Effects of Dumping Sewage Water Directly Into the Sea, A Project by Students in Saida, Lebanon WHY
DID WE CHOOSE THIS PROJECT? Effects
of Water Pollution:
WHAT
IS DOMESTIC SEWAGE? WHY IS DOMESTIC SEWAGE A PROBLEM? Domestic
sewage contains a wide variety of dissolved and suspended impurities.
It amounts to a very small fraction of the sewage by weight, but it is
large by volume and contains impurities such as organic materials and
plant nutrients that tend to rot. The main organic materials are food
and vegetable wastes. Plant nutrients come from chemical soaps, washing
powders, etc. Domestic sewage is also very likely to contain disease-causing
microbes. The various substances that we use for keeping our houses clean
add to water pollution because they contain harmful chemicals. Most detergents
and washing powders contain phosphates which are used to soften the water,
among other things. These and other chemicals contained in washing powders
affect the health of all forms of life in the water. Ecological Damage: Sewage-contaminated water causes eutrophication, which is the increase in concentration of chemical elements required for life. The nitrates, phosphates, and organic matter found in human waste serves as a food for algae and bacteria. This causes these organisms to overpopulate to the point where they use up most of the dissolved oxygen that is naturally found in water, making it difficult for other organisms in this aquatic environment to live. The bacteria are basically strangling the other organisms. Some of the organisms that do overpopulate from this can also be disease-causing microorganisms. Phosphates are also found in soaps and detergents, but there are other household products that we use everyday that can be toxic to many animals and humans if they are dumped directly into a water body.
Health Risks: Bathers are at increased risk of contracting illness due to bacteria and viruses present in sewage effluent. Gastrointestinal disorders have been linked to sewage pollution, with viruses implicated as the cause. Shellfish strain water through their gills to trap microscopic plants and animals for food. If the water was contaminated with disease-causing bacteria, these could be consumed as food by shellfish. When eaten raw or partially cooked, these shellfish can make people sick. Certain fish in contaminated waters can accumulate high levels of toxic substances. When these foods are consumed frequently over a lifetime, they may increase the consumers’ risk of adverse health effects. Detergents can cause liver and kidney damage, while sewage water carries diseases such as Giardiasis, Amoebic dysentery and Cholera. Economic Loss: Debris associated with sewage probably has the highest monetary cost associated with its presence on our beaches due to the resulting loss of tourism in addition to blockage removal. The closing of commercial shellfish beds due to sewage contamination can lead to high income loss. Clean
beaches have many advantages for humans and commercial seafood farms as
well as for the wildlife:
WHAT IS THE SOLUTION? It used to be said that “the solution to pollution is dilution.” When small amounts of sewage are discharged into a flowing body of water, a natural process of stream self-purification occurs. However, densely populated communities generate such large quantities of sewage that dilution alone does not prevent pollution. Instead of discharging sewage directly into a nearby body of water, it’s better to let it pass through a combination of physical, biological, and chemical processes that remove some or most of the pollutants. This takes place in sewage treatment plants. Treatment Plant: Sewage treatment plants neutralize and deactivate the chemicals found in the sewage water. They work by relying on the bacteria that is found in our colons, which eat away the nitrates, phosphates and organic matter that is found in sewage. These plants can be expensive to build and operate for many governments, but there are cheaper alternative which rely on nature to do most of the work. This is done by rebuilding or restoring wetlands, because the plants and bacteria found in the wetlands will do the same thing that bacteria in standard sewage treatment plants do. This helps the environment in two ways: restoring wetlands and treating human waste water before it pollutes the natural waterways. WHAT CAN CHILDREN DO? In many countries, there is an ongoing national campaign called ‘Bag it and bin it, don’t flush it!’ It’s aim is to protect rivers and seas by decreasing the number of disposable items flushed down toilets. So, bag it and bin it. Please don’t flush it. Don’t flush anything down the toilet that is made of plastic or non-biodegradable material. This includes cotton bud sticks, sanitary towels and nappkins which can travel through the sewers and end up back on our beaches. WHAT DID WE DO? We knew that recently the government had made a sewage treatment plant in Khaldeh. We wondered why we shouldn’t have one in Saida as well. That’s why we visited the head of the municipality, Hilal Koubrossli, to discuss the issue. This is a summary of the meeting: Mr. Hilal Koubrosli welcomed us in his office. We told him about our project. We showed him the pictures we had taken. Then we gave him a summary of our research. We informed him that the purpose of our visit was to see if there is any plan to solve/reduce this problem. He told us that there are 16 pipes of domestic sewage that are discharged directly into Saida’s seashore He went on to say that the municipality has beenworking on a project for six months to deal with this problem. The project concentrates on both solid & liquid wastes.The plant will be ready within two years. He also informed us that wastewater may be reclaimed & reused for crops etc.
RESOURCES - Biology and Geo Science Dept. Stuyvesant High School. - www.soton.ac.uk/engenvir/environment/water/beach 6.htm - Britannica - www.wsugreen.teri.res.in/explore/water/pollu/htm -www.mcsuk.org/marineworld/sewage - www.mede.State.md.us/enpa/2000 - www.anarac.com/water-pollution.htm Zeina Hariri, Rola Khlifa, Mohammad Atalla and all Grade 7 B students at Houssam Hariri High School submitted insightful questions and comments about this project. To learn more, email Eliane Metni at pcmelo@emetni.com
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