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<br />During an inspection trip, the Chief
<br />Engineer noted the work that Mexico
<br />is undertaking to protect its lands in
<br />the delta area. Mexico was raising the
<br />heights of some levees, building new
<br />levees, and eliminating constrictions in
<br />existing channel areas. The Chief
<br />Engineer also ascertained that the
<br />existing levees and elevated canal
<br />lines running from the river into the
<br />Mexicali Valley would protect
<br />Mexicali Valley and Imperial Valley
<br />lands against flood flows exceeding
<br />70,000 cubic feet per second, which
<br />flows are greatly in excess of the
<br />revised Hoover Dam Flood Control
<br />Regulations design flows, which are in
<br />process of formal adoption.
<br />The problem of flooding in Mexico
<br />was a topic discussed at meetings of
<br />the Commission of the Californias,
<br />which consists of representatives of
<br />the State of California and the
<br />Mexican State of Baja California. The
<br />Chief Engineer answered inquiries
<br />from California representatives relative
<br />to the excess flows.
<br />Meetings were called by the Water
<br />and Power Resources Service in
<br />August in Salt Lake City to brief state
<br />representatives on alternative water
<br />release plans for the 1979-80 water
<br />year. The recommended plan
<br />proposed release of an additional
<br />700,000 acre-fee! above that required
<br />to meet downstream water
<br />requirements, for the purpose of river
<br />regulation, anticipated flood control
<br />operations to minimize potential
<br />downstream flood damages prior to
<br />1985, and to meet firm power
<br />commitments of the Boulder Canyon
<br />Project power contractors. By letter of
<br />August 24, 1979, the Chief Engineer
<br />concurred in the recommended plan,
<br />stating that this concurrence was
<br />based on analyses that show a very
<br />high probability that reservoirs would
<br />fill prior to commencement of Central
<br />Arizona Project water deliveries. '
<br />By letter of September 7, 1979, the
<br />Service notified Governor Brown that
<br />it had adopted the recommended
<br />plan.
<br />Preliminary estimates of the
<br />1979-80 water year runoff of the
<br />
<br />Colorado River, based upon Upper
<br />Basin snowpack conditions existing in
<br />early 1980, point to another year of
<br />above-average runoff. The Board's
<br />staff, the Department of Water
<br />Resources, and the Metropolitan
<br />Water District had discussions on
<br />possible ways that California water
<br />agencies could make use of any
<br />excess Colorado River flows.
<br />
<br />Program for Banking Water in Lake
<br />Mead
<br />
<br />The study of banking, or storing,
<br />water in Lake Mead, initiated in 1978,
<br />was continued. The concept involves
<br />The Metropolitan Water District of
<br />Southern California increasing its
<br />deliveries from the State Water
<br />Project, taking less than its annual
<br />Colorado River apportionment, and
<br />having a like amount credited to its
<br />account in Lake Mead. In years of
<br />low water supply from the State
<br />Water Project, in addition to its
<br />annual apportionment, Metropolitan
<br />would divert water credited to its
<br />account in Lake Mead.
<br />The Chief Engineer met with
<br />officials of Metropolitan, California
<br />State Department of Water Resources,
<br />and representatives of Arizona and
<br />Nevada, and outlined a general
<br />proposal, criteria for operational
<br />studies, and a scope of study. The
<br />proposal, criteria, and scope were
<br />also reviewed with the Water and
<br />Power Resources Service. It was
<br />agreed that the Board would be lead
<br />agency for the study and that the
<br />Service would perfect a simplied
<br />annual simulation computer model of
<br />the Colorado River system that would
<br />be used in conducting the operational
<br />studies.
<br />As a part of this program, the
<br />Department of Water Resources
<br />prepared a memorandum report
<br />which analyzed the ability of the
<br />California Aqueduct to deliver water
<br />that could be available for the
<br />banking concept under hydrologic
<br />sequences equal to those occurring
<br />from 1906 to 1978 with assumed
<br />future water demand, facility
<br />development, and system operation.
<br />After a review of the results of this
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<br />report, the Department agreed to
<br />conduct additional studies to
<br />determine the availability of State
<br />Project water under different
<br />assumptions of system operations and
<br />completion of the proposed Peripheral
<br />Canal Unit of the State Water Project.
<br />The Service completed initial
<br />development of the computer
<br />simulation model at year's end and
<br />the Board's staff worked with the
<br />staffs of the Metropolitan Water
<br />District and the Service on adapting
<br />the model to the District's computer.
<br />
<br />Water Quality
<br />
<br />Colorado River Salinity Standards
<br />
<br />At the end of 1978, the seven-state
<br />Colorado River Basin Salinity Control
<br />Forum adopted the 1978 revision to
<br />the Colorado River salinity standards
<br />and recommended adoption by the
<br />individual states. The 1978 revision
<br />continued the 1972 flow-weighted
<br />average annual salinities of 723 mg/I
<br />below Hoover Dam, 747 mg!l below
<br />Parker Dam, and 879 mg/I at Imperial
<br />Dam as the numeric criteria for
<br />salinity for the Colorado River. It also
<br />continued the plan of implementation
<br />set forth in the original salinity
<br />standards that encompasses the
<br />federal salinity control program and
<br />state and local actions to control
<br />salinity, and added a requirement that
<br />the Forum's permanent Work Group
<br />conduct an analysis of the results of
<br />the salinity control program,
<br />The States of Nevada and Arizona
<br />adopted the revised standards in
<br />April, New Mexico in May, Utah in
<br />June, and California in September. The
<br />Environmental Protection Agency has
<br />approved the state-adopted revisions
<br />for the five states, The States of
<br />Colorado and Wyoming expect
<br />adoption in early 1980.
<br />California's adoR.tion was delayed
<br />since the California Environmental
<br />Quality Act (CEQA) directs that an
<br />Environmental Impact Report (EIR) be
<br />prepared for any project which could
<br />have a significant adverse
<br />environmental impact. A "project" is
<br />defined to include the approval
<br />activities of public agencies. CEQA
<br />allows for preparation of a Functional
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