Two-thirds of Tel Aviv’s water wells are too polluted to use.
A recent study discovered that many Tel Aviv wells are polluted beyond suitability as drinking water sources. Data collected by the Health Ministry and Water Authority showed that 96 of a total 166 wells in the Tel Aviv area were closed due to contamination. Nearly two-thirds of the wells have been shuttered since 1980, when all 166 were in full operation. The pollution has been caused by two types of activities. First, contaminants from armament manufacturing, agricultural runoff and sewage systems seep into the groundwater table.
Second, seawater intrusion has caused salinity levels to rise. Coastal aquifers have built-in brackish water barriers that create a line between seawater and freshwater. When wells are overpumped, that barrier weakens and seawater flows into the aquifer. The subsequent spike in salinity is pervasive and difficult to remediate.
The Israel Military Industries site in Ramat Hasharon is the source of perchlorate leakage. Perchlorate is a rocket propellant used in several types of military equipment. It affects human health by interfering with thyroid function. It may also be a carcinogen, though studies have been inconclusive.
When perchlorate was discovered in Ramat HaSharon, residents immediately began receiving water from the National Water Company. Now the town has filed suit against the government for additional costs incurred due to the contamination.
The perchlorate must be remediated. That includes pumping the water out and purifying it. The plan will take 20 years and cost Israeli taxpayers half a billion shekels. But the cleanup is essential to ensure wells are fully restored and the perchlorate does not continue to spread.
Runoff from agricultural areas has been pervasive in the Tel Aviv area. Chemical pesticides and fertilizers used on most large-scale farms have leached into groundwater. This causes unacceptable levels of nitrates, which are a danger for both human health and the environment. 32 of the abandoned wells showed nitrate levels exceeding water quality standards. Additionally, several wells contain toxic metals.
Unfortunately, the problems with these wells started long ago. As Dr. Alon Tal notes in his book Pollution in a Promised Land, “it was not just overpumping and salinity that forced Tel Aviv to close its wells during the early 1950s. The city’s ubiquitous septic tanks leaked into the wellheads…[and] when Tel Aviv’s wells became too salty for drinking in the mid-1950s, it was a harbinger of things to come.”
These problems started long ago. They are symptoms of Israel’s water woes. An increasingly burdened distribution system, rampant sewage leaks, and agricultural runoff have been part of the country’s water narrative for decades.
And the crisis is not limited to the Tel Aviv area. Seawater intrusion has reached epidemic levels in the south of Israel. Mekorot, the National Water Company, is developing a plan to restore aquifers near Sderot.
The proposal involves building two brackish groundwater desalination plants at a cost of $150 million. These facilities will eventually produce thousands of cubic meters of fresh water that will be pumped to towns throughout the country. And the added benefit will be to ease seawater pressure on the aquifer. Moreover, brackish groundwater desalination has fewer impacts on the environment than other types of desalination.
Prof. Dan Zaslavsky of the Technion University has said that desalination’s ability to prevent seawater intrusion makes its development a necessity. He argues that in the past, when experts considered the economics of desalination, they did not factor in the costs of remediating aquifers in the absence of desalination.
But what about the perchlorate, toxic metals, sewage and agricultural runoff? Certainly Mr. Zaslavsky or others can make a convincing argument for instituting controls on those contaminants before they reach our aquifers. Because once they are in the water, only a prohibitively expensive remediation project will get them out.
Image via Rain Rannu
