Sazlıdere basin water quality, cost optimizations of waste water treatment and evaluation of wetlands cost

ABSTRACTSeven streams in Istrancalar and Sazlıdere dam were completed between 1995-1998 to meetthe water need in Istanbul, especially in the European part of Istanbul. Supplied fromSazlıdere Dam 55 milion m3 per year will be added to seven creeks carrying 235 million m3water per year that comes from Istrancalar, therefor total amount of water will reach 290million m3 per year. Raw water of Sazlıdere dam will be treated in Fatih Sultan Mehmet Handrinking water treatment plant, and will be sent to network. Millions of citizens living inK.Çekmece, Bağcılar, Bahçelievler, Bakırköy, Güngören, Esenler, Gaziosmanpaşa,Bayrampaşa, Eyüp, in Istanbul, will take advantage of this facility.In this study, available water quality of Sazlıdere water basin is tried to be determined withavailable data. Parameters of water quality data in Sazlıdere Reservoir can only provide mostof the first and the second class criterias for inland waters in terms of concentration. It can beseen that water quality in the streams feeding Sazlıdere Lake are heading for third and fourthclass criterias. The main reasons of deterioration of water qualilty is the wastewater comingfrom houses in the area.In this study, firstly the point and diffuse sources causing pollution in Sazlıdere Reservoir aretried to be determined. For this reason, in-situ etüd and studies are utilized as well asliterature. Pollutation sources caused by settlements is correctly determined only by takingaccount into land use and population projections. However, literature survey was carried outto determine pollutation loads from agricultural and forest areas. For industries locating in thebasin, wastewater loads leading to the dam is tried to be determined by the water quality data.In the next step, because a danger of eutrophication was determined as a result of theevaluation of Sazlıdere Reservoir?s trophic condition, calculated phosphorus loads arerecalculated in view of various scenarios and in what proportion these loads have to bereduced (to prevent eutrophication)Through literature survey was made about rural areas to make a stable evaluation and theseprogresses were summarized under the guideline of ` suggestions for rural areas?. Suggestedprocesses are determined with the suggested infrastructure processes and mentioned treatmentprocess choices.Related to the subject, examples of wetland studies in the foreign countriesare given. Besides economical and environmental factors that are effective to choosewastewater treatment plants summerized in these studies, low cost treatments chosen in ruralareas and wastewater management systems are also mentioned.In order to see the feasebilitiy of treatment methods mentioned above, land propertiesnecessary for treatment and sewer systems were studied in-situ and feasibility studies weremade by visiting the villages in Sazlıdere basin. The optimization studies made for together orseparate wastewater treatment, according to the results the most cost-effective treatmentmethods are determined. In the subject of separate treatment, the cost in the foreign countriesand in the inland are compared. Also, in order to be able to compare with the other treatmentmethods, built wastewater treatment plant?s flow-cost relations reflecting Turkey?s conditionon this subject were summarized by taking some data from Tuna phD studies.In the last part, the economical suitability of the concerning alternatives for transferring thewastewater are examined. Settlements in Sazlıdere basin were examined in two parts,because of geographical location, wastewater collection , and the need of central or separatetreatment. In Arnavutköy, Taşoluk and Haraçcı where large part of the population lives, nocost optimization is made by assuming that wastewater would be driven away from the basinand cost of driving the wastewater away were summarized as in the previous studies.Detailed optimization estimations were made for villages located in the North of Sazlıdere,about environmentaly friendly wastewater collection systems, best treatment technology andcost efficiency for treatment alternatives.Key Words: Sazlıdere basin water quality , pollution sources and loads, use of models for thecontrol of eutrophication, land treatment methods, wetlands, cost optimizations of wastewatertreatment