WSP05057

• File Number: 8270.100
• Description: Colorado River Basin Water Quality/Salinity -- Misc Water Quality
• Basin: Colorado Mainstem
• Water Division: 5
• Date: 1/1/1983
• Title: Colorado River Water Quality Improvement Program - Status Report
• Water Supply Pro - Doc Type: Report/Study

range of salinity increases which represents basin development to the year
2000, the average loss value has been established at $343,000 per mg/L per
year at Imperial Dam. This average value is based on 1976 economic condi-
tions in the Lower Basin and must be indexed up to current economic condi-
tions. The present (1982) value of projected total economic losses in the
Lower Basin due to projected salinity increases between 875 and 1,225 mg/L
at Imperial Dam is now about $513,300 per mg/L per year. Under the CRWQIP,
an approach is being established to prioritize construction so that the
most cost-effective measures will be implemented to meet program goals;
Reclamation is attempting to determine which of the units of the CRWQIP
have the greatest potential for salt concentration reduction for the least
amount of money expended. For eval uat i on purposes, the incremental cost-
effectiveness of a potential salinity control measure is compared against
the cost-effectiveness of other poss i b 1 e control measures to determi ne
whether the specific measure should be implemented.

Figure 12 shows a breakout of the total average economic loss value of
$343,000 per mg/L per ye ar indexed up to $513,300 in 1982 do 11 ars . The
municipal and industrial sector carries most of the economic burden of
salinity increases in the Lower Basin. Moreover, regional indirect agri-
cultural losses to the economy are significantly larger than direct agri-
cultural losses accrued to the farmer in the Lower Basin.

Present cost allocation provisions under Public Law 93-320, the Colorado
River Basin Salinity Control Act, state that the Federal Government will be
responsible for 75 percent of salinity control costs under Title II provi-
sions for the units authorized for construction. The remaining 25 percent
contribution will be derived from Upper and Lower Basin development fund
revenues. Other specific cost-sharing provisions for salinity control
projects are being developed. In a contract signed with water users in the
Grand Valley Unit area, operation and maintenance costs of governmental
funded lining to be installed in canal and laterals will be the responsi-
bility of the local beneficiaries and water users association. There are
other opportunities for cost-sharing programs in salinity control related
to water and energy resource development in the Basin.

Environmental Aspects

The CRWQIP is designed to serve the water quality improvement component of
the environmental quality objective which can be measured directly by eco-
nomi c effects on Basin water users. Although not all effects have been
determined or quantified, water quality improvement programs do extract a
"cost" of other natural resources in terms of land, water, solid wastes,
and energy consumption.

Investigations thus far have identified more than 8,500 acres of land that
may be directly affected by structural project features and brine evapora-
tion ponds. In the process of removing salt by structural barriers,
collection systems, desalting, or disposal ponds, over 120,000 acre-feet of
water per year may also be removed from the river system. Over 1 million
tons of salts per year may remain behind in long-term pond storage.
Extensive design efforts are underway to assure that salts and solid waste

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