Ayse Muhammetoglu

Implementation of Hydraulic Modelling for Water-Loss Reduction Through Pressure Management

This study was conducted in the Konyaalti Water Distribution Network in Antalya, Turkey. The study area was divided into 18 district metered areas (DMAs) for better management of water losses. Water levels in reservoirs, flow rates, and water pressures were monitored on-line by the SCADA data system. A hydraulic model was calibrated and verified for each DMA using data provided by SCADA. The model results revealed that a number of DMAs exhibited high pressures, greater than 3.5 bars, and high minimum night flow (MNF) throughout the year. Also, the Infrastructure Leakage Index (ILI) for the study area was greater than 20, indicating high water losses. As a result of these findings, a pressure reducing valve (PRV) was installed at DMA No. 2 as an example and set at 3.0 bars resulting in considerable reduction in water losses. The optimum pressure level for setting the PRV was chosen using the hydraulic model. The same model was used to predict water savings due to pressure reduction. The predicted water savings were verified using long periods of flow rates and water pressure profiles. The predicted and measured water savings showed good agreement. The study concluded that hydraulic modelling is essential for applying appropriate pressure management strategies.

A three-dimensional water quality-macrophyte interaction model for shallow lakes

A dynamic three-dimensional water quality model for macrophyte-dominated shallow lakes was proposed and tested. The proposed model is capable of simulating macrophytes and its interactions with water quality constituents such as dissolved oxygen (DO), organic nitrogen, ammonia, nitrate, organic phosphorus, orthophosphate, biochemical oxygen demand, phytoplankton and the sediment layer in shallow lakes. An existing two-dimensional hydrodynamic model has been utilized in conjunction with the water quality model to simulate water levels, velocities and flow rates. The modelled macrophyte processes are photosynthesis, respiration, mortality and excretion. Hourly simulation of photosynthesis process has been realized. The hourly simulations need special attention to predict diurnal variations of DO in macrophyte dominated lakes. The proposed water quality simulation model was subjected to calibration, verification and prediction processes using the data collected from Mogan Lake, Turkey. Mogan Lake exhibits wide variations of macrophyte biomass seasonally. The lake also exhibits highly variable DO levels both seasonally and diurnally. Statistical error quantification methods have been utilized to test the goodness of fit between the water quality model predictions and field measurements. Good agreement has been achieved between model predictions and measurements. Moreover, uncertainty analysis has been carried out for macrophyte and DO constituents. The analysis showed that the magnitude of the saturated growth rate of macrophyte is the most sensitive model parameter both for macrophyte and DO. The proposed water quality simulation model gave some promising initial results as a management tool to predict the expected reductions for the undesired consequences of eutrophication problem.

Prediction of wastewater dilution and indicator bacteria concentrations for marine outfall systems.

This paper describes a modeling study of near-field and far-field dilution of discharged effluents from a deep sea outfall system in Antalya Bay of Turkey. Initial dilution and wastewater plume behavior were simulated by Visual Plumes-UM3 model whereas Brooks dispersion model and first order bacterial decay formulations were used to simulate far-field dilution. The input data sets were collected by detailed field and lab investigations for effluent discharges (flow rate, total and fecal coliform concentration) and ambient environment (oceanographic and current measurements). Geostatistical methods and GIS were used to visualize results of the bacteriological sampling study. Site specific bacterial inactivation rates were determined by both in-situ and lab-scale experiments. Total dilution values and bacteria concentrations were predicted. Good agreement between predicted and measured total and fecal coliform concentrations were obtained for homogeneous and density stratified ambient conditions. Discussion on wastewater dilution mechanisms was presented with recommendations for similar future studies.

Evaluation of the Environmental Impact of Pesticides by Application of Three Risk Indicators

This study compares three pesticide-risk indicators: 1) the environmental impact quotient (EIQ), 2) the toxicity, human health, and persistency hazard rating system (THP), and 3) the pesticide environmental risk indicator (PERI) to evaluate the environmental impacts of active ingredients in pesticides. Environmental risk scores were obtained and evaluated for commonly used pesticides in Kumluca region of Turkey. The risk scores of EIQ and THP were in good agreement. This study provides an example applicable in other areas where environmental measurements of pesticides are either unaffordable or not physically feasible. The selected pesticide risk indicators are easily applied and helpful tools for pest management practitioners. However, site specific components (surface runoff, particle transport processes, and spatial variability of pesticide transport in soil) and exposure of consumers to pesticide residues are missing in the selected indicators. Forensic methods and approaches could be applied in conjunction with existing indicator models to better understand pesticide fate and transport and improve their selection and application pattern.

Management of chlorine dosing rates in urban water distribution networks using online continuous monitoring and modeling

The aim of this study is to present the results of a research which was undertaken to manage chlorine dosing rates in a real water distribution network using online continuous monitoring and modeling. The study area was divided into 18 district metered areas (DMAs) where the water pressure and flow rate measurements to each DMA were online and continuous. Besides, online water quality sensors were installed at eight different locations and a bimonthly water quality measurement and sampling program was carried out. The data sets required to set, calibrate and verify the hydraulic and chlorine models were derived from the online continuous monitoring and sampling program. Eight chlorine management scenarios that take into consideration the extreme conditions found out during the online monitoring and sampling were utilized. The study revealed that online monitoring provides excellent data sets for chlorine modeling and management that enables automatic application of chlorine dosing.

Full-Scale PAT Application for Energy Production and Pressure Reduction in a Water Distribution Network

AbstractPressure management is an effective method to reduce water loss. A common way to reduce pressure and water loss in water distribution networks (WDNs) is to use pressure-reducing valves (PRV...

A Fuzzy Logic Application to Environment Management System: A Case Study for Goksu Streams Water Quality Assesment

Water quality management is an important issue of relevance in the context of present times. Water quality indices are computed for classification of water wherein the integration of parametric information on water quality data and the expert’s knowledgebase on their importance & weights are considered. Considerable uncertainties are involved in the process of defining water quality for specific usage. Antalya City, located along the coasts of Mediterranean Sea in Turkey, is famous worldwide due to its tourism potential. Antalya City has a beautiful landscape composed of mountains, forests, beautiful beaches and the sea. In order to apply sustainable tourism principles in Antalya, the protection of valuable environmental resources gains a particular importance. A land survey study was carried out to determine the pollution loads of Bogacay Stream, an important land-based pollution source of Antalya City, for one year duration. According to the water quality classifications obtained from Fuzzy Logic, water quality changes temporally in Bogacay Stream and an occasional critical level of water quality was determined in July which coincides with the peak use of the beach for recreational activities. Goksu Stream is the main source of Bogacay Stream. It always carries main part of water to Bogacay. So, on a large scale Goksu Stream determines the Bogacay Stream’s water quality.

Real time monitoring and control in water distribution systems for improving operational efficiency

AbstractThe global water sector faces challenges to maintain safe, healthy, and adequate water supply to its consumers. Control of water quality and quantity by real-time monitoring (RTM) plays an important role in the management of water distribution systems (WDSs) and protection of consumers’ health. RTM could be used for monitoring and analyses of water quality parameters to ensure its suitability for drinking. Additionally, RTM system warns operators to stop water supply to save water and minimize risks when needed. WDS of Antalya City is monitored and controlled by an advanced RTM and Supervisory Control and Data Acquisition (SCADA) system. Integrated RTM–SCADA system monitors and controls both hydraulic and water quality parameters to improve the WDS’s operational efficiency. The system automatically controls pumps and valves and it has security alarms if any of the monitored water quality parameters fail to comply with the drinking water quality standards. This feature helps to protect WDS from the...

Excess Pressure in Municipal Water Supply Systems as a Renewable Energy Source: Antalya Case Study

Pressure management is one of the most effective methods for water loss reduction. Pump used in turbine mode (pump as turbine, PAT) is a viable option for reducing excess water pressure, water losses, and pipe failures in water distribution networks in addition to energy production at microscale. In this study, a PAT system recently installed in Antalya City of Turkey is presented, and its performance is evaluated for its initial operational period of approximately 5 months. This full-scale PAT system was implemented in a parallel pipeline with a pressure-reducing valve (PRV). The operation of the PAT system was continuously monitored online for flow rate, power, and pressure levels. The PAT system proved to work efficiently in a wide range of inflows (130–300 m3/h) where the produced energy varied between 0.7 and 8.4 kWh for a reduction of approximately 1 bar pressure head with an average efficiency of 60%. Environmental benefits of green energy production, reduction in physical water losses, and carbon dioxide emissions were evaluated. The payback period of the PAT application was computed as 53 days based on the costs and revenues of the PAT application.

Uncertainty and sensitivity analysis of dilution processes for marine discharges

Sea outfall systems are cost-effective solutions for final disposal of the wastewaters generated in coastal areas. Main design parameters of an outfall system are flow rate, initial bacteria concentration of the effluent, time required for 90% reduction of bacteria (T90), ambient currents, discharge depth and outfall length. Discharge depth and outfall length are certain parameters whereas the other parameters are usually uncertain due to their dynamic features. These parameters could be described using probabilistic approaches. In this study, uncertainty analysis has been carried out using Monte Carlo Simulation for Antalya Sea Outfall System to obtain probabilistic bacteria concentrations at recreational areas. Additionally, sensitivity analysis has also been performed to evaluate correlations of input parameters. The estimated total coliform concentrations were below 565 and 844 cfu/100 ml with 95% probability in winter and summer seasons respectively, with dominant currents and 2500 meters away from the diffuser. The most sensitive parameter on coliform concentration was current velocity for winter and initial coliform concentration of the effluent for summer season. The obtained results are evaluated for their compliance with the recreational water quality standards.