[This document summarizes the 1988 status of the Salton Sea, its problems and their potential solutions. Gulf waterway enthusiasts will note with interest that the 1988 cost estimate for this option was only $250,000,000! You missed your big chance! An especially valuable sectioon of the document is Appendix F, a 59-page "summary of the institutional and legal structure and requirements which will apply to the primary Salton Sea management options being considered." Many government agencies have powers and responsibilities with respect to the Sea and this appendix is the best available introduction as to who is responsible for what. Its relevance has been little altered by the recent formation of new entities such as the Salton Sea Authority. S. Hurlbert, SDSU, December 1998]
Developed for:
The California Resources
Agency
Developed by:
Meyer Resources, Inc.
Davis, CA
July, 1988
Table of
Contents Page i 1 3 i ) Flooding 3 ii) Salinity 4 iii) Pollution 4 6 a) General Economic Activity--and the Role of
Agriculture 6 b) Land Values at the Sea 7 c) Recreation at Salton Sea 9 d) Potential Economic Impact With and Without Control of
Salinity and Associated Problems at Salton Sea 11 4. Goals
and Objectives of Present Agencies/Interests at Salton
Sea 13 19 6. Likely
Physical Trends Affecting the Future of Salton Sea 21 i) Decreased Drainage Inflow to Salton Sea 21 ii) Increasing Salinity at Salton Sea 22 iii) Pollution 22 iv) Recreation/Retirement Complexes in the Northwest
quadrant of the Sea 22 v) Increasing Importance of Solar Energy 23 23 A. Options to Stabilize Salinity and Sea Level 23 1. Pumpout/Kesalination/Solar Generation 23 2. A Saltwater Impoundment in Salton Sea 24 3. Gulf Waterway Option 25 B. Supplementary Options 26 1. Colorado River Surges 26 2. Pump-back of Brine Water to Yuma 26 C. Dealing with Pollution at Salton Sea 27 1. Cleanup of the New River 27 2. Cleanup of the Alamo River 28 3. Management of Selenium at Salton Sea 28 29 31 a) Coordination of Remedial Efforts at Salton Sea 32 b) Availability of Knowledge, the Issue of Timing and
Salinity Targets at Salton Sea 33 c) Present Status and Future Requirements for Remedial
Options at Salton Sea 36 d) A General Strategy for Remedial Action at Salton
Sea 38 e) Contributions to Remedial Action at Salton Sea 40 f) Feasibility of Action Beyond 1991-94 43 i) Equity in Supporting Remedial Action at Salton Sea 44 ii) Potential Fiscal Resources Available to Remedial Work
at Salton Sea 48 h) Options for Improvement at Salton Sea--A
Conclusion 53 10. Organizational
Options Associated with Remedy at Salton Sea 56 a) Timing for Resolution of Organizational Issues 56 b) Focus of Organization Discussion 56 i) Organizational Leadership in the Interim 1988-90
Period 57 ii) Efficiency in Maintaining Remedial Momentum at Salton
Sea 57 iii) Need for a Coordinated Funding Plan 58 vi) Information/Access for Other idnterested Parties 58 v) A Summary of Organization Options for the 1988-90
Period 59 Appendix
A Historic Salton Sea Water Budget 63 Appendix
B Components of Inflow to Salton Sea 64 Appendix
C Historical Change to Salton Sea Salinity and
Elevation 65 Comments on Salton Sea by the U.S. Envirnomental
Protection Agency 66 References 70 Summary Analysis of Authorities and Responsibilities
Associated with the Salton Sea [separate file] A Review of the Potential Biological Responses to
Salinity Changes in the Salton Sea [separate
file]
This report identifies present progress and future opportunities to manage salinity levels and potential flooding at Salton Sea. It also discusses ongoing activity to control pollution at the Sea and in the New and Alamo River drainages.
There is near unanimous agreement between involved agencies and interests that major beneficial uses associated with the Sea mainly, disposition of agricultural drainwater, sport fishing, nature enjoyment, general recreation and residential/retirement activity should be preserved and, if possible, enhanced. Conversely, failure to control the increasing salinity gradient in the Sea (now at about 41,000 ppm), as well as to effectively manage flooding and pollution, will force action by a number of federal, state and local agencies (Table I). The choice is not, therefore, between action and no action-but between action and reaction.
Three general alternatives capable of improved salinity control and flood management have been identified. These alternatives are: construction of an in-Sea impoundment to concentrate salts through evaporation, leaving salinity in the balance of the Sea at lower levels; pumping water out of the Sea, evaporating the water, and using residual salts to generate Solar energy; and constructing a waterway capable of accommodating pleasure craft from the Salton Sea to the Gulf of California, to effect water exchange. The estimated costs of these alternatives range from $100 million to $350 million. Anticipated benefits from control of salinity, flooding and pollution are expected to be much greater, however.
Each alternative has its own interested supporters. Further, necessary scientific data to estimate required salinity targets at the Sea will not be available until mid-1990. This suggests an incremental approach to problem solving at the Sea: developing needed scientific data over the next two year period; developing the three identified alternatives further and establishing a detailed funding strategy for each during the same period; and making a decision on which alternative(s) should be fully implemented subsequent to establishment of salinity targets in 1990. This progression is outlined in Figure 1 (pg. 39). Such an incremental strategy will be essential to effective remedy of the Sea's problems. The remedies proposed are large scale and complex and will only be achieved by continued effort over several years. Such remedies have significant financial requirements, dictating development of a similarly measured and sophisticated funding approach, if implementation is to be successful. Lack of such a coordinated funding approach has likely been a major impediment to resolution of problems at the Sea over the past two decades.
Considerable progress has already been made along these lines during present analysis. The key to this progress has been the association of interested participants with each of the remedial alternatives identified. These groups are referred to as "action teams" in our report, and can play a leading role in progressive management of the problems identified. They are identified in Table II. Financial resources to pursue recommended interim tasks: to set salinity standards; to update the In-Sea Impoundment option; and to conduct a reconnaissance evaluation of the Gulf Waterway option are in hand, or are likely to be obtained shortly. The Pumpout/Evaporation/Solar option is ready for modular testing and development. Its immediate funding needs are consequently more substantial. Some funding and in kind support has already been committed to this option, and interested parties are working with the Facilitator to develop further funding. The present status of recommended programs is described in Table III.
In sum, we have concluded that remedy at Salton Sea is desired by virtually all parties, would be beneficial and is possible. We have identified a progressive strategy to that end. Actual movement by interested agencies toward the potential remedies indicated in our report can already be observed.
|
A Summary of Principal Agency Authorities and Responsibilities, Should Adverse Trends at Salton Sea Continue |
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Agencies |
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1. |
Salinity continues to increase |
l a. |
Exceeds specified standard(s) |
- RWQCB |
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|
l b. |
Adversely affects fish and wildlife |
-CF&G |
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2. |
Pollution at unsatisfactory levels |
2 a. |
Exceeds health standards |
-CA. Dept. of Health Services |
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|
2 b. |
Adversely affects fish or wildlife |
-CF&G |
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3. |
Water levels at the Sea increase |
3 a. |
Flooding |
-SWRCB |
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The scope of USBR involvement cannot be definitively stated at this stage. |
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Potential Participants--Remedial Action over the 1988-1990 Period |
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1. |
Salinity Standards & Water Quality |
l a. |
Complete salinity studies for sport fish. |
CF&G |
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2. |
In-Sea Impoundment |
2 a. |
Update cost analysis. |
CVWD |
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2 b. |
Consider seismic risk issue |
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3. |
Pumpout/Evaporation/Solar |
3 a. |
Test module. |
IID |
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4. |
Gulf Waterway |
4 a. |
Conduct reconnaissance analysis. |
Corps |
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Preliminary, subject to revision. |
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1. Salinity Standards & Water Quality l a. CF&G l a. Has resources to complete by mid-1990. l b. RWQCB l b. Continued monitoring, testing & development of water
quality standards. l b. Interface with action teams re. requirements &
funding of alternatives. 2. In-Sea Impoundment 2. CVWD 2. Will complete by mid1990 3. Pumpout/Evaporation/ Solar 3 a. IID 3 a. Have committed Imp. Cnty. $100,000. 3 b. USBR 3 b. Has committed to conduct feasibility analysis of Yuma
saline return line. 3 c. CF&G 3 c. Have committed to "in-kind" participation in module
design &testing. 3 d. All team entities (see Table II) 3 d. Have agreed to explore avenues for funding support 3 e. All team entities 3 e. Have agreed to scope module project &assign
sub-tasks. 4. Gulf Waterway 4 a. Corps 4 a. Will likely agree to conduct physical structure
reconnaissance study. 4 b. USBR 4 b. Has agreed to conduct reconnaissance evaluation of
potential environmental impacts. 4 c. CF&G 4 c. Have agreed to participate in above reconnaissance
analysis.
Present Status of Action Teams-Remedial Action at Salton
Sea
SWRCB
EPA
FWS
ORMAT
FWS
FWS
CA. Boating & Waterways
The Salton Sea is a terminal lake, created by accidental flooding from the Colorado River at the turn of the century. Since 1920, the Sea has served as a depository for agricultural irrigation drainage. The Sea also receives storm runoff and scant amounts of rainfall. The drainage water, and in fact, Colorado River water used for irrigation, contains dissolved salts, and this factor, together with evaporation in the area's desert environment has created a saline sea, which, for the past several decades, has approximated ocean salinities [ocean salinity is about 35,000 parts per million (ppm)]. As a result, sport fish were introduced from the ocean, state and federal wildlife refuges were established at the Sea, and activity infrastructure focusing on recreators (primarily boating and fishing) and retirement residences began to expand and prosper.
In recent years, serious concern has been evident over the Sea's future. The trend toward increasing salinity of Sea waters was temporarily abated in the late 1970's and early 1980's, but this was achieved by relatively high levels of water inflow into the Sea from rivers and drains (the Sea's only source of "fresh" water), which caused flooding. Salinity in the Sea now exceeds 40,00 ppm, and while there is not yet substantive measurable evidence of fishery decline, damage to the Sea's fish populations, attendant loss of significant portions of dependent wildlife and increased unpleasant odors from the Sea itself can be predicted with certainty if salinity increases continue. Concern over pollution, both organic and inorganic, has also been evident in recent years.
The Sea continues as a viable depository of agricultural drainage from the Imperial and Coachella Valleys today. However, recreational use of the Sea has declined markedly, largely, it appears, as a result of recent posted warnings against human contact with the Sea in some areas and respecting consumption of fish. The envisioned broader recreation residential potential of the Sea is also clearly not being realized. (See Section 4).
Finally, the conditions and trends outlined here are expected to continue if left to take their own course. Such evolution threatens the approximate 100,000 residents of Imperial County, and those residents of Riverside County living in the Coachella Valley, especially persons who value the Sea for resident/recreational purposes, and/or who gain economic benefit from the recreational infrastructure dependent on it. This may be particularly important in Imperial County, where per capita income is lower than the state average, and unemployment often reaches significant levels. Important recreational opportunity for residents of California's populous south coastal area will also be preempted, and national and state wildlife resources will be lost. The Torres-Martinez Indian Reservation is found along the Sea's northwest shore, and would be negatively impacted by these trends.
While threats posed by conditions at Salton Sea are significant, solutions are neither easy nor inexpensive, and are clearly beyond the capabilities of local entities along.
2. Present Significant Problems
i) Flooding
Flooding may not be the most serious problem at Salton Sea, but it is among the most immediate. In 1949, the Sea's elevation stood at 240 feet below Sea Level. Levels gradually increased in subsequent years--and reached a high of 226.6 feet below sea level in 1983, assisted in that year by extensive storm-related runoff. Basic data of Sea levels and water balances are included in Appendix A.
This approximate 13 1/2 foot increase in level of the Sea has flooded several areas near the Sea, and fairly extensive litigation has ensued. The objective of Imperial County, and others, is to prevent future shoreline development below elevation--220 feet. this is about 7 feet above the flood highs of 1983, and should pose an absolute upper level constraint for future planning affecting the Sea. A "desirable" construct might see establishment of a lower absolute Sea level, perhaps approximating 230 feet below sea level--so that some of the flooded shore lands might be reclaimed. This would have the sea declining at least 3 1/2 feet from 1984 levels, to achieve elevations in effect in about 1875.
Parsons (1985) provides historic data on flows of water into Salton Sea through 1984 (Appendix B). In the 1981-84 period, the Sea received an average of 1.3 million acre feet of "fresh" water annually. Of this total 79, percent comes from irrigation drainage, 16 percent from Mexico via the New and Alamo Rivers, and the balance from "other" sources. Of these sources, inflows from IID and CVWD appear to have been decreasing, while flows from Mexico have been increasing.
In sum, potential flooding at Salton Sea likely serves as a constraint on remedial planning. For a variety of reasons, flows from Mexico have been the least predictable contributors to Salton Sea inflow in the past.
ii) Salinity
While flooding provides a constraint to remedial management at Salton Sea, the focal issue at the Sea for more than a decade has involved salinity, which has increased fairly steadily since 1955 until it now exceeds 40,000 ppm (Appendix C). This may be approaching the upper range of tolerance for sport fish species that inhabit the Sea. Increased salinity is occurring because the Sea is a closed sink and evaporation in the Sea concentrates the salts found in Colorado River water supplies. (Again see Appendix A). In sum, any attempt to stabilize salinity levels in the Sea must consider both volume and salinity of inflow to the Sea; surface area of the Sea and related evaporation; and any removal of saline water from the Sea.
iii) Pollution
Significant localized pollution problems exist at or near Salton Sea. The New River, which flows into the United States from Mexicali, and hence runs northward through farm land to the Salton Sea has been a focal point of concern. At the border, the New River flows at about 350 cfs, an increase from about 50 cfs in 1950. This increased flow has resulted from expanded agricultural activity in Mexico, and from growth of Mexicali, now an urban industrial area of over 1 million people. The waters of the New River are grossly polluted where they cross the international boundary. About half of Mexicali is without a sewer system, and considerable human, livestock and industrial waste finds its way untreated into the River. Specifics are provided in a 1987 report by Montgomery Engineers for California Regional Water Quality Control Board. On the immediate United States side of the boarder, the waters of the New River are posted as dangerous to humans, and also provide an attractive breeding ground for mosquitoes that carry encephalitis.
As the New River flows northward toward Salton Sea it is joined by agricultural drain water, substantially increasing flows at the River mouth, and diluting pollutants from the upper river. Nonetheless, health warnings are present at the river mouth, as are strong adverse odors. The necessity of dealing with a foreign country complicates effective management of this ongoing problem.
Selenium has also been detected in concentrations that sometimes exceed EPA advisory levels, in portions of the Salton Sea. A review of these standards is presently underway. Concentrations do not appear sufficient to result in large scale preemption of agricultural activity in the Imperial Valley, although basic data is still being collected.
Action to address both the New River and selenium pollution problems affecting Salton Sea will be required. That action will most probably focus on treatment of New River flows just north of the international boundary, and on some adjustment in practices associated with management of agricultural drain water. Momentum toward best management practices in agriculture, and to control Colorado River selenium impacts will also 1ikely contribute positively to overall management of the selenium issue.
Management of pollution problems is not interconnected directly to salinity and flooding issues. Our approach here will be to first focus on salinity and flooding issues, and then consider pollution management in a following section.
3. Values at Stake at Salton Sea
a) General Economic Activity -- and the Role of Agriculture
Agriculture is the largest contributor to the economic well-being of Imperial County, producing average annual gross crop revenue of $733 million during the 1984-86 period and over 11,000 jobs (County of Imperial, 1987). Government is the second largest employer in the county, providing about 8,000 jobs annually. An overall profile of wage and salary employment is provided in Table 1.
|
Employment Profile for Imperial County |
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Agriculture |
11,200 |
32 |
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*Numbers do not add to 100 due to rounding. |
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Per capita income in Imperial County is lower, while unemployment is higher than for the state as a whole (Table 2).
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Per Capita Income and Rate of Unemployment- Imperial County and the State of California |
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Per Capita Income (1984) |
$9,980 |
$14,374 |
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Only an eastern portion of Riverside County abutts the Sea, in the Coachella Valley area. According to the Coachella Valley Water District (CVWD), crops serviced by CVWD are also of major significance, generating some $286 million in farm revenue in 1985. Riverside County varies considerably, from its urbanized western extremities to more rural eastern districts. Consequently, the overall county per capita income figure of $13,030 (1984) and unemployment rate of 7.8 percent may overstate economic well-being in Coachella Valley. Even then, Riverside County's overall employment rate was only 37th out 59 counties in 1986.
b) Land Values at the Sea
Land values are another important parameter particularly affected by Salton Sea. Development Research Associates (1969) reported lot values between $2,000 and $4,000 around Salton Sea. In 1972, USBR did a land sales analysis at the Sea, finding an average value of $4,300 per improved lot. They further concluded the land values around Salton Sea were heavily dependent upon an attractive Sea environment.
"...99 percent (plus) of the vacant land value is attributable to the Salton Sea". (pg. 24)
Finally, USBR noted that no significant trend toward increased 1 and value around the Sea was then evident. We also We also checked present lot values at the Sea with appraisers in Imperial and Riverside counties. Information obtained from these sources and from earlier cited studies are displayed in Table 3.
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Data on Serviced Residential Lot Prices- -Salton Sea and Surrounding Areas |
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At present |
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On Salton Sea |
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2,500-4,000 6,000-6,500 1,000-1,500 2,500 3,000-5,000 8,500-10,000 12,000-18,000 10,000-12,000 30,000 50,000 |
Data from Coachella, Indio and Bermuda Dunes are included to illustrate the step-up as one leaves the Sea, moves progressively through Coachella and Indio, and then enters the higher value residential/retirement communities expanding eastward from Palm Springs. Table 3 suggests that lot values adjacent to the Sea have changed little over the past 20 years.
c) Recreation at Salton Sea
Recreation has been an important traditional focus at Salton Sea. Referencing preliminary data for CIC Research (1988) for the California Department of Fish and Game, the following usership may be inferred for the Sea (Table 4).
|
Estimated Southern California Households Visiting Salton Sea |
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in Past 12 Months |
Not in Past 12 Months |
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|
County |
% |
_(1986)_ '000 |
% |
_(1986)_ |
|
Imperial |
2.7 2.9 2.1 4.8 4.0 2.3 2.0 1.5 |
8.3 86.6 16.5 18.4 31.2 5.2 2.5 1.1 |
20.7 10.8 9.6 22.8 14.8 7.0 6.6 7.0 |
63.6 322.5 75.4 87.4 115.4 15.8 8.2 5.1 |
|
Total |
3.9 |
174.7 |
13.1 |
698.9 |
The CIC study reported fishing as the most important motive for visiting the Sea, followed by camping, picnicking and boating. Applying preliminary data from an intercept survey in the same report, it may be inferred that the participation levels identified in Table 4 support a total of 1.6 million recreation days annually at Salton Sea. Using a further CIC (1988) preliminary expenditure estimate of $218.58 per trip, annual recreational expenditures of $103.1 million can be associated with Salton Sea recreation. Finally, respondents to the CIC survey indicated that they considered Salton Sea a major recreational area, that improvements to wildlife and fishing at the Sea were required, and that they would be willing to pay a small fee to achieve these objectives.
In 1969, Development Research Associates (DRA) completed a comprehensive analysis of benefits associated with Salton Sea. This study is of interest for two reasons. First, it provides a relative measure of recreational use, compared to the more recent CIC preliminary estimate. Second, it developed a careful estimate of economic benefits to the Salton Sea area with and without effective management of salinity at the Sea.
User estimates for 1967 by DRA amounted to approximately 1.5 million annual recreation days. This is very close to the estimate of million days inferred from 1987-88 CIC data and suggests that as with land values, recreational use in the Salton Sea area seem little changed over the past two decades.
d) Potential Economic Impact With and Without Control of Salinity and Associated Problems at Salton Sea
Since the early studies by Development Research Associates (DRA) (1969) and USBR (1972), considerable effort and discussion has occurred, but no effective remedial focus has yet been established and implemented with respect to problems of salinity, flooding and pollution at Salton Sea. As a result, recreational participation, land values and general levels of economic activity around the Sea have not changed much over the past two decades, and have not kept pace with trends in adjacent Southwestern California. In this sense, failure to deal effectively with the Sea's problems can be equated with loss of significant potential economic and social benefits.
The DRA study seems particularly useful for measuring benefits foregone, for the recreational participation rates and land values that they considered in 1969 still approximately hold around the Sea today, while risks to fish and wildlife resources have increased. Combining estimates from the DRA study, updated to present dollars, with preliminary results from CIC (1988), we can develop policy level estimates of benefits at stake at Salton Sea. These estimates do not provide a detailed forecast of future economic options. Such a forecast would require far more detailed data and analysis than is provided here. Data is considered sufficient, however, to develop "order of magnitude" estimates of potential gains or losses associated with management of the Sea. Results are presented in Table 5. Procedures are as follows.
i) For the "no solution alternative", assume general recreation remains at present levels, then drops to half after the year 2000, when fish and fifty percent of wildlife are assumed to disappear. This is more optimistic than the scenario used by DRA;ii) Relate preliminary recreational direct expenditure data from CIC to the adjusted trend lines;
iii) Update DRA estimates of residential construction values at Salton Sea, to present dollars;
iv) Update DRA's estimates of increase in recreation-oriented commercial construction activity, to present dollars;
v) Assume construction values for new residences and for recreation-related commercial establishments increase by 2.25% annually if fish and half of wildlife are lost. This may be an optimistic projection.
Year 1987
Potential Economic Values Associated with
Effective
Management at Salton Sea
Expenditures
Housing Construction
Commercial Construction
Solution
Solution
Solution
2000
2010
2020
165.6
347.3
372.1
103.1
51.6
51.6
252.0
573.3
919.8
172.5
215.5
269.2
6.7
21.1
25.6
4.0
56.2.0
Again, these estimates are conjectural and are presented for comparative policy purposes. They are, however, generally reflective of prior economic analysis and ongoing conditions at Salton Sea. They suggest that effective management of salinity, flooding and pollution problems at Salton Sea could generate over $200 million in additional annual recreation expenditures, and at least $670 million in additional construction activity. These estimates could very well be conservative, particularly as they fail to incorporate likely increases in land value associated with the enhancement process.
In conclusion, the importance of the Sea's role for agriculture must be reemphasized. Our discussion of economic stakes at Salton Sea has focused on value foregone by residential and recreational complexes, should the Sea's problems remain unresolved. Agricultural productivity has been, and remains today the most important economic activity dependent on Salton Sea (recall Section 3a). Consequently, actions to capture the substantial benefits illustrated in Table 5 must be consistent with protection of the traditional agricultural benefits that have sustained the region.
4. Goals and Objectives of Present Agencies/Interests at Salton Sea
Based on foregoing discussion of economic stakes and ongoing problems at Salton Sea, the goals and objectives of existing affected entities are fairly predictable. Tables 6 and 7 summarize these objectives, based on a formalized survey taken during our ongoing study period. Not all agencies answered the survey in the same way, and some interests have not yet responded. The results presented here are consequently "as received by this date". Further, EPA provided narrative response. This is enclosed in Appendix D. Table 6 summarizes returns from agencies indicating "direct involvement's in each indicated use only. Table 7 supplies a broader indication of relative support, regardless of whether a direct linkage exists or not.
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Priorities Respecting Future Use of Salton Sea - - For Agencies/Interests Having Direct Involvement |
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Uses |
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County |
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FWS |
Ass. BradIey's |
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Receive Ag. |
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ReceiveTreated |
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Boating |
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Fishing |
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Parks |
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Mining |
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Geothermal |
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Solar Energy |
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Shoreline |
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Storm Runoff |
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Untreated Waste |
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Legend: R = |
Required use |
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Priorities Respecting Future Use of Salton Sea -- All Agencies and Interests |
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Uses |
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County |
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Ass. BradIey's |
Salton Sea |
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Receive Ag. |
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ReceiveTreated |
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Boating |
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Swimming |
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Fishing |
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Parks |
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Mining |
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Geothermal |
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Solar Energy |
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Shoreline |
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Storm Runoff |
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Gulf |
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Untreated |
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Legend: R = |
Required use |
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Legend: See Table 6
Tables 6 and 7 indicate that failure to resolve problems at Salton Sea cannot be related to lack of common objectives. While each agency or interest sees its own particular objectives as unique, there is a broad tolerance of the interests of others. Table 8 considers future action priorities at the Sea, for those agencies/interests who consider themselves directly affected. Table 9 provides the same priority information for all agencies/interests, whether affected or not.
|
Action Priorities at Salton Sea -- Directly Affected Agencies/Interests |
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Action |
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County |
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Control Salinity |
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Lower Sea Level |
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Stabilize Sea Level |
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EstablishMinimum |
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Treat New River |
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Treat Alamo |
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Control Selenium |
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Turn Sea into Waste |
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Raise SeaLevel |
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Legend: R = |
Action is required |
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Action Priorities at Salton Sea -- All Agencies |
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Action |
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County |
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Health Serv. |
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Ass. BradIey's |
Salton Sea |
Salton |
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Control |
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Lower Sea |
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Stabilize |
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Establish |
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Treat New |
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Treat Alamo |
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Control |
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Turn Sea |
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Raise Sea |
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Legend: See Table 8
Again, there is considerable agreement over actions to be taken at Salton Sea. It is our consequent conclusion that impediments to effective action do not lie in the area of consensus on "requirements or "needs".
5. Authorities and Responsibilities - Existing Conditions
Failure to resolve problems at Salton Sea will likely trigger required actions by a number of federal, state and local agencies. The nature of these legal responsibilities, together with associated response to the major remedial alternatives identified in this report, are generally discussed in Appendix F. In Table 10, we identify the major issues, triggering events and agencies where action will likely be required as a result of such events. It should be emphasized that this tabular presentation is in summary form. Readers should consult Appendix E for a more extensive discussion of potential agency authorities and responsibilities. In fact, it will be recognized that, given the time and resources available to our project, Appendix E is itself somewhat summary in nature.
Finally, we do not represent that Table 10 identifies all legally responsible agencies. Rather, we have attempted to identify obvious responsibilities, taking the perspective that these agencies may very well have lead involvement, should the adverse events identified in the table occur.
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A Summary of Principal Agency Authorities and Responsibilities, Should Adverse Trends at Salton Sea Continue |
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Adverse Trends |
Triggering Event |
Agencies |
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1. |
Salinity continues |
l a. |
Exceeds specified |
-RWQCB |
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2. |
Pollution at unsatisfactory |
1 b. |
Adversely affects |
-CF&G |
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2 a. |
Exceeds health standards |
-CA. Dept. of |
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2 b. |
Adversely affects |
-CF&G |
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3. |
Water levels at the Sea increase |
3 a. |
Flooding |
-SWRCB |
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*The scope of USBR involvement cannot be definitively stated at this stage. |
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From Table 10, we conclude that the State Water Resource Control Board (SWRCB) and the Regional Water Quality Control Board (RWQCB) have significant responsibilities in all issue areas, both with respect to maintenance of appropriate quality standards and protection of beneficial uses. The Environmental Protection Agency (EPA), the U.S. Fish and Wildlife Service (FWS) and the California Department of Fish and Game (CF&G) also have significant lead responsibilities. It would appear that local responsibilities are most prevalent with respect to the flooding issue. in the time available, our legal experts were not a b 1 e to reach a firm option concerning the responsibilities of the U.S. Bureau of Reclamation (USBR). While USBR has significant involvement in events at Salton Sea, we have consequently left this as a question.
It is our conclusion, based on Table 10, that "taking no action" is not a choice at Salton Sea. If adverse trends continue, agencies with legal authority and responsibility will eventually be forced to act. The management choice, then, is rather one of action versus reaction with respect to adverse events at Salton Sea.
6. Likely Physical Trends Affecting the Future of Salton Sea
i) Decreased Drainage Inflow to Salton Sea
Consumable water is becoming an increasingly valuable and sought after resource in California. In this context, the State Water Resources Control Board recently directed IID to introduce practices that would conserve greater amounts water in the Imperial Valley. That order is presently being litigated. At the same time, however, IID has developed a water conservation plan and is introducing conservation measures into its water system. IID (1986) estimates that an actual annual savings of 358,000 acre feet might be achieved by such measures- implying a reduction in annual drainage inflow to the Sea of slightly less than this amount. Reductions in inflow of about 15,000 acre feet annually of relatively high quality reclaimed water from wastewater treatment plants are expected during the next decade (Levy, 1986). As the Central Arizona Project goes into full operation, cutbacks in inflows from Mexico via the New River are also expected. Taking these factors together, significant cutbacks of inflow into the Salton Sea are expected over the next decade, perhaps eventually reducing annual inflows to 1 million acre feet of less. This can, in turn, be expected to reduce Sea level.
ii) Increasing Salinity at Salton Sea
It was earlier observed that salinity has increased at Salton Sea since 1955. The conservation measures cited above can be expected to accelerate this trend. Consequently, it is reasonable to assume that without remedial action, marine life in the Salton Sea will eventually die off, and that recreational/retirement activity based on fishing will decline, or at least fall behind other Southern California areas.
iii) Pollution
As Mexicali grows in size, and water flows from Mexico decline, pollution concentrations in the New River will increase. As we have noted, efforts are currently underway to address this issue on both sides of the border. We expect progress to be made but are not optimistic, under existing conditions, that a complete solution is yet in. sight.
iv) Recreation/Retirement Complexes in the Northwest Quadrant of the e-a
High value desert retirement /recreation communities have spread eastward from Palm Springs until they are now only a few miles from the northwesterly boarder of the Sea. This advance to the east and south is expected to continue, and will introduce a new element to the Sea's future over the next decade. The essential question will be whether these developments capitalize on the Sea as a major recreational amenity, or avoid it due to fish and bird die-offs, and any other noxious effects.
v) Increasing Importance of Solar Energy
At present, large scale production of solar energy from salt ponds does not appear commercially feasible in the United States. Energy experts predict, however, that it will become increasingly so over the next 1 to 2 decades. Small piloting facilities have recently come online in the U.S., and Israel is pioneering solar salt pond development at the Dead Sea. Salton Sea has obvious potential in that regard.
7. Remedial Alternatives at Salton Sea
In the course of this and previous analyses, a number of alternative actions that would move toward eventual stabilization of Salton Sea have been identified. These options are briefly described in this section. First , three actions, and two potentially complementary actions to stabilize salinity and flooding at the Sea are identified. Then the general characteristics of a program to control pollution are discussed.
A. Options to Stabilize Salinity and Sea Level
1. Pumpout / Desalination / Solar Generation
One alternative proposed for Salton Sea has involved pumpout of Sea water onto land, where it is evaporated, leaving saline residue. In a subsequent step, this residue could be utilized in a solar plant to generate electricity. Holdsworth (1987) estimates that slightly more than 100,000 acre feet per year would have to be pumped from the Sea under present conditions to stabilize both Sea salinity and Sea level, assuming a salinity target of 40,000 ppm. This would be achieved over about 70 years. At a salinity target of 45,000 ppm, stability could be achieved far more quickly, and likely with less pumping. The vertical evaporation process proposed by ORMAT to achieve this option brings the process within marginal land availabilities in the Salton Sea area. Construction costs for the full system would be expected to run in the order of perhaps $6 million for and, $72 million for the evaporation process and $25 million for generation of 25 MWT of solar energy or a total of about $100 million+. Feasibility work is presently being funded by IID, Imperial County and ORMAT ($100,000). A $10-12 million proposal for module testing has been submitted to state government.
2. A Saltwater Impoundment in Salton Sea
A 50 square mile diked impoundment in Salton Sea was the recommended solution of the 1974 Task Force. The dike would be a partially submerged continuous 37-mile long earth "dam" built on the Sea floor, with its shoreward side generally 112 to 1 mile from shore. The impoundment would encompass about 14 percent of the Sea's surface area and would last for about 100 years before it "filled up" with salt. It was estimated to achieve a salinity in the Sea of 35,000 ppm in 12 years. Updating estimated 1974 costs to 1986, this option would cost between $125 million and $155 million, with annual operating costs of about $1 million.
A smaller 40 square mile impoundment was estimated to return Sea salinity to 35,000 ppm within 18 years. It was estimated to cost, at most about $140 million, plus annual operating costs of about $600,000 (in 1986 dollars). These alternatives are still judged technically feasible today. Recent concern has been expressed regarding possible "leakage" from the impoundment into the Sea, and possible vulnerability to earthquake. These issues may -require further consideration.
This alternative has been extensively scoped in earlier technical analysis (see the 1974 Task Force Report). A decision needs to made whether to go forward with this and/or other options in 1990 (see subsequent schedule).
3. Gulf Waterway Option
In 1971, the Aerospace Corporation identified a plan to stabilize Salton Sea salinity and water level via a pumping capability to the Gulf of California. That proposal holds little benefit for Mexico, and is consequently not deemed feasible. A waterway with appropriate locks, to enable pleasure craft to travel back and forth between the Salton Sea and the ocean is, however, being considered as one present option. This solution would enable control of salinity And water level at Salton Sea, and unlike the canal/pipeline proposal would offer major potential infrastructural benefits to Mexico. It would also complement the expanding retirement/recreation complex in eastern Riverside County, and would provide the basis for a broad new tourism initiative based in Imperial County. This option is estimated to involve a construction cost of $250-$250 million. [The second figure should be $350 million - see Table 14 J.Dainer]. If it reaches the feasibility level, formal discussions and an eventual agreement-with Mexico would be required.
B. Supplementary Options
1. Colorado River Surges
It has been suggested that now that reservoirs on the Colorado River are full, surges of water will be released down the river in wet years, and could be made available to Salton Sea either through existing canals or via an expanded canal system. It will only be appropriate to consider this option after salinity targets are established and after a basic decision regarding the full option response has been reached (post-1990). Prior lowering of the Salton Sea's surface level would seem a prerequisite to avoid flooding. This option would entail periodic fluctuations in water level at Salton Sea, particularly in years when surges were delivered. It would likely require some form of entitlement agreement, either via the Colorado River Board, or in other form. Finally, the record of the past three decades indicates that dilution with Colorado River water cannot, by itself stabilize salinity levels at Salton Sea and keep Sea levels below flood stage. Consequently, any dilution alternative must be combined with enhanced evaporation and/or pumpout.
2. Pump-back of Brine Water to Yuma
If it is considered desirable to operate the evaporation process at a level beyond where the solar plant can utilize all brine produced, it may be necessary to dispose of excess brine. One possibility to do this could be construction of a pipeline back to Yuma and disposal of the brine in a Gulf of California drain established for such purpose as part of the Yuma desalination plant.
C. Dealing with Pollution at Salton Sea
Potential pollutants at Salton Sea cover a broad range of organic and inorganic agents. As noted, however, recent discussion and analysis has concentrated on cleanup of organic and inorganic pollutants from New River and Alamo River, and effective control of selenium. This provides the focus for our present report.
1. Cleanup of the New River
Cleanup of the New River is complicated by the fact that a significant portion of pollutant loading from the river comes from the Republic of Mexico (see previous). The United States and Mexico signed a 1983 U.S. - Mexico Border Environment Agreement, with EPA as the lead agency on this side of the border. Montgomery Consulting Engineers (1987) identified a number of structural alternatives for pollution abatement on the U.S. side of the border, for the California Regional Water Quality Control Board (RWQCB). The State Water Resource Control Board (SWRCB) is presently seeking funds to design a separating screen for gross solids and trash in the river, as well as to conduct other studies. A $1.2 million joint U.S./Mexico project directed at improved collection of waste in Mexicali has just come on line and this is a significant step toward improving the New River situation . Finally, RWQCB continues to monitor New River pollution, and Mexico is cooperating to enable measurement on their side of the border as well. Past improvement at New River has been slow, requiring collection of basic data and cooperative efforts by two nations. Steady improvement is expected to continue, the pace of that action depending on priorities and fiscal capabilities in both countries. In the United States, action is likely to focus on further monitoring, and on consideration of actual pollution abatement alternatives. These will, in turn, depend on decisions reached by SWRCB and EPA over the next several years.
2. Cleanup of the Alamo River
Pollution in the Alamo River is almost entirely generated in the United States. The RWQCB has commissioned a pesticide residue study for the drainage area and continues to pursue selenium issues (see below). Aside from these actions, there appears to be little momentum at either SWRCB or EPA levels. It would consequently appear that pollution issues in the Alamo River will be primarily addressed within the context of management of agricultural drainage.
3. Management of Selenium at Salton Sea
The RWQCB, in concert with the U.S. Geological Survey (USGS) has embarked on a study of selenium sources affecting the Salton Sea area. This study is focusing on tile drainage, soils and Colorado River water. IID is an active cooperator in this analysis.
EPA has recently published Ambient Water Quality Criteria for Selenium (1987) and has requested that the RWQCB incorporate a numerical water quality objective for selenium in its updated Water Quality Control Plan. At present, RWQCB believes that establishing "best practical farm management procedures" with respect to control of selenium will be more effective than a numerical standard. It is anticipated that discussive efforts to resolve this question will continue, with a decision in the first half of 1989. At this point in time, it seems likely that efforts to manage selenium effectively will continue with some sort of combed procedure targeting improved farm practice and eventual standard setting a possible outcome.
8. Programs Affecting Salton Sea
While problems at Salton Sea continue to the present, it is incorrect to conclude that no remedial efforts are underway. In fact, considerable effort is presently ongoing at the Sea. Table 11 summarizes ongoing programs, characterized by type and by agency. Readers should refer to the specific identified agencies for details of the programs identified here. Examinatin of the tdable suggests that to date, progressive efforts at the Sea have focussed on information gathering, with less attention directed to testing and devleopment of actual remedy.
1. Sea level monitoring l a. Monthly monitoring program l a. DWR 2. Flood control 2 a. Analysis of remedial flood control measures in the New
River and Alamo River drainages 2 a. Corps. 3. Pollution information gathering and monitoring 3 a. Periodic monitoring of Salton Sea, New River and Alamo
River water quality 3 a. DWR 3 b. Bioaccumulation of selenium in aquatic birds and diving
ducks 3 b. FWS 3 c. Drainage area pesticide residue study 3c. RWQCB 3 d. Selenium sources study re. Salton Sea 3d. USGS 4. Pollution control 4 a. Structural alternatives for pollution abatement in New
River (completed, 1987) 4 a. RWQCB 4 b. Improvements to the Mexicali sewage system (just on
line) 4 b. Mexico/US 4 c. Update of Region 7 Water Quality Control Plan (1989) RWQCB 5. Wildlife studies 5 a. Wildlife habitat and food studies 5 a. FWS 6. Fishery studies 6 a. Salinity tolerance of Salton Sea Sport Fishes 6 a. CF&G 6 b. Economic importance of the Salton Sea Sport Fishery 6 b. CF&G 7. Evaporation Ponds 7 a. Evaporation pond testproposal 7 a. IID 8. Pumpout/Evaporation/Solar
generator 8 a. Feasibility analysis 8 a. IID
Summary of Ongoing Programs at Salton
Sea
RWQCB
USGS
RWQCB
EPA
Imp. County
9. Options for Improvement of the Salton Sea
Analysis to this point allows us to reach to the following conclusions.- There is near unanimity among interested parties that the major beneficial uses at Salton Sea - namely agricultural, fishing, recreational and residential/retirement should be preserved and/or enhanced;
- Benefits from effective control of salinity, flooding and pollution of the Sea are worth at least hundreds of millions of dollars and appear to justify large scale remedial investment;
- Failure to effectively manage problems at Salton Sea will place severe pressure on those agencies/entities with legal responsibility at the Sea, as subsequent adverse events occur;
- Technical alternatives that would control salinity and flooding at the Sea, are available, and at estimated levels of cost that seem justified by expected benefits.
Despite these agreed interests, available remedial opportunities, increasing financial and legal risks associated with non-remedy and the significant levels of ongoing effort evident from Table 11, it can be fairly stated that no focused program for remedy has yet been developed. Development of such a focused options program will be the target for the balance of this report.
As noted, we conclude that failure to develop a focused options program for remedy at Salton Sea cannot be principally related to disagreement on objections (most parties agree), to the issue of whether potential remedial benefits would exceed costs (they do), or to whether general remedies are technically available (they are). Rather, we believe that lack of satisfactory progress to date has been chiefly related to four causal factors.
- a disparate process that has not always focused participants energy on central objectives and related critical programs;nificant uncertainty with res