[Federal Register Volume 62, Number 41 (Monday, March 3, 1997)]
[Notices]
[Pages 9447-9448]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 97-5144]


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DEPARTMENT OF THE INTERIOR
Bureau of Reclamation


Operating Criteria and 1997 Annual Plan of Operations for Glen 
Canyon Dam

AGENCY: Bureau of Reclamation, Interior.

ACTION: Adoption of operating criteria and 1997 annual plan of 
operations.

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SUMMARY: Pursuant to the Grand Canyon Protection Act of 1992, the 
Bureau of Reclamation (Reclamation) is required to prepare formal 
Operating Criteria and an Annual Plan of Operations following 
completion of an audit by the General Accounting Office (GAO) and the 
Record of Decision (ROD) on the Operation of Glen Canyon Dam. The GAO 
audit was completed on October 2. 1996, and the Glen Canyon Dam 
Operation ROD was signed on October 9, 1996. Draft copies of the 
proposed Operating Criteria and the 1997 Annual Plan of Operations were 
distributed to Governors of the Colorado River Basin States, the Upper 
Colorado River Commission, appropriate Federal agencies, Indian Tribes, 
representatives of academic and scientific communities, environmental 
organizations, the recreation industry, contractors for the purchase of 
federal power produced at Glen Canyon Dam, and others interested in 
Colorado River operations.

FOR FURTHER INFORMATION CONTACT: Mr. Bruce Moore, Bureau of 
Reclamation, 125 South State Street, Room 6107, Salt Lake City, Utah 
84138-1102; telephone: 801-524-3702.

SUPPLEMENTARY INFORMATION: The Operating Criteria specify the 
requirements for an annual report of operations under the Grand Canyon 
Protection Act, a periodic review of Operating Criteria, and details 
regarding operational constraints. These constraints include maximum, 
minimum, and daily fluctuation flow rates, maximum ramp rates, 
emergency exception criteria, flood frequency reduction measures, habit 
maintenance flows, and beach/habitat building flows.
    The 1997 Annual Plan of Operations reflects the operation of Glen 
Canyon Dam consistent with the Operating Criteria. Monthly releases are 
expected to vary between 600,000 acre-feet and 1,500,000 acre-feet and 
daily fluctuations will likely vary between 6,000 cfs/day and 8,000 
cfs/day depending on monthly release volumes. The revised maximum daily 
flow rate of 25,000 cfs and the maximum upramp rate of 4,000 cfs/hr. 
will be placed into effect following signing of these documents by the 
Secretary of the Interior. The following paragraphs contain the final 
text of the Operating Criteria and the 1997 Plan of Operations for Glen 
Canyon Dam.
    Operating Criteria: These Operating Criteria are promulgated 
according to section 1804 of Public Law 102-575, the Grand Canyon 
Protection Act of 1992. They are to control the operation of Glen 
Canyon Dam, constructed under the authority of the Colorado River 
Storage Project Act. These Operating Criteria are separate and apart 
from the Criteria for Coordinated Long-Range Operation of Colorado 
River Reservoirs prepared according to the Colorado River Basin Project 
Act of 1968.
    1. Annual Report: As required in the Grand Canyon Protection Act, a 
report shall be prepared and submitted to Congress annually. This 
report will describe the operation of Glen Canyon Dam for the preceding 
water year and the expected operation for the upcoming water year. The 
annual plan of operations shall include such detailed rules and 
quantities as are required by the Operating Criteria contained herein. 
It shall provide a detailed explanation of the expected hydrologic 
conditions for

[[Page 9448]]

the Colorado River immediately below Glen Canyon Dam.
    2. Review of Criteria: The Secretary of the Interior shall review 
these Operating Criteria as the result of actual operating experiences 
to determine if the Operating Criteria should be modified to better 
accomplish the purposes of the Grand Canyon Protection Act. Such a 
review shall be made at least every 5 years in consultation with the 
appropriate Federal agencies, Governors of the Colorado River Basin 
States, Indian Tribes, representatives of academic and scientific 
communities, environmental organizations, the recreation industry and 
contractors for the purchase of Federal power produced at Glen Canyon 
Dam.
    3. Specific Operational Constraints: The plan of operations will 
follow the description of the preferred alternative (Modified Low 
Fluctuating Flow) in the Operation of Glen Canyon Dam Final 
Environmental Impact Statement and its Record of Decision. The specific 
criteria are as follows:
    Minimum Releases--8,000 cfs between 7 a.m. and 7 p.m. and 5,000 cfs 
at night.
    Maximum Releases--25,000 cfs. Several circumstances warrant 
exception to this restriction. These are the Beach/Habitat Building 
Flows and the Habitat Maintenance Flows (both described below) and the 
release of large volumes of water to avoid spills or floodflow releases 
from Glen Canyon Dam. These latter releases would most likely result 
from high snowmelt runoff into Lake Powell; if such high releases above 
25,000 cfs are required, they shall be made at constant daily flow 
rates.
    Allowable Daily Flow Fluctuations--5,000 cfs/24 hours for monthly 
release volumes less than 600,000 acre feet; 6,000 cfs/24 hours for 
monthly release volumes of 600,000 to 800,000 acre feet; and 8,000 cfs/
24 hours for monthly release volumes over 800,000 acre feet.
    Maximum Ramp Rates--4,000 cfs/hour when increasing, and 1,500 cfs/
hour when decreasing.
    Emergency Exception Criteria--Normal powerplant operations will be 
altered temporarily to respond to emergencies. These changes in 
operations typically would be of short duration (usually less than 4 
hours) and would be the result of emergencies at the dam or within the 
interconnected electrical system. Examples of system emergencies 
include:
    <bullet> Insufficient generating capacity.
    <bullet> Transmission system; overload, voltage control, and 
frequency.
    <bullet> System restoration.
    <bullet> Humanitarian situations (Search and rescue).
    Flood Frequency Reduction Measures--The frequency of unanticipated 
flood flows in excess of 45,000 cfs will be reduced to no more than 1 
year in 100 years as a long-term average. This will be accomplished 
initially through the Annual Operating Plan process and eventually by 
raising the height of the spillway gates at Glen Canyon Dam 4.5 feet.
    Habitat Maintenance Flows--Habitat maintenance flows are high, 
steady releases within powerplant capacity (33.200 cfs) not to exceed 
14 days in March, although other months will be considered under the 
Adaptive Management Program. Actual powerplant release capacity may be 
less 33,200 cfs under low reservoir conditions. These flows will not be 
scheduled when projected storage in Lake Powell on January 1 is greater 
than 19,000,000 acre feet, and typically would occur when annual 
releases are at or near the minimum objective release of 8,230,000 
acre-feet. Habitat maintenance flows differ from beach/habitat-building 
flows because they will be within powerplant capacity, and will occur 
nearly every year when the reservoir is low.
    Beach/Habitat-Building Flows--These controlled floods will occur as 
described in the EIS (steady flow not to exceed 45,000 cfs, duration 
not to exceed 14 days, up-ramp rates not to exceed 4,000 cfs/hours, and 
down-ramp rates not to exceed 1,500 cfs/hour) except instead of 
conducting them in years in which Lake Powell storage is low on January 
1, they will be accomplished by utilizing reservoir releases in excess 
of powerplant capacity required for dam safety purposes. Such releases 
are consistent with the 1956 Colorado River Storage Project Act, the 
1968 Colorado River Basin Project Act, and the 1992 Grand Canyon 
Protection Act.
    1997 Annual Plan of Operations: Under the most probable inflow 
conditions in water year 1997, Glen Canyon Dam is expected to release 
about 14.1 million acre-feet through the Grand Canyon to Lake Mead. 
This is about 5.9 million acre-feet greater than the minimum objective 
release and is the result of high snowpack conditions throughout the 
Colorado River basin. Lake Powell is expected to fill in July.
    Monthly release volumes from Glen Canyon Dam during 1997 are 
expected to range from 600,000 acre-feet to 1,500,000 acre-feet. 
Projected daily allowable fluctuations therefore will be 6,000 cfs or 
8,000 cfs (see criteria). With the projected monthly release volumes, 
it is likely that peak daily releases will exceed 20,000 cfs during the 
months of February through July, when monthly release volumes are at 
their highest for the year. Minimum releases of 5,000 cfs at night and 
8,000 cfs during the day and ramping rates of 4,000 cfs/hr increasing 
and 1,500 cfs/hr decreasing will be followed. All of the above is 
outlined in the Record of Decision implementing the preferred 
alternative of the Glen Canyon Dam Environmental Impact Statement.
    With current projected monthly release volumes, daily releases will 
exceed 20,000 cfs during the months of February through July, when 
monthly release volumes are at their highest for the year. Releases 
above 25,000 cfs will be made as steady flows. Since there are concerns 
for possible modifications of the environmental restoration in the 
Grand Canyon accomplished last year with the beach/habitat building 
flow, monitoring of the impacts of this spring's releases will be an 
important objective of the Grand Canyon Monitoring and Research Center 
and may result in fluctuating flows to aid in this effort.
    Every measure will be taken to prevent a powerplant bypass this 
spring in order to preserve the environmental enhancement accomplished 
by the beach/habitat building flow test in April 1996. Water year 1997 
had a January 1, 1997, Lake Powell storage content greater than 19 
million acre-feet; therefore a beach/habitat maintenance flow of 
powerplant capacity is not planned.
    This plan in prepared in conformance with Section 1804(c)(1)(A) of 
the GCPA. Any changes to the plan would require reconsultation in 
accordance with this Act.
    The draft Operating Criteria and the 1997 Annual Plan of Operations 
were discussed at a consultation meeting held on November 21, 1996, 
with the Transition Work Group, which includes many of the same people 
who received draft copies.

    Dated: February 14, 1997.
Eluid L. Martinez,
Commissioner, Bureau of Reclamation.
[FR Doc. 97-5144 Filed 2-28-97; 8:45 am]
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