Stormwater Management Based on Resilient Urban Drainage Strategies

Source: ICHE Conference Archive - https://mdi-de.baw.de/icheArchiv

Role of Resilience in Sustainable Urban Stormwater Management

Typically, best management practices (BMPs) are implemented to help sustainable stormwater management in urban areas. Over recent decades the selection of urban stormwater management measures for a site has been a challenge among urban planners where thecriterion based on flood volume no longer suffices for selecting urban drainage solutions. Therefore there is a need to consider a set of holistic criteria beyond runoff and inundation objectives by which it would be possible to evaluate sustainability of urban drainage projects. Frequent urban flooding events have justified the use of ‘resilience’ concept and pertaining criteria.  This paper proposes a methodology to verify the sustainability of BMPs projects alongside their resilience. The multi criteria decision making (MCDM) technique has been applied for BMPs ranking based on proposed criteria. The methodology has been applied to urban drainage system of a municipal district of Tehran (Iran). Results indicate the effects of manager’s preferences on selecting BMPs. The proposed methodology provides an effective tool for urban managers to adopt more resilient-sustainable decisions in urban areas

Evaluation of Temporal and Spatial Variations of Water Quality Parameters in Zohreh River, Iran

Discriminant analysis (DA) and principal component analysis (PCA), as multivariate statistical techniques, are used to interpret large complex water quality data and assess their temporal and spatial variation in the basin of the Zohreh river. In this study, data sets of 16 water quality parameters collected from 1966 to 2013) in 4 stations (1554 observations for each parameter) were analyzed. PCA for data sets of Kheirabad, Poleflour, Chambostan and Dehmolla stations resulted in 4, 4, 4, and 3 latent factors accounting for 88.985%, 93.828%, 88.648%, and 88.68% of the total variance in water quality parameters, respectively. It is indicated that total dissolved solids (TDS), electrical conductivity (EC), chlorides (Cl−), sodium (Na), sodium absorption ratio (SAR), and %Na were responsible for water quality variations which are mainly related to natural and anthropogenic pollution sources including climate effects, gypsum, and salt crystals in the supratidal of Zohreh river delta, fault zones of Chamshir I and II, drainage of sugarcane fields, and domestic and industrial wastewaters discharge into the river. DA reduced the data set to only seven parameters (discharge, temperature, electrical conductivity, HCO3-, Cl-, %Na, and T-Hardness), affording more than 58.5% correct assignations in temporal evaluations and describing responsible parameters for large variations in the quality of the Zohreh river

نقش عوامل محیطی در انتقال ویروس SARS- CoV- 2 و راهکارهای کاهش آن

Background and Aims: Limited knowledge about SARS-CoV-2 transmission mechanism and the affecting factors is a global challenge. Due to the high prevalence of Covid-19 pandemic, airborne transmission of SARS-CoV-2 is more important than other modes of transmission. To investigate the airborne transmission of this virus, indoor air sampling was performed in COVID-19 ward of Sina Hospital in Ahvaz. Materials and Methods: Air samples were collected from two sampling points with a distance of less than or equal to 1 meter from the patient bed (in the patient's room) and more than 3 meters from the patient bed (in the corridor and the nurse station) Sampling was conducted through both active and passive methods. The collected samples were then transferred to the laboratory in the cold chain, where they were tested for the presence or absence of virus by reverse transcription polymerase chain reaction (RT-PCR). Ethical considerations were observed in all stages of the study. Results: Of the total air samples collected in our study, (21 samples), 9.52 % of the samples (2 samples) were positive for SARS-CoV-2, both of which were positive in the patient's room and were obtained by active air sampling method. Also, multivariate analysis showed that among the studied parameters, the highest correlation was found between the presence of virus in air samples and temperature, relative humidity, and concentration of particles in the air. Conclusion: The results indicate the presence of SARS-CoV-2 bioaerosols in the air inside the hospital.زمينه و اهداف: دانش محدود در مورد مکانیسم انتقال ویروس SARS-CoV-2 و عوامل تاثیر گذار بر آن یک چالش در مقیاس جهانی است. با توجه به شیوع بالای اپیدمی کووید-19، انتقال هوایی ویروس نسبت به دیگر راه‌های انتقال مورد توجه بیشتر می‌باشد. بنابراین در این مطالعه به بررسی نقش انتقال هوایی این ویروس، نمونه برداری از هوای داخلی بخش بستری بیماران کرونایی بیمارستان سینا اهواز انجام شد. مواد و روش‌ها: در هر یک از محل­های نمونه برداری، از دو نقطه با فاصله‌ی کمتر یا مساوی 1 متر از تخت بیماران (در اتاق بیماران) و فاصله بیش از 3 متر از تخت بیماران (در راهرو و ایستگاه پرستار) نمونه هوا به دو روش فعال و غیر فعال جمع آوری و در زنجیره‌ی سرما به آزمایشگاه منتقل شد. سپس با استفاده از واکنش زنجیره‌ای پلیمراز رونویسی معکوس (RT- PCR) برای حضور یا عدم حضور ویروس مورد بررسی قرار گرفتند. در تمام مراحل، ملاحظات اخلاقی مد نظر قرار گرفت.  يافته‌ها: از کل نمونه‌های هوای (21 نمونه) جمع‌آوری‌ شده برای حضور ویروس SARS-CoV-2، 52/9% نمونه‌ها (2 نمونه) مثبت شدند که هر 2 نمونه مثبت در اتاق بیماران و توسط روش نمونه­برداری فعال هوا ثبت شدند. تجزیه و تحلیل چند متغیره نشان داد که از بین پارامترهای مورد مطالعه، بیشترین همبستگی بین حضور ویروس در نمونه‌های هوا با دما، رطوبت نسبی، غلظت ذرات موجود در هوا به دست آمد. نتيجه‌گيري: تحقیق بیانگر وجود بیوآئروسل‌های SARS-CoV-2 در هوای داخل بیمارستان می‌باشد