Peyzaj sulamasında kullanılan alternatif su kaynakları: Beylikdüzü, Saklıhan konakları örneği
Alternative water resources for landscape irrigation systems: The example of Beylikduzu Saklıhan konakları
Yazar: BEGÜM ALTINDENİZ
Danışman: DOÇ. DR. YASİN ÇAĞATAY SEÇKİN
İstanbul Teknik Üniversitesi / Fen Bilimleri Enstitüsü / Peyzaj Mimarlığı Ana Bilim Dalı
Derece: Yüksek Lisans, 2012
Konu: Peyzaj Mimarlığı = Landscape Architecture
Dizin: Basınçlı sulama sistemleri = Pressure irrigation systems ; Damla sulama sistemi = Drip irrigation system ; Sulama = Irrigation ; Sulama suyu miktarı = Irrigation quantity ; Yağmur suyu = Rain water

Özet:
Su, tüm canlıların yaşamsal fonksiyonlarını devam ettirebilmeleri için gerekli olan doğal bir kaynaktır. Kullanılabilir su miktarının, yeryüzünde dağılımı düzensizdir. Artan insan nüfusu, küresel ısınma, kuraklık, bilinçsiz su tüketim politikaları ve benzeri nedenler, mevcut tatlı su kaynaklarının azalmasına neden olmuştur. Bu noktada alternatif su kaynaklarına verilen önem artmış ve bu konuda yapılan çalışmalar hız kazanmıştır. Sulama, bitkinin gelişmesi için gerekli olan ancak doğal yağışlarla karşılanamayan suyun toprağa verilmesi biçiminde tanımlanır. Sulama sistemi, sulama yapılacak alanın doğal verileri olan; iklim, toprak özellikleri, mikroklima ve alandaki bitkisel dokuya uygun olarak planlanır. Bu veriler doğrultusunda yağmurlama ve /veya damlama sulama sistemleri ile sulanır.Sulama suyu, günlük su tüketiminin önemli bir yüzdesini oluşturmaktadır. Türkiye'de suyun sektörel kullanımında, sulama amaçlı kullanım %77'dir. Sulama suyu böylesine yüksek bir orana sahip iken, sulama sistemi projesini doğru planlamak ve alternatif su kaynaklarına yönelmek doğru olacaktır. Tez kapsamında, yukarıda yer alan verilerden yola çıkılarak, sulama sistemlerinde kullanılabilecek alternatif su kaynakları 'peyzaj sulaması' başlığı altında incelenmiştir. Bina ölçeğinde kolaylıkla uygulanabilen yağmur suyu depolama yöntemi ve gri suyun arıtılması yöntemi alternatif su kaynağı olarak seçilmiştir. Seçilen bu kaynaklar; sistem kurulumu, maliyet ve bakım başlıkları altında incelenerek, projeye uygunlukları tartışılmış, avantajları ve dezavantajları ortaya konmuştur. Çıkan sonuçlar doğrultusunda hangi kaynağın proje uygun ve sürdürülebilir olduğuna karar verilmiştir. Seçilen proje alanı, İstanbul, Beylikdüzü ilçesinde yer alan Saklıhan Konakları sitesidir. Saklıhan Konakları peyzaj sulama projesi, seçilen iki alternatif su kaynağı olan yağmur sularının depolanması ve gri suyun arıtılması yönünden incelenmiştir. Öncelikle alternatif su kaynakları miktar olarak analiz edilerek, sulama suyu ihtiyacının ne kadarını karşılayabildikleri ortaya konmuştur. Daha sonra, sistem bileşenleri, maliyet ve bakım başlıkları altında değerlendirilmişlerdir. Elde edilen sonuçlar doğrultusunda, yağmur suyunun depolanmasının, sistemin kurak mevsim boyunca ihtiyaç duyduğu sulama suyunu karşılayamadığı, ancak kurakçıl peyzaja uygun bitkilendirme düzenlemeleri, yağmur bahçeleri gibi kullanımlarla birlikte tasarlanarak etkin ve ucuz maliyetli bir alternatif su kaynağı olabileceği sonucuna varılmıştır. Arıtılmış gri su ise, miktar olarak ihtiyaç duyulan suyun çok üstünde çıkmıştır. Bu nedenle gri suyun %40-50'sini oluşturan az kirli suyun arıtılmasının, hem sistem kurulum maliyeti olarak, hem de enerji tüketimi açısından daha uygun bir kaynak olduğuna ve etkin biçimde uzun yıllar boyunca kullanılabileceği sonucuna ulaşılmıştır.

Abstract:
Water is a natural resource that is required to keep the vital functions of people and all living things. Water in nature has a variety of types. The distribution of useful water on the earth is irregular. The increasing human population, global warming, drought and unconscious water consumption policies has led to reduction of available fresh water resources. At this point, increased attention to alternative water resources and studies on this issue has gained momentum.Irrigation covers a high percentage of daily water usage. In Turkey the percentage of the irrigation water in sectoral usage is 77 %. Even irrigation water has a higher rate, irrigation system projects should be very well planned and to be heading for usage of alternative water resources.In this study, according the data as bellows; alternative water supplies that can be used in irrigation systems were examined under the topic "landscape irrigation". In terms of this, we prefer that, rainwater harvesting and recycling grey water supplies methods are much useful and easily applicable for the building scale. The objective was to point out the economic and the ecologic advantages and disadvantages of these alternative water supplies in contrast to municipal water. Irrigation is an artificial application of water to the soil through various systems of tubes, pumps, and sprays. Irrigation is normally used in areas where rainfall is inconsistent or dry conditions or drought is expected. There are different types of irrigation systems, depending on how the water is spread throughout the field. Some general types of irrigation systems are, sprinkler irrigation systems and drip irrigation systems. In sprinkler irrigation water is applied to all field by means of rotating sprinklers or mini-sprinklers connected to a pressurized pipe system. Sprinkler spread water over a radius of 5 to 300 feet as depending on design. This type of system is commonly used in lawns, golf courses, cemeteries, parks, and other turf areas. Drip irrigation, also known as trickle irrigation or micro irrigation or localized irrigation, is an irrigation method that saves water and fertilizer by allowing water to drip slowly to the roots of plants, either onto the soil surface or directly onto the root zone, through a network of valves, pipes, tubing, and emitters. It is done through narrow tubes that deliver water directly to the base of the plant. This type of system is commonly use in flowerbeds, shrub areas. These irrigation systems are chosen through the natural factors of the irrigation area. The main natural factors are climate, soil type, plantation and microclimate. Climate includes rainfall, air movements, damp, temperature and wind. The number of rainy days and amount of rain water in dry season determine the amount ofirrigation water and the days, that needed irrigation.Soil is a natural body consisting of layers (soil horizons) that are primarily composed of minerals which differ from their parent materials in their texture, structure, xixconsistency, color, chemical, biological and other characteristics. The most important soil property is infiltration rate. Infiltration is the process by which water on the ground surface enters the soil. Infiltration rate in soil science is a measure of the rate at which soil is able to absorb rainfall or irrigation. It is measured in inches per hour or millimeters per hour. The rate decreases as the soil becomes saturated. If the precipitation rate exceeds the infiltration rate, runoff will usually occur unless there is some physical barrier. It is related to the saturated hydraulic conductivity of the near-surface soil. The rate of infiltration can be measured using an infiltrometer. Infiltration depends soil types. There is three types of soil. These are sandy soils, sandy and clayey soil and clayey soil. Plantation is another important factor of the choice of irrigation system type. Plants are divided into three groups according to the water necessity. These are droughtresistant plants, drought-tolerant plants, drought-susceptible plants. Landscape designers have to design plantation projects to explore an encourage the use of more sustainable irrigation technologies.A microclimate is a local atmospheric zone where the climate differs from the surrounding area. The term may refer to areas as small as a few square feet or as large as many square miles. Microclimates exist, for example, near bodies of water which may cool the local atmosphere, or in heavily urban areas where brick, concrete, and asphalt absorb the suns energy, heat up, and reradiate that heat to the ambient air: the resulting urban heat island is a kind of microclimate. The selected project area, named Saklihan Mansions, is located in Beylikdüzü, Istanbul. The irrigation system of the project is planned with rainwater harvesting and grey water treatment methods. Rainwater harvesting is the practice of capturing and storing rain to provide water for human use. Rainwater harvesting systems most frequently collect water from building roofs and store it in tanks, called cisterns. The system components are; surfaces of capturing rain water (roofs), horizontal and vertical gutters, filters, cisterns, piping.Grey water refers to the reuse of water drained from baths, showers, washing machines, and skins (household wastewater excluding toilets wastes) for irrigation and other water conservation applications. Grey water consists 50%-80% of domestic waste water. Less dirty grey water consists 40-50% of grey water. In recent years most popular and effective grey water treatment system is Membran Bioreactor, which provides clean water for sprinkler irrigation systems. At this thesis this treatment method is chose. Membrane bioreactor (MBR) is the combination of a membrane process like microfiltration or ultrafiltration with a suspended growth bioreactor, and is now widely used for municipal and industrial wastewater treatment. The system components are; interior and exterior piping, pre-storage tank, MBR Tank and clean water tank.The selected project area, named as Saklihan Mansions, is located in Beylikdüzü, Istanbul. The irrigation system of the project is planned with rainwater harvesting and grey water treatment methods. Firstly we analyze how much of these alternative water sources could meet need of irrigation water. Later on evaluate these sources xxunder three main topics, which are system components, cost of installation and maintenance of these systems. Through the calculations, we reach these data. Total green area of Saklihan Mansions is 5.025 m2. Landscape is needed 124 days irrigation in dry season. Daily water demand for irrigation is 33,98 m3. Rainwater harvesting system will collect averagely 780,912 m3water in dry season. Grey water treatment system provides 159,20 m3daily clean water. Less dirty grey water provides 79,60 m3daily clean water.As a result of these water amounts, rainwater harvesting system could not meet the need of irrigation water during the dry season, but appropriate planting water-wise landscaping arrangements, such as rain gardens, designed places uses with this system, could create a cost-effective and cheap alternative water source.On the other hand, grey water treatment methods were much higher than the amount of water needed. Because of these, %40-50 of refined less dirty water, could be sufficient and even better for the installation cost of the system, as well as a source of energy consumption and can be used effectively for many years has been concluded.Alternative water resources was evaluated irrigation system in terms of the additional system components and costs. The cost of irrigation system is $22.356,38. The additional cost of less dirty grey water treatment system is $180.497,00. The additional cost of rain water harvesting system is $1.7240,00.The system components and cost issues are examined and the following conclusions were reached;At this stage, the amount of rainwater storage that can not be enough and the system due to the additional costs for this project was decided that, it is not a suitable or useful alternative water source.Refined less dirty gray water usage in irrigation system and system installation's additional cost is $180,497.00. However , if only tap water source was used for the project, it would brings the additional cost of $12,648.00 per year. When we are evaluated these two data, less dirty grey water system going to come its break even point cost after 16 years. However ,stored refined gray water in the irrigation water is approximately more than 2 or 3 times. These oversupply of refined less dirty gray water could be used safely for interior exterior cleaning of buildings, cleaning of common areas on the site, cleaning of toilets reservoirs and could used for the washing machines. With This usage , tap water using will decrease and as a result of this, occupants of an apartment will spent less money. Economically, Investment for the gray water system's accounting rate of return comes to break even point earlier and it brings economic advantages to occupants.When we evaluate grey water treatment on the ecological side. Only with the irrigation of landscape, we will save 4.214 m3 water per year and 40% of Grey water is kept from mixing to sewage.