While the constructed wetland method has been tried and tested elsewhere in the world, the Yarkon River will incorporate an innovative waste treatment method devised by Prof. Avner Adin from the Hebrew University of Jerusalem. As Earth Day was celebrated …
There are literally dozens of highly active green groups and organizations in Israel, both small and large, from Clean Air, to People Against Radiation, Environmental Bio-Architecture in Israel, the Tel Aviv Bike Support Group, the Society for the Protection of Nature in Israel, and Adam, Teva V’Din (Israel Union for Environmental Defense).
In recent years, Israeli academia has joined the advocacy community in taking a leadership role in pursuit of a cleaner and healthier environment. And in honor of Earth Day, many of the leaders of the environmental community convened at a conference at Tel Aviv University chaired by TAU’s Porter School of Environmental Studies (PSES).
The one-day event featured presentations on a wide range of cutting-edge environmental projects currently in progress in Israel. Prof. Gideon Dagan of TAU’s Faculty of Engineering, for example, presented a talk on Modeling the Salt Water Body in the Northern Part of the Yarkon River Aquifer, Prof. Dan Gerling discussed Ecological Interrelationships of Insects in Israeli Woodlands, and Prof. Eyal Ben Dor of the Department of Geography and Human Environment provided a whirlwind introduction to his work on Hyperspectral Remote Sensing for Monitoring of the Environment.
Following opening remarks by PSES head Prof. Zev Levin, Chief Scientist at the Israeli Ministry of the Environment Dr. Eli Stern offered an overview of the government’s efforts in green topics.
“There is an enormous amount of work being undertaken on environmental issues in Israel – both by the Ministry of the Environment and various green organizations,” said Stern.
Despite his gargantuan workload Stern was upbeat about the way environmental matters are developing in Israel. “We have a lot of areas to address, from the quality of the water we drink to radiation from cellular communications facilities and noise levels. But we are making good progress. For example, despite the large growth in the number of cars on our roads, pollution levels are increasing at a far slower rate that you would have expected. And, of course, we are investing heavily in trains. That also helps.”
Stern also referred to intensive efforts being made to clean up Israel’s waterways. “The Kishon River, for example, is much cleaner now than it was. There are far less heavy metals and other organic contaminants there today.”
As a small country with a growing population and developing industrial base the issue of green spaces – critical to the quality of air Israelis breathe – is also being addressed.
“Together with the Ministry of the Interior’s Planning Administration, we are setting out policy outlines to ensure that open spaces are safeguarded,” continued Stern. “We are also taking measures to protect our beaches.”
The latter objective is being furthered by legislation, currently making progress in the Knesset, to outlaw all construction on Israel’s beaches.
Dana Milstein and Prof. Avital Gasith from TAU’s Institute for Nature Conservation Research enlightened the conference audience as to how they are aiming to reduce pollution in one of Israel’s main waterways, the Yarkon River, that flows through Israel’s most heavily populated Gush Dan region near Tel Aviv and into the metropolis.
“The basis for our project stems from the fact that Israel has a water shortage problem,” explained Gasith. “We have short winters, a growing population and rising water consumption. We live in a region that is naturally green in the winter and spring, and dry in the summer. We, in Israel, are trying to create conditions like in North America and Europe and we use water for agriculture and for our gardens. We turn yellow landscapes into green ones, and there is fierce competition for water use between industry, agriculture and domestic needs. The losers in this race are the natural bodies for water collection, like rivers.”
The Yarkon River has been one of those losers for some time now and the drop in water flow has resulted in reduced water volumes and decreased ability to dilute pollution that finds its way into the river. Milstein and Gasith’s solution to this problem is to adapt the idea of wetlands, already used successfully in the United States and Europe, to filter polluting elements with vegetation.
“Until the 1950s the Yarkon River had an annual water volume of 220 million cubic meters. That volume has now dropped to 0.4 million cubic meters. I think that illustrates the severity of the problem,” said Gasith. That problem was further exacerbated by Israel’s industrial development that led to the pumping of industrial waste into the river.
“They say ‘the solution to pollution is dilution’, but I add that that’s an illusion. Israeli rivers don’t have the same water volumes, or dilution capabilities, as rivers in North America and Europe,” said Gasith.
Upgrading waste treatment at source – at the industrial plants that produce the polluting substances – has been proven to be economically non-viable so a different solution was sought.
“We decided to adapt a biological method of treating the waste that has been around in the world for about forty years – constructed wetlands,” said Gasith.
While the theory sounded fine, Gasith and his colleagues had to tackle another logistical problem – the lack of space in a small country such as Israel.
“In San Francisco they have an enormous wetland but we don’t have the luxury of space. We decided to go for a concentrated solution by using modular constructed wetland pools with gravel of different sizes and a variety of vegetation capable of filtering out the industrial waste. After a while biofilm develops on the gravel and this breaks down the waste so it can be subsequently diluted by the river,” said Gasith.
Gasith and Milstein are overseeing the inauguration and operation of a 2.5 dunam (approx. 0.6 acres) pilot constructed wetland area. “The wetlands will be sited near the Kanna River which is the prime source of waste flowing into the Yarkon River. Ultimately, we plan to implement constructed wetlands covering an area of 50-60 dunams (approx. 12-15 acres).”
While the constructed wetland method has been tried and tested elsewhere in the world, Gasith explained that the Yarkon River will incorporate an innovative waste treatment method devised by Prof. Avner Adin from the Hebrew University of Jerusalem.
“Our wetlands will use Prof. Adin’s technique based on a electrochemical process – called electro-flocculation – that causes miniscule particles, that don’t sink into the wetlands gravel and which can’t be treated per se, to group together to form larger particles that do sink or that can be treated. This greatly enhances the water quality,” said Gasith.
For his part, PSES head Prof. Levin is sensitive to the importance of disseminating knowledge on environmental issues as widely as possible. “Our job, as a university, is to produce objective and accurate information so that green organizations, government ministries and the public can work on the basis of scientific facts and figures. We want to get away from the ivory tower image and make the information more accessible.”
The PSES, which was founded in December 2002, adopts an integrated multidisciplinary approach looking at scientific, technological, social, political, economic and ethical aspects of ecological areas. The school collaborates with municipal authorities, and government and non-government authorities, and has struck up a fruitful partnership with the Italian government. The Italian-Israeli Forum on Environmental Technologies, established in 2002, promotes binational collaboration and the exchange of scientific and academic expertise in the fields of the treatment of water, solid waste and air quality.
“We have received a grant of 1.5 million euro from the Italian Ministry of the Environment to develop six research projects,” added Levin. “We are looking into river and land rehabilitation, desertification and forecasting urban air pollution levels, and making houses self-sufficient in terms of their heating and energy requirements.”
Like Stern, Levin is optimistic about the future of Israel’s environment. “We are getting the word out there, to teachers, students, companies and the general public. Green issues were central to many campaigns in the last municipal elections and it wouldn’t have been possible to establish something like the PSES twenty years ago. Things are definitely improving.”