WSP01318

• File Number: 8220.101.08
• Description: Glen Canyon Dam/Lake Powell
• State: AZ
• Basin: Colorado Mainstem
• Date: 5/1/1994
• Author: Western Area Power A
• Title: Glen Canyon Dam Interim Operations - Estimated Net Expense - December 1993 through March 1994
• Water Supply Pro - Doc Type: Report/Study

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16,500 cfs (640 MW). The daily maximum fluctuation restriction
of 8,000 cfs (273 MW) was followed for the entire month.

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The first week of January, the Bureau scaled down its snowpack
projections, reducing Glen Canyon releases for WY 1994 to
8,230,000 AF, resulting in cut backs in the generation from Glen
Canyon and the Aspinall units to save water for summer
operations.

The January 17th Los Angeles earthquake tested the efficacy of
the Salt Lake City Area and the Southwestern interconnected
systems. Large transmission segments and load centers in the Los
Angeles region were displaced, effectively severing several
interconnect ties to utilities in the Southwest and the
Northwest. The Los Angeles Department of Water and Power
(LADWP), had surplus energy availability because of its inability
to reach its load areas. Western purchased 100 MWjhour of this
discounted energy from LADWP for SI8.50jMWh. For the week of
January 14, before the earthquake, onpeak non-firm energy was
purchased by Western at S27.00jMWh, resulting in an S8.50jMWh
reduction in energy prices after the Los Angeles earthquake. By
the end of the month, onpeak nonfirm energy prices rebounded to
$24.00jMWh (Secretary's Report, January 28, 1994). Western
reduced releases from Glen Canyon to achieve a target of
800,000 AF for the month, a reduction of 50,000 AF from projected
releases, allowing Western to save water for the summer months.

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3. Power SchedulinQ and Purchases for February 1994

February water releases from Glen Canyon totaled 689,000 AF. The
weekday generation pattern was pre-scheduled at approximately
10,000 cfs (390 MW) during offpeak hours ramping up to a maximum
of 16,000 cfs (618 MW) during onpeak hours for a majority of the
month, staying within the daily maximum fluctuation restriction
of 6,000 cfs (232 MW) per day. Weekend releases were adjusted
downward to follow reduced weekend loads.

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In early February the availability of economy energy was tight
due to cold weather and unit outages in the Four Corners Area of
Utah, Arizona, Colorado, and New Mexico. For several days, 'Rocky
Mountain Generation Cooperative (RMGC) could only provide 50 MWh
of the 90 MWh, that was agreed upon for February. Surplus Navajo
generation from Lower Colorado was used to replace a portion of
the RMGC energy (Secretary's Report, February 11, 1994). Prices
for onpeak non-firm energy escalated to $30jMWh for the week of
February 7, in contrast to the average onpeak purchase price of
$26.75jMWh for the entire month of February.

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On February 21 and 22, the Bureau conducted a unit acceptance
test for Morrow Point, resulting in decreased generation from
Morrow Point and Blue Mesa. The Glen Canyon monthly release
target was not met by approximately 9,000 AF, due to the test.
Purchase power requirements, during this test, were met by long-
term agreements with RMGC and Navajo (Secretary's Report.,
February 25, 1994).

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