Congress and EPA Propose Solutions to Southwestern River Salinity

Two recent developments give rise to optimism in the effort to improve water quality in the southwestern United States. Both the passage of the Colorado River Basin Salinity Control Act of 1974¹ and a proposal by the Environmental Protection Agency for the establishment of a salinity control program in that same basin² tackle what has sometimes been considered an insurmountable interstate and international problem.

The Colorado River is a major North American river with a watershed of over 244,000 square miles in the United States and the Republic of Mexico. Its 1,450 mile length drains parts of Arizona, Colorado, New Mexico, Utah, Wyoming, Nevada, California, and Mexico. Much of the river is an agricultural-use watercourse, but the Colorado also is a major source of water to satisfy the municipal and industrial needs of nearly 10 million people in the Los Angeles-San Diego metropolitan area. It has been said that the Colorado River "is undoubtedly the Pacific Southwest's most valuable material resource."³

When water is taken from a river, distributed over croplands, and allowed to seep back into the river or into local subsurface aquifers, it takes with it salts (dissolved minerals) leached from the soil. Evaporation takes place as water flows in the river or passes along open irrigation ditches, leaving a higher concentration of salts behind. These two problems — salt loading and salt concentration — are a passive type of pollution; their source is impossible to pinpoint, and they may occur to some extent when even the most conscientious irrigation techniques are used.

Irrigators can take steps to minimize the amount of stream salinization that results from their activities. They can line irrigation canals with concrete to reduce leakage and seepage, utilize covered waterways or pipes rather than open ditches to reduce evaporative loss, or carefully manage their water use, for excess water distribution means unnecessary salt leaching. Poor water management can allow large amounts of irrigation water to enter the subsurface aquifers of the area, increasing the salinity of that resource and eventually raising the level of the now-saline ground waters dangerously close to the root zone. When that happens, irrigators must actively pump out the subsurface aquifer to lower the water table, and maintain pumping to compensate for the effect of continued irrigation. Pumping should be combined with steps to ensure that future crops are not given more water than they can consume.

Of course, irrigators are not the sole contributors to high stream salinity.For example, ski areas can damage stream ecology by pouring tons of salts onto ski slope snow to keep it soft and useable into spring and summer, and municipal water use can also increase dissolved mineral content. Natural sources of salinity, such as hot springs, geysers, and rain runoff from non-agricultural land may contributes as much as half of the total dissolved solids in the Colorado River.

Diffuse source mineral salt pollution has proven troublesome. Water that is too high in dissolved salts is not suitable for irrigation, and may be an unfit municipal water source. Different species of aquatic life vary in their tolerance to high salinity levels; some species require different salinity at different stages of their life cycles, and will migrate to find the proper level. The salinity levels in estuarine areas are dependent upon natural balances between fresh water inputs of rivers, streams and runoff, and salt water inputs from the ocean. If the salinity of fresh water inputs is altered, estuarine life may suffer. It has been found that while oysters are not highly sensitive to salinity levels, oyster drills, a predator, thrive on high salt content and will decimate the oyster population when dissolved minerals increase. Other beneficial species may be killed outright by salinity fluctuation.

The Republic of Mexico has long voiced distress over the salinity of water flowing to Mexico from the Colorado River Basin. In 1961 the salinity of waters made available to Mexico in the Colorado River was at an annual average of 800 parts per million, about half of that from man-made sources. In that year, pumping of highly saline drainage from the Wellton-Mohawk Irrigation District in Arizona into the Colorado River began. This input of [4 ELR 10144] waters containing approximately 6000 parts per million of total dissolved solids, combined with a reduction in the amount of water supplied to Mexico brought about by other factors, caused the salinity of waters supplied to Mexico to jump to nearly 1500 parts per million. In November of 1961 the Mexican government protested vigorously to the State Department, and serious efforts toward finding a solution began. International negotiations led to treaty modifications; some reduction in salinity was achieved by diversion of Wellton-Mohawk discharges, but until recently no major comprehensive salinity control programs were initiated.

The first recent step in Colorado River salinity control came on June 10, 1974, when the Environmental Protection Agency proposed "amendments to 40 CFR part 120, to set forth a salinity control policy and procedures and requirements for establishing water quality standards for salinity and a plan of implementation for salinity control in the Colorado River System …"⁴ The proposed standards would be promulgated pursuant to the Federal Water Pollution Control Act, and would be adopted by the states involved, in much the same manner as any other federal water pollutant standards. The proposed rule requires the states of the Colorado River Basin to adopt water quality standards for salinity, including numeric criteria, consistent with maintaining salinity at or below 1972 levels, and to submit a plan to EPA for achievement of compliance with those standards. The goal of the plans shall be to attain compliance with the adopted standards by July 1, 1983. Thus, if promulgated, the rule would seek to enforce a non-degradation policy based on 1972 river salinity levels.

The second big step in multi-state river salinity control came when President Nixon signed the Colorado River Basin Salinity Control Act into law on June 24, 1974. Title I of that Act provides for a desalting complex to treat the drainage waters from the Wellton-Mohawk project. The complex would process one hundred and twenty-nine million gallons of water a day, removing 90 percent of the dissolved solids in the feed water and effecting recovery of at least 70 percent of the input as product water. This complex and other smaller related projects would be built primarily to enable the United States to meet treaty obligations with Mexico regarding water quality.⁵ The estimated $154.5 million tab for the complex and associated works is to be picked up by the federal government.

Title II of the Act provides for several upstream salinity control facilities. Four major facilities would be built to collect and dispose of saline ground water, reduce irrigation system seepage, and control saline geyser discharges. These projects are designed to meet the long-range needs of the basin, and are probably the same types of actions and projects that would be included in state plans for compliance submitted to the EPA under its proposed regulations. The title also calls for expeditious completion of water quality improvement reports currently still in the research stage. Seventy-five percent of the estimated $125.1 million cost of these upstream developments will be funded by the United States. The other 25 percent will be paid out of ColoradoRiver Basin funds, which are revenues collected in connection with the operation of Colorado River water storage and distribution projects.⁶

Both the Act and EPA's proposed rule are designed to support and implement the conclusions and recommendations adopted on April 27, 1972, by the reconvened 7th Session of the Conference in the Matter of Pollution of the Interstate Waters of the Colorado River and its Tributaries. Though the Act and rule both share this connection, they are legally independent. EPA's proposed rule is based on the Federal Water Pollution Control Act; the Salinity Control Act is an entirely separate piece of legislation. The two actions could blend well in practice, however; the federal salinity control measures of the Act should make it easier for states to achieve non-degradation and set an example for the states to follow in formulating a compliance plan. The EPA standards may be viewed as a holding action whose potentially growth-restrictive impact is moderated by the "elbow room" that federal salinity removal creates.

A number of unanswered questions do still exist, however, any of which could impair the success of salinity control. The most basic question is whether the proposed EPA rule will ever be promulgated. It might appear that states could chafe under the anticipated burden of one more pollution control plan, preventing the rule from surviving the comment and review procedure that precedes actual promulgation. However, the EPA reports that it has worked closely with the concerned states in drafting the rule, and unless unexpected opposition develops at public hearings,⁷ the rule should be formally promulgated without delay.

If the rule is promulgated, its effectiveness might be reduced by the fact that EPA has chosen to maintain a 1972-level non-degradation standard instead of seeking stricter criteria. Salinity in the Colorado River Basin was a matter for concern long before 1972; non-degradation standards only endorse maintenance of an unsatisfactory salinity level. In 1945, the salinity at Imperial Dam on the [4 ELR 10145] Lower Colorado was 701 parts per million (ppm); in 1955, a drought year when salinity would be unusually high, the level was 795 ppm; by 1965, the level had risen to 894 ppm.⁸ Salinity at the border with Mexico is higher than that at Imperial Dam because of the downstream Wellton-Mohawk discharges. Although the Wellton-Mohawk salinity input has decreased significantly over the years, in 1966 water at the border contained 1240 ppm; current border levels are estimated to be around 1000 ppm, raised to that figure by Wellton-Mohawk discharges of about 3100 ppm.

Obviously there is room for improvement in the current salinity situation, even though Colorado River states consider any standards to be growth-restrictive, and predict economic disaster whenever active cleanup is mentioned. A compromise non-degradation standard hardly seems in keeping with EPA's duty under theFederal Water Pollution Control Act Amendments of 1972 to "develop comprehensive programs for preventing, reducing, or eliminating the pollution of the navigable waters and groundwaters and improving the sanitary condition of surface and underground waters" (emphasis added).⁹ The proposed rule seems rather too accommodating to political problems.

The Salinity Control Act also has its troublesome aspects. There are considerable grounds for objection to government assumption of so great a share of the costs of this cleanup effort. Admittedly, salt loading has not always been recognized as a practice which water users have a duty to avoid, but apportionment of the costs of salinity control to Colorado River water users might seem more in line with a general policy of imposing cleanup costs on those who cause the contamination. The inconsistency of massive federal funding is heightened by the fact that some of the Act's projects will include "on-farm" improvements, such as concrete lining of a private farmer's canals.

The Act states its cost assumption to be "in recognition of Federal responsibility for the Colorado River as an interstate stream and for international comity with Mexico, Federal ownership of the lands of the Colorado River Basin from which most of the dissolved solids originate, and the policy embodied in the Federal Water Pollution Control Act Amendments of 1972…".¹⁰ Such a rationale for federal cost assumption is faulty in several respects. The United States has entered into a number of international treaties that place the cost of pollution prevention or cleanup on individual offenders.¹¹ The United States does not, for example, plan to bear the expenses of pollution abatement in the Great Lakes, although the cleanup is pursuant to bilateral treaty.¹²

Federal ownership of lands in the basin is an equally weak premise upon which to base fiscal responsibility; the natural salinity contribution from these lands has always existed and always will. It is clearly distinguishable from the aggravation of saline pollution by irrigation and municipal water use which has unacceptably raised salinity levels. Federal land ownership would provide logical grounds for cost assumption only if the government engaged in extensive irrigation, or if salinity levels were to be reduced below natural "background" levels. In the absence of such ambitions, cleanup expense is more closely related to water use than to land ownership.

Russell E. Train, Administrator of the Environmental Protection Agency, has stated that the Act's reference to the 75 percent federal assistance policy embodied in the Federal Water Pollution Control Act Amendments of 1972 "is misleading because the construction grant provisions of those Amendments provide Federal funds only for assistance in construction of municipal waste treatment plants, and thus do not present a situation analogous to the Colorado River salinity control projects."¹³

The reasons advanced by the Congress for federal cost assumption do not seem persuasive. A more rational cost apportionment policy would recognize that present difficulties stem from man-made intensification of natural salinity problems, and would seek to allocate cleanup costs to those who have aggravated the problem. United States government figures indicate that 70 percent of man-made salinity in the Colorado River Basin is contributed by irrigation, 22 percent is from reservoir evaporation, 2 percent from municipal and industrial use, and 6 percent is a result of water exports out of the basin.¹⁴ Those who use waters from the basin do so under diversion permits or water right certificates; the task of identifying users and their proportionate share of costs would not be insurmountable.

Clearly, under the Act, non-federal water users would seem to be bearing less than their fair share of cleanup costs. This discrepancy is enlarged by the fact that the Colorado River Basin funds that are relied on for the non-federal 25 percent funding are not closely tied to water use. These funds are derived from revenues paid by those who consume power from federal hydroelectric facilities. In effect, the private sector funding of Colorado River [4 ELR 10146] salinity reduction may come from urban power users who contribute very little to the salinity problem.

When President Nixon signed the Act into law, he commented on his disappointment with the provisions for federal funding, and also noted that the Title II projects "may be premature at this time."¹⁵ The charge of prematurity was based on a desire for completion of state assessments of natural or diffuse sources of water pollution prior to implementation of expensive abatement procedures. The Act does call for expeditious completion of Colorado River Water Improvement Program planning reports, but there is an evident conflict between the need for immediate action and the desirability of careful advance planning.

In short, the decision by EPA to demand only non-degradation standards reduces the potential impact of their proposed rule, and the cost allotment system of the Colorado River Basin Salinity Control Act seems inconsistent with recognized need to impose cleanup costs on those who necessitate the effort. Nevertheless, these flaws, even when combined with objections of premature action, should not obscure the importance of what is being done. The two developments are significant steps toward control of a major water contaminant, and demonstrate long overdue high level concern for a serious interstate and international problem. It is far too early to say that a comprehensive program for control of Colorado River Basin salinity exists, but at least some initial steps have been taken. Hopefully, future government efforts at curbing salinity in this and other river basins will seek progress rather than a maintenance of the status quo, and will place the costs on the same shoulders that bear the blame.

1. Act of June 24, 1974, Pub. L. 93-320, 88 Stat. 266.

2. "Colorado River System Salinity Control Policy and Standards Procedures," 39 Fed. Reg. 20703 (1974).

3. "Report of the President's Special Representative for Resolution of the Colorado River Salinity Problem with Mexico," as reproduced in S. Rep. No. 93-906, 93rd Cong., 2nd Sess. 42 (1974).

4. 39 Fed. Reg. 20703 (1974).

5. Water quality obligations pertaining to the Colorado, Rio Grande, and Tiajuana Rivers arise under Minute No. 242 of the International Boundary & Water Commission, concluded under the Water Treaty of 1944, 59 Stat. 1219 (1945), T.S. No. 994.

6. The Colorado River Storage Project, 43 U.S.C. § 620 et seq. (1970); specifically, The Upper Colorado River Basin Fund, 43 U.S.C. § 620d (1970), and the Lower Colorado River Basin Development Fund, 43 U.S.C. § 1543 (1970).

7. Public hearings scheduled for August 19, 1974 in Las Vegas, Nevada, and August 21, 1974 in Denver, Colorado have not yet been held as this comment goes to press.

8. Figures provided by the Environmental Protection Agency.

9. P.L. 92-500, 86 Stat. 816, 33 U.S.C. §§ 1152 (d), 4 ELR 41101.

10. Act of June 24, 1974, supra, n. 1, § 205 (a) (1).

11. For example, the 1954 Convention for the Prevention of Pollution of the Sea by Oil, as amended in 1962, 1969, and 1971 gives ship owners responsibilities relating to oil discharge prevention, record keeping, and ship construction techniques. There are forty-eight signatory nations, including the United States.

12. 1972 Agreement between the United States and Canada on Great Lakes Water Quality, Art. V.

13. S. Rep. No. 93-906, 93rd Cong., 2nd Sess. 30 (1974).

14. S. Rep. No. 93-906, supra, n. 13, at 42-43.

15. 10 Pres. Doc. 717 (1974).