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THE NATIONAL CARRIER: THE ENVIRONMENTAL UPSHOT

There were serious water quality problems associated with the National Carrier, most of which were solved by Mekorot's engineers. By far the most significant was the salinity of the water, caused by the salty springs that drained into the Kinneret. In 1964 salinity levels in the lake were measured at 390 milligrams per liter of chlorine (chloride ions).[70](Although Israel's drinking water standard allows chlorine to reach con-centrations of 600 milligrams per liter, it recommends 250 milligrams per liter to reduce the risk of hypertension and improve the taste.) In response, Tahal planned a Saline Carrier that collected the flow of the surrounding saline springs and released them into the Jordan River, south of the lake. Chlorine levels in the Kinneret were immediately cut in half and now measure roughly 200 milligrams per liter, a far more acceptable level.[71]


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The Saline Carrier was among the many areas of disagreement with Blass, who insisted that the saline streams' diversion precede all other work (he was overruled, and as a result from 1964 to 1967 Tel Aviv's drinking water was very salty[72]). Even after the diversion, the high chloride content of the Kinneret posed a problem for irrigation. Mekorot responded with a system that diluted the water in transit by injecting clean, low-chloride water into the flow from the lake.[73]

In addition, from its survey during the 1950s, the Ministry of Health was already aware of high levels of coliform bacteria in the Jordan. This was primarily attributed to the runoff from dairies and fishponds (manure is a relatively popular fish food). Chlorination is the standard treatment, but it poses other risks. Chloroform and other trihalomethanes are created in water when organic sediments mix with chlorine gas. These compounds are some of the unfortunate by-products of disinfection and are associated with cancer of the liver.[74] (Given the levels of suspended solids in the Kinneret, it was no surprise when trihalomethanes were discovered in Israeli drinking water.[75]) To make matters worse, the Kinneret has a rela-tively high bromide level (two parts per million), which, when chlorinated, oxidizes to become active bromine. The bromination of these organic ma-terials may pose an even more significant carcinogenic risk.[76]

Even if the cancer risk levels are disputed, the sediments alone created a serious turbidity problem. During the winter months, the Jordan River can turn a dark cocoa-brown from runoff. In those days, the Ministry of Health measured turbidity according to Jackson turbidity units (JTUs), with the benchmark (as opposed to legal) standard set at 10 JTUs. Today, the allowable level has dropped 1000 percent, corresponding to 1 JTU. After rainstorms, however, frequently even the 10-JTU standard could not be met, and turbidity levels went into the thousands, leaving the water unfit for human consumption.[77] This produced the naturally corrosive conditions and murky waters found downstream in the Kinneret.[78]

These factors determined Israel's treatment strategy for the waters de-livered to the south. The Ministry of Health ordered that the Carrier in-clude treatment by coagulation and sedimentation along with chlorination to reduce the pollutant concentrations. No one had any experience in a project this size, so Ben Nessen, the Chief Water Quality Engineer from New York City, was brought over to Israel to help prepare the treatment plan.[79] Nessen's disinfection strategy has changed little in thirty years.[80]

Israel took a chemical rather than a biological approach to drinking-water treatment. For instance, Mekorot engineers for years were nervous about introducing fish into the National Carrier reservoirs as part of the


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water's biological treatment. They still had not gotten over the surprise of 1959, when consumers in the south found tiny fish flowing from their taps (the fish had swum out of a reservoir built as a section of the Yarkon-Negev line[81]). By the end of the 1970s, however, evidence of the beneficial properties of fish was compelling. Fish were introduced into the Eshkol Reservoir to eat algae, snails, and other small aquatic creatures, which they devour voraciously.[82]

In evaluating the impacts of Israel's national water system, there is ul-timately no single environmental bottom line. It certainly hurt the Dead Sea. Without the Kinneret spillover, the saltwater lake quickly began to shrink, producing an unsightly naked shoreline and reducing the attrac-tiveness of the recreational experience.[83] Lake Kinneret itself shows mixed trends. Although salinity dropped, other parameters, such as nu-trients, rose. To ensure water quality, the carrier withdraws water at a rel-atively shallow intake that is low in nutrients. This increases the Kinneret's overall concentration of ammonia and sulfides and over the long term may exacerbate the eutrophication or aging processes.[84] Nitrogen, rather than phosphorus, was identified as the nutrient most linked to this phenomenon.[85]

The Carrier made the entire country dependent upon Lake Kinneret's water quality, elevating its preservation to a national priority. During the winter months, newspapers post the level of the lake in their front sections alongside weather forecasts, where it is followed with a devotion otherwise reserved for the standings of the National Soccer League. While far from being springwater, the quality of Lake Kinneret water is reasonable.[86]

The alternatives may have been worse. Blass's impatience was not based solely on the need to expand agriculture but also on the overpumping and rapid salination of the Coastal Aquifer. Groundwater is less subject to re-medial measures than the Kinneret. “The powers-that-be thought that I was only trying to scare them,” he later wrote. “The fact is that by the time the Carrier went on-line, there was already a deficit of 500 million cubic meters along the coastline.”[87]


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