energy saving ideas is available at www.everylittlebit.com.

Avista Corp. is an energy company involved in the production, transmission and
distribution of energy as well as other energy-related businesses. Avista
Utilities is our operating division that provides service to 355,000 electric
and 315,000 natural gas customers in three Western states. Avista's primary,
non-regulated subsidiary is Advantage IQ. Avista stock is traded under the
ticker symbol "AVA." For more information about Avista, please visit
www.avistacorp.com.

Avista Corp. and the Avista Corp. logo are trademarks of Avista Corporation.

This news release contains forward-looking statements regarding the company's
current expectations. Forward-looking statements are all statements other than
historical facts. Such statements speak only as of the date of the news
release and are subject to a variety of risks and uncertainties, many of which
are beyond the company's control, which could cause actual results to differ
materially from the expectations. These risks and uncertainties include, in
addition to those discussed herein, all of the factors discussed in the
company's Annual Report on Form 10-K for the year ended Dec. 31, 2008, and the
Quarterly Report on Form 10-Q for the quarter ended March 31, 2009.

SOURCE Avista Corp.

Debbie Simock of Avista Corp., +1-509-495-8031, debbie.simock@avistacorp.com,
or Avista 24/7 Media Line, +1-509-495-4174