INVESTIGATING THE EFFECTS OF LOW IMPACT DEVELOPMENT (LID) ON SURFACE RUNOFF AND TSS IN A CALIBRATED HYDRODYNAMIC MODEL

The land development and increase in urbanization in a watershed affect water quantity and water quality. On one hand, urbanization provokes the adjustment of geomorphic structure of the streams, ultimately raises peak flow rate which causes flood; on the other hand, it diminishes water quality which results in an increase in Total Suspended Solid (TSS). Consequently, sediment accumulation in downstream of urban areas is observed which is not preferred for longer life of dams. In order to overcome the sediment accumulation problem in dams, the amount of TSS in streams and in watersheds should be taken under control. Low Impact Development (LID) is a Best Management Practice (BMP) which may be used for this purpose. It is a land planning and engineering design method which is applied in managing storm water runoff in order to reduce flooding as well as simultaneously improve water quality. LID includes techniques to predict suspended solid loads in surface runoff generated over impervious urban surfaces. In this study, the impact of LID-BMPs on surface runoff and TSS is investigated by employing a calibrated hydrodynamic model for Sazlıdere Watershed which is located in Istanbul, Turkey. For this purpose, a calibrated hydrodynamic model was developed by using Environmental Protection Agency Storm Water Management Model (EPA SWMM). For model calibration and validation, we set up a rain gauge and a flow meter into the field and obtain rainfall and flow rate data. And then, we select several LID types such as retention basins, vegetative swales and permeable pavement and we obtain their influence on peak flow rate and pollutant buildup and washoff for TSS. Consequently, we observe the possible effects of LID on surface runoff and TSS in Sazlıdere Watershed.

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Dampak Perubahan Penggunaan Lahan Terhadap Limpasan Permukaan dan Laju Aliran Puncak Sub DAS Gajahwong Hulu Kabupaten Sleman

JURNAL PEMBANGUNAN WILAYAH & KOTA ◽

10.14710/pwk.v12i2.12890 ◽

2016 ◽

Vol 11 (4) ◽

pp. 127 ◽

Cited By ~ 1

Author(s):

Andiri Rahardian ◽

Imam Buchori

Keyword(s):

Flow Rate ◽

Water Conservation ◽

Surface Runoff ◽

Open Space ◽

Peak Flow ◽

Watershed Hydrology ◽

Peak Flow Rate ◽

Landuse Change ◽

Catchment Areas ◽

The Impact

Upstream Gajahwong Sub-Watershed included in Yogyakarta Urban Agglomeration Region and regional development of tourism that utilizes the beauty of the slopes of Mount Merapi also the support accessibility (Solo-Magelang-Semarang road; this condition is assumed to be the cause of landuse changes, followed by vegetation land shrinkage. The shrinkage’s result is water catchment areas reduction that disrupts the Sub-Watershed hydrology function. One of indication is the increasing flood discharge that can be seen from the changes in surface runoff and peak flow rate. This research aims to assess the impact of landuse change on surface runoff and peak flow rate in Gajahwong Sub-Watershed using a quantitative method that consists of spatial and mathematic analysis with SCS and Rational Method. The results showed that the landuse changes impact on increasing surface runoff and peak flow rate. The surface runoff in year 2002 amounted to 3.073 mm with a peak flow rate of 98.02 m³/sec then increased to 3.901 mm with a peak flow rate of 101.65 m³/sec in year 2011. The landuse changes that occur tend to built landuse which was followed by vegetation shrinkage and impact on the increase in surface runoff and peak flow rate. Predictions in year 2031 also showed an increase in surface runoff and peak flow rate, if there is a tendency of landuse changes linearly as landuse changes in year 2002 – 2011. Alternative analytical efforts to handle surface runoff and peak flow rate showed that by combining the development of Green Open Space with water conservation technology (Biopori and Infiltration Wells) can reduce surface runoff and peak flow rate.

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Correlation of intravesical prostatic protrusion with severity of lower urinary symptoms among patients with benign prostatic hyperplasia

African Journal of Urology ◽

10.1186/s12301-020-00102-0 ◽

2021 ◽

Vol 27 (1) ◽

Author(s):

Babatunde K. Hamza ◽

Muhammed Ahmed ◽

Ahmad Bello ◽

Musliu Adetola Tolani ◽

Mudi Awaisu ◽

...

Keyword(s):

Flow Rate ◽

Bladder Outlet Obstruction ◽

Peak Flow ◽

Prostate Volume ◽

Outlet Obstruction ◽

Peak Flow Rate ◽

The Mean ◽

Benign Prostate ◽

Intravesical Prostatic Protrusion ◽

Lower Urinary

Abstract Background Benign prostate hyperplasia (BPH) is characterized by an increase in the number of epithelial and stromal cells in the periurethral area of the prostate. Lower urinary tract symptoms (LUTS) often develop as a manifestation of bladder outlet obstruction (BOO) due to benign prostate enlargement. When the prostate enlarges, protrusion into the bladder often occurs as a result of morphological changes of the gland. Prostatic protrusion into the bladder can be measured with ultrasound as intravesical prostatic protrusion (IPP). There are studies that have shown IPP as a reliable predictor of bladder obstruction index (BOOI) as measured by pressure flow studies. IPP is thereby reliable in assessing the severity of BOO in patients with BPH. The severity of symptoms in patients with BPH can be assessed through several scoring systems. The most widely used symptoms scoring system is the International Prostate Symptoms Score (IPSS). The aim of this study is to determine the correlation of IPP with IPSS in men with BPH at our facility. Methods The study was a cross-sectional observational study that was conducted at the Division of Urology, Department of Surgery, in our facility. The study was conducted on patients greater than 50 years LUTS and an enlarged prostate on digital rectal examination and/or ultrasound. All consenting patients were assessed with the International Prostate Symptoms Score (IPSS) questionnaire, following which an abdominal ultrasound was done to measure the intravesical prostatic protrusion (IPP), prostate volume (PV) and post-void residual (PVR) urine. All the patients had uroflowmetry, and the peak flow rate was determined. The data obtained were entered into a proforma. The results were analyzed using Statistical Package for Social Sciences (SPSS) software package version 20. Results A total of 167 patients were seen during the study period. The mean age was 63.7 ± 8.9 years, with a range of 45–90 years. The mean IPSS was 18.24 ± 6.93, with a range of 5–35. There were severe symptoms in 49.1%, while 43.1% had moderate symptoms and 7.8% had mild symptoms. The overall mean IPP was 10.3 ± 8 mm. Sixty-two patients (37.1%) had grade I IPP, 21 patients (12.6%) had grade II IPP and 84 patients (50.3%) had grade III IPP. The mean prostate volume and peak flow rate were 64 g ± 34.7 and 11.6 ml/s ± 5.4, respectively. The median PVR was 45 ml with a range of 0–400 ml. There was a significant positive correlation between the IPP and IPSS (P = 0.001). IPP also had a significant positive correlation with prostate volume and post-void residual and a significant negative correlation with the peak flow rate (P < 0.01). Conclusion Intravesical prostatic protrusion is a reliable predictor of severity of LUTS as measured by IPSS, and it also shows good correlation with other surrogates of bladder outlet obstruction.

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Decreasing peak flow rate with a new bag-valve-mask device: effects on respiratory mechanics, and gas distribution in a bench model of an unprotected airway

Resuscitation ◽

10.1016/s0300-9572(03)00032-7 ◽

2003 ◽

Vol 57 (2) ◽

pp. 193-199 ◽

Cited By ~ 16

Author(s):

Horst G. Wagner-Berger ◽

Volker Wenzel ◽

Angelika Stallinger ◽

Wolfgang G. Voelckel ◽

Klaus Rheinberger ◽

...

Keyword(s):

Flow Rate ◽

Respiratory Mechanics ◽

Peak Flow ◽

Peak Flow Rate ◽

Gas Distribution ◽

Unprotected Airway ◽

Bench Model

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Development of an empirical formula for estimation of bioretention outflow rate

Water SA ◽

10.4314/wsa.v45i2.07 ◽

2019 ◽

Vol 45 (2 April) ◽

Cited By ~ 1

Author(s):

Sezar Gulbaz ◽

Cevza Melek Kazezyılmaz-Alhan ◽

Rasim Temür

Keyword(s):

Empirical Formula ◽

Peak Flow ◽

Groundwater Resources ◽

Low Impact Development ◽

Initial Moisture Content ◽

Peak Flow Rate ◽

Impervious Area ◽

Outflow Rate ◽

Cent Error ◽

Peak Value

Urbanization of a watershed affects both surface water and groundwater resources. When impervious area increases, the excess runoff and volume of water collected at the downstream end of the watershed also increases, due to the decrease in groundwater recharge, depression storage, infiltration and evapotranspiration. Low-impact development (LID) methods have been developed in order to diminish adverse effects of excess stormwater runoff. Bioretention is one of the LID types which is used to prevent flooding by decreasing runoff volume and peak flow rate, and to manage storm-water by improving water quality. In this study, an empirical formula is derived to predict the peak outflow out of a bioretention column as a function of the ponding depth on bioretention, hydraulic conductivity, porosity, suction head, initial moisture content and height of the soil mixture used in the bioretention column. Coefficients of the empirical formula are determined by using metaheuristic algorithms. For analyses, the experimental data obtained from rainfall-watershed-bioretention (RWB) system are used. The reliability of the empirical formula is evaluated by calculating the absolute per cent error between the peak value ofthe measured outflow and the calculated outflow of the bioretention columns. The results show that the performance of the empirical formula is satisfactory.

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Diminished long-term recovery of peak flow rate (PFR) after robotic prostatectomy in men with baseline PFR <10 mL/s and incidental association with high-risk prostate cancer

LUTS Lower Urinary Tract Symptoms ◽

10.1111/luts.12199 ◽

2017 ◽

Vol 11 (1) ◽

pp. 78-84

Author(s):

Adam Gordon ◽

Douglas Skarecky ◽

Kara N. Babaian ◽

Harleen Dhaliwal ◽

Thomas E. Ahlering

Keyword(s):

Prostate Cancer ◽

High Risk ◽

Flow Rate ◽

Peak Flow ◽

Robotic Prostatectomy ◽

Peak Flow Rate ◽

High Risk Prostate Cancer ◽

Risk Prostate Cancer

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A Method of Measuring the Peak Flow-Rate and the Regurgitant Volume of Regurgitation

Biofluid Mechanics ◽

10.1007/978-3-642-52338-0_15 ◽

1990 ◽

pp. 125-129

Author(s):

Motoaki Sugawara ◽

Akio Hirai ◽

Yasutsugu Seo ◽

Yasuo Miyajima ◽

Takanobu Uchibori

Keyword(s):

Flow Rate ◽

Peak Flow ◽

Peak Flow Rate ◽

Regurgitant Volume

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Evaluating the Impacts of Integrated Pollution on Water Quality of the Trans-Boundary Neris (Viliya) River

Sustainability ◽

10.3390/su10114239 ◽

2018 ◽

Vol 10 (11) ◽

pp. 4239 ◽

Cited By ~ 7

Author(s):

Marina Valentukevičienė ◽

Lina Bagdžiūnaitė-Litvinaitienė ◽

Viktoras Chadyšas ◽

Andrius Litvinaitis

Keyword(s):

Water Quality ◽

Water Treatment ◽

Technological Development ◽

Treatment Plant ◽

Water Treatment Plant ◽

Suspended Solid ◽

Storm Water ◽

Boundary Area ◽

Water Flows

The trans-boundary area between the Europe Union and other countries is highly susceptible to changes in water quality and variations in the potential pollution load that could influence its eco-systems significantly. The Neris (Viliya) River is one of the biggest surface water bodies in Lithuania and Belarus with an ecologically important area protected by international legislation. The study was aimed at evaluating the impacts of integrated pollution on water quality of the Neris River taking into account different storm-water flows and ecological scenarios. For this purpose, qualitative and quantitative statistical evaluation was set up and calculation was done; different integrated pollution loads of the catchment area were estimated. The evaluation considered a decrease in river discharge due to changes in the regional storm-water flow and technological development that should lead to the growing covered surface and a reduction in the untreated storm-water flows. The obtained results indicated that, in the case of storm-water treatment, the total nitrate and phosphate concentrations will decrease, while in the cases of changes in combined suspended solid, the concentration of nutrients will decrease. Thus, a trans-boundary storm-water treatment plant of the Viliya River is required as it should eliminate pollution accumulation and restore its acceptable environmental status. A coordinated international project for the entire catchment of the Neris (Viliya) River based on the specifications and requirements of the EU Water Framework Directive (EU 2000) should be developed and implemented. Subsequently, ecological river-use policies should be established at the international level, which should offer considerable perspectives for the sustainable development of the area.

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