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<br />50 percent in any year; a continuous accumulated
<br />shortage not to exceed 75 percent; and an accumulated
<br />annual shortage not to exceed ] 00 percent in any
<br />] O-year period.
<br />Planning for new irrigation development was based on
<br />a recognition of physical limitations and legal constraints
<br />on water availability with a consideration of projected
<br />patterns of developments to stabilize and enhance the
<br />regional economy.
<br />
<br />Water Quality
<br />
<br />Attainment of water quality of the basin's streams is
<br />aimed at meeting water quality standards as established
<br />by the various States. For this study, flow requirements
<br />were based on the assumption that effective treatment
<br />would be provided for all wastes prior to discharge. The
<br />degree of trea tmen t would be equivalen t to a biochemi-
<br />cal oxygen demand removal of 85, 90, and 95 percent of
<br />the future target years of 1980, 2000, and 2020,
<br />respectively. Plan formulation studies, therefore, con-
<br />sidered the residua] flow requirements after treatment.
<br />Moreover,. other alternatives to streamflow regulation
<br />were considered. Diversions and holding ponds illustrate
<br />the more probable alternatives, especially for areas
<br />where there is not a sufficient water supply to regulate
<br />streamflows for water quality control. Therefore,
<br />choices were made as to the probable means for
<br />maintaining stream water quality standards on the basis
<br />of costs, uses of water, lega] constraints, and acceptable
<br />shortages.
<br />The analysis of alternatives recognized that, as a
<br />general rule, consideration would be given to such
<br />physical constraints as water yield capabilities and
<br />natural channel losses of flow, and to such institutional
<br />or unique arrangements that preclude flow regulation as
<br />a means for meeting water quality objectives. Also, for
<br />Class I and Il streams, the classes reflecting fishery
<br />values, all quality requirements would be met except
<br />when limited by the constraints cited. For Class III and
<br />IV streams, quality by flow regulation would not be met
<br />except when the stream reach contains a number of
<br />water users and the distance is such that wastes from the
<br />upstream point would not be assimilated, or where there
<br />are significant quantified beneficia] uses of the stream-
<br />flow throughout the reach.
<br />For reservoir operations, acceptable or tolerable
<br />shortages of streamflow for quality purposes were based
<br />on an index defined as the sum of the squares of annual
<br />shortages expressed as a ratio to the annual demand,
<br />converted to a 100-year base. A shortage index of 0.25
<br />was adopted for plan formulation purposes. This index
<br />represents one annual shortage of 50 percent in a
<br />100-year period, 25 annual shortages of 10 percent, or
<br />any combination of annual shortages for which the sum
<br />of the squares of the shortages totaled 0.25 in 100 years,
<br />
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<br />
<br />or 0.10 in a 40-year base period used in the water supply
<br />analyses.
<br />Plan formulation studies considered that water qua]-
<br />ity to meet adopted standards would be met within the
<br />criteria considerations outlined. Insofar as quantifying
<br />outputs, other than meeting standards, these could be
<br />expressed in terms of population served and stream miles
<br />enhanced or preserved.
<br />
<br />Recreation, Fish and Wildlife,
<br />and Natural Environment
<br />
<br />Projections of future demands for outdoor recreation
<br />activities and for fishing and hunting were based on
<br />demonstrated partidpation rates of the population in
<br />the use of water and land resources. In addition; needs
<br />were also outlined for the propagation of fish and
<br />wildlife resources and as opportunities for preserving
<br />areas for fish, wildlife, aesthetic, cultural, and scientific
<br />purposes.
<br />For those features of these functions which are
<br />developmental-oriented, the projected requirements
<br />would be met through incorporation into multiple-
<br />purpose projects and such single-purpose projects, either
<br />water or land oriented, as required. As with all other
<br />functions, physical and legal constraints were applied as
<br />appropriate. Where certain features, especially those that
<br />are oriented toward a natural environment, are competi-
<br />tive with other uses of land and water, alternatives were
<br />developed to define the degree of competition and the
<br />outputs gained or foregone in comparing the alternative
<br />choices.
<br />All other items riot directly involved with water
<br />resource development, or those requiring legal and
<br />institutional changes or re-arrangements, were outiined
<br />in terms of composition, costs, and future actions
<br />required for implementation. For the most part, these
<br />items, such as trails, historic landmarks, and general
<br />beautification practices, do not and are not affected by a
<br />water and related land resource development plan.
<br />
<br />COST ESTIMATING CRITERIA
<br />
<br />The criteria for estimating the costs of the various
<br />elements of the framework plan included those items
<br />reflecting group or public action, and items that are a
<br />responsibility of the private sector, but reflect significant
<br />financial assistance available through Federal grants and
<br />loans. The costs presented for the framework plan
<br />reflect the first cost of development and no attempt was
<br />made to determine investment costs requiring estimates
<br />of construction periods and interest rates.
<br />Plan components for which cost estimates were
<br />prepared include: Dams and reservoirs and other on-site
<br />features; levees, Iloodwalls, channel improvements, and
<br />
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