The Jordan Valley with its great amount of greenhouses is the main producer of vegetables and fruits of the kingdom. Water in this region is scarce, so one of the main tasks of the Jordan Valley Authority (JVA) is to manage this precious resource to obtain the best possible yield in agriculture. Jordan River itself transports only little water, which most of the time can’t be used for agriculture because of its high salinity.
The freshwater comes mainly from the Yarmouk River in the north, coming from the Syrian highlands and some other Jordan River tributaries. It is transported through the King Abdullah Canal to the south. Most of this water is then pumped up to Amman, where it is treated and supplied into the drinking water system. This water is then, after use and treatment at the Khirbet As-samra waste water treatment plant (WWTP), stocked in the King Talal reservoir and returns to the Jordan Valley, where it is used for irrigation.
Irrigation by wastewater has increased by 10% during the last two years, and the goal the JVA would like to attain is to cover the maximum possible of the agricultural needs, especially as the amount of freshwater coming from Syria is drastically diminishing. Currently there is not enough wastewater to cover all the needs, but it’s expected to be in about 10 years. Because of the water scarcity, the actual demand can’t be met. Therefore most farmers get only 45-60% of the water required.
To avoid the pathogenic contamination of those vegetables which are eaten uncooked, like tomatoes and cucumbers, the water quality is monitored. Weekly samples are taken randomly at different irrigation stations and their E.coli concentration is analysed.
Grey Water Reuse in the Dead Sea Spa Hotel
In Jordan, the Dead Sea has become more and more touristic over the last decades and a lot of new hotels have been built along the cost. This trend is most probably going to continue in the future. As the water scarcity is a very important issue in this area it is very important to use and reuse this valuable resource in the most efficient way possible.
The Dead Sea Spa Hotel has been the first in the area to come out with an interesting and promising solution of in-house grey water reuse. This project has been done in cooperation with the German International Cooperation. Grey water can be defined as the wastewater generated from domestic activities such as bathing or laundry which doesn’t containe any fecal matter. Sewage water from toilets doesn’t count as grey water. The principle of grey water reuse can be applied at different levels: for rural and urban systems or for large volumes. The grey water can be treated and then reused for different applications but in most of the cases it is done for irrigation, toilet flushing and cleaning. The need for water of drinking quality (mainly for drinking, cooking, and bathing) represents only 50% of the total water consumption. The remaining 50% don’t need such high quality and could therefore been supplied with grey water. In order to install a system of grey water reuse, two piping systems are needed: one to supply drinking water and to collect the grey water and the other to supply grey and to collect the sewage water (see figure below).
In the Dead Sea Spa Hotel, the grey water is reused for irrigation as well as for the toilet flushing and floor cleaning. The water is used 3 times, first the freshwater is used for the showers, then grey water is reused for the toilet flushing and then the sewage waste water is treated in the on-site Waste Water Treatment Plant and is reused for irrigation. This 3 steps in-house grey water reuse is a new concept in Jordan. The freshwater is supplied to the Dead Sea Spa Hotel by 10-12 tankers per day, and it is used for different purposes mainly for the shower and baths. The grey water is then collected and treated to a very high quality level and is reused for the different activities listed above which do not need freshwater. The treatment process is divided in several steps. Firstly there is a mechanical filter in order to remove all solid particles like hairs or sand from the grey water. Then the water is treated in a 2-step biological process where tanks are filled with sponge cubes acting as carriers for microorganisms. After that, the water is sent through a sand filter and is finally disinfected with UV. At the end of the treatment, the water reaches the goals in terms of quality of the European Directive for Bathing Water.
The system that have been installed in the Dead Sea Spa Hotel has a payback time of 11 years and the potential of water savings is about 17%of the total water consumption. This system has different benefits such as reducing the waste water amount and therefore reducing the size of the on-site WWTP, reducing the dependence on external water supply or improving the quality of irrigation water.
Silvia Oppliger, Nicolas Fülleman et Vincent Genicoud
Sources : Rothenberger Silke, In-House Greywater Reuse for Large Volume Consumers in Jordan, PPP at the Dead Sea Spa Hotel, 2011 and http://www.jica.go.jp/iraq/english/activities/pdf/training06_01.pdf
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