Measurement and simulation of dissolved oxygen in Zayandehrood river

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1 [Downloaded free from ttp:// on Wednesday, November 06, 2013, IP: ] Click ere to download free Android application for tis jour original article Measurement and simulation of dissolved oxygen in Zayanderood river Amad Reza Rasepar, Medi Kiadani (Hajian) 1,2, Moammad Medi Amin 2 Darab Healt Center, Fars, Iran, and Department of Environmental Healt Engineering, Isfaan University of Medical Sciences, Isfaan, Iran 1 Scool of Engineering, Edit Cowan University, WA 6027, Australia, 2 Environment Researc Center, Isfaan University of Medical Sciences, Isfaan, Iran Address for correspondence: Dr. Medi Kiadani (Hajian), Isfaan University of Medical Sciences, Hezar Jerib Avenue, Isfaan, Iran. m.kiadani@ecu.edu.au ABSTRACT Aims: Tis study aims to simulate dissolved oxygen of Zayanderood river from regulating dam to PolleKalle bridge using MIKE11 software tat is a ydrodynamics and water quality model. Materials and Metods: During 5 monts te samples were taken from four ydrometric stations and water quality parameters suc as dissolved oxygen, ph, BOD (1 day, 3 days, 5 days, and 7 days), NH 4, NO 3 pospate (PO 4 3 ), and temperature were measured. Morpological and ydrological data were provided and introduced into te model. Te model was calibrated and its accuracy was investigated. Results: Te results indicated tat concentration of PO 4 3, BOD 5, COD, NH 4, and NO 3 exceeded surface water standards from regulating dam to PoleKalle bridge. Te results of te prediction for te next 25 years indicated tat due to growt of population and industries along te river, concentration of some pollutants will be increased. Conclusions: Te results indicated tat altoug te current DO level is suitable for aquatic environment, tis is not adequate for fis reproduction and migration. Prediction of te river water quality parameters for te future conditions sowed tat discarge of urban and rural wastewater to river sould be avoided. In situations were release of effluent into te river is inevitable, nitrification process sould be added to wastewater treatment processes. Key words: Dissolved oxygen, MIKE11, Zayanderood river uick Response Code: INTRODUCTION In recent decades, qualititative and quantitative simulation of water resources as been developed to manage water resources and assess te effects of discarging wastewater effluent Access tis article online Website: DOI: / into receiving waters. Many matematical and numerical equations ave been used wic leads to improvement of simulation of water resources. [1,2] Computer models tat ave been used to simulate water quality are a combination of te equations tat are sitting well beside eac oter to assess te system beavior clearly and predict te system future in a simple way. [1] ualitative models of water resources are capable to assess te water quality beavior of various sources ranging from simple pollutants to more toxic pollutants bot as one or multidimensional flows. [3] In modeling water quality in rivers, te main aim is to determine te relation between ydraulic, cemical, and biological caracteristics of river system. Copyrigt: 2012 Rasepar AR. Tis is an openaccess article distributed under te terms of te Creative Commons Attribution License, wic permits unrestricted use, distribution, and reproduction in any medium, provided te original autor and source are credited. Tis article may be cited as: Rasepar AR, Kiadani (Hajian) M, Amin MM. Measurement and simulation of dissolved oxygen in Zayanderood river. Int J Env Healt Eng 2012;1:41. 1

2 [Downloaded free from ttp:// on Wednesday, November 06, 2013, IP: ] Click ere to download free Android application for tis journ Rasepar, et al.: Simulation of DO in Zayanderood river Simulation of dissolved oxygen in a river system is important. Various processes tat affect dissolved oxygen simulation include dispersion, solar radiation, saturation of dissolved oxygen, biocemical oxygen demand of carbon materials, nitrogenous oxygen demand, te effect of pospor compounds, potosyntesis, respiration, and reaeration. Various computer models are available for qualitative and quantitative simulation of water resources. Eac of tese models as special capability tat depending upon te existing demands and facilities, a suitable model is selected. [4] Tis study aims to simulate dissolved oxygen in Zayanderood river (from regulating dam to Pole Kalle bridge using MIKE11 a onedimensional computer model. In tis study, te study area te main branc of Zayanderood is located between longitude of 50, 3 to 50, 37 and latitude of 32, 17 to 32, 43. Great part of tis basin is covered by rocky mountains. [5] Zayanderood river water is a source of water for agriculture, industry, municipal (drinking), recreational, and recarging groundwater. In tis study, te upstream part of te Zayanderood river, te distance between regulating dam to Kalle Bridge tat is about 120 km, was investigated [Figure 1]. Near PoleKalle bridge about 10 m 3 /s of flowing water is diverted to Isfaan water treatment plant. MATERIALS AND METHODS MIKE 11 model is a dynamic, onedimensional modeling tool for te design, management, and operation of complex river systems. Tis software as four editors including simulation, river network, cross sections, and boundary conditions and various modules including ydrodynamic (HD), te advection dispersion, water quality (W), runoff and rainfall, sediment transfer, and flood forecasting. [6] Flow equations in ydrodynamic module of MIKE11 are continuity and momentum equations. Tese are written as follows [6] : + A x t = q (1) ( / A) + x 2 + ga A x x + g = C 2 0 AR (2) were is discarge, A is te crosssectional area, q is lateral inflow, C is Cezy rougness coefficient, R is ydraulic radius, and UOTE a is momentum correction coefficient. Based on differential equations and finite difference metod, flow dept (points) and flow discarge (points) at nodes are calculated [Figure 2]. Te advection dispersion equation in MIKE11 model is as follows. Tis equation considers two transport mecanisms of advective and dispersive transports. [6] AC + C + = + C x x AD C AKC C 2 q (3) x were C is te concentration, D is te dispersion coefficient, A is te crosssectional area, K is te linear decay coefficient, C 2 is te source/sink concentration, q is te lateral inflow discarge, x is te space coordinate, and t is te time coordinate. Te matematical equations used in water quality module of MIKE11 software use specific forms for simulation of water quality in rivers. Tese include te investigation of bacteria in sewage effluent and oter sources of pollutants in water resources; bacteria survival under te influence of different environmental conditions; canges of dissolved oxygen tat is affected by organic matter, ammonia, and oter oxygen demand substances; dispersion, degradation, and internal reactions between nutrient materials suc as ammonia, nitrite, nitrate, and pospate; evaluation of eutropication in water resources as a result of different levels of nutrient materials; cloropyll a and cemical degradation of substances; and te assessment of teir effects for different concentrations. [6] Based on mass balance, te model assesses canges in dissolved oxygen at four different levels. Te first assessment level is simple definition of oxygen; second level assessment is sligtly developed and BOD degradation as solute, suspended, and sediment or one of tem is considered; tird level of assessment considers oxygen and nutrient processes (BOD degradation as solute, suspended and sediment or one of tese processes wit nitrification); and fourt level assessment considers oxygen, nutrients, and cloropyll Zayanderood Dam Regulating Dam Camaseman PoleKalle Bridge Isfaan Hydrometric Station Evaporation Pan Rainfall Station Town & Village Stream Brances Main Stream Catcment Boundary SubCatcment Boundary Lake & Wetland Zamankan Bridge Camaseman Lenj Figure 1: Te study area Figure 2: Scematic nodding of points and points for a river section in MIKE11 model [7] 2

3 [Downloaded free from ttp:// on Wednesday, November 06, 2013, IP: ] Click ere to download free Android application for tis jour Rasepar, et al.: Simulation of DO in Zayanderood river processes togeter wit nitrification. For eac of tese elements, te related matematical relations including reaeration, nitrification, potosyntesis, respiration, BOD degradation, required oxygen for sediment, potential of limitation of nutrients in potosyntesis, and oxygen saturation ave been used in te model. A MIKE 11 model of Zayanderood was prepared by introducing 302 sections to te model. Outflow from regulating dam was introduced as te upstream boundary and stage discarge curve of ydrometric station at PoleKalle bridge was introduced as te downstream boundary. Te model was ydraulically calibrated based on te measured water levels by adjusting rougness coefficient at some cross sections. Te model was also calibrated against BOD concentration (1 day, 3 days, 5 days, and 7 days), ammonium, nitrate, pospate, and dissolved oxygen measured along Zayanderood river at regulating dam, Zamankan bridge, Camaseman, and PoleKalle bridge. Te model parameters were adjusted suc tat te results of model prediction were compatible well wit te measured values. A sensitivity analysis on te model results was carried on and te predicted values were compared wit te measured values at two middle stations. Since Zayanderood river is a narrow and low dept river, samples can be taken by and. [7] Te samples were taken from December 2007 to April 2008 on a montly basis. Pysicocemical indicators including temperature, electrical conductivity, dissolved oxygen, nitrate, pospate, ph, NH 4, and biocemical oxygen (1 day, 3 days, 5 days, and 7 days) were measured to determine K BOD coefficient. In tis study, dissolved oxygen was measured at site using DO meter (YSI55). BOD measurement was performed in accordance wit standard metod for examining water and wastewater. Dissolved oxygen was measured using bot Winkler metod and portable DO meter and similar results were obtained. [8] PH was measured at sampling site by portable d evice. Pospate, NH 4, and NO 3 were measured using DR5000 (HACH Company). All metods used to measure water quality parameters in tis study were conformed to USEPA and were in accordance wit standard metod. Electrical conductivity and temperature were measured using Hac Model conductivity meter at site. Te flow discarge was estimated from te measured water dept and from stage discarge curves available at ydrometry stations. Te coefficients of nitrification (1.088), nitrification reaction rate (0.1), reaeration coefficient (1.08), and respiration temperature ratio (1.06) were determined from model calibration. [9] To determine organic matter degradation velocity (K BOD ), BOD values of first, tird, fift, and sevent days were measured and estimated by Tomas grapical metod. Ten, final BOD was determined for eac station and was introduced to te model. Te population growt of villages along Zayanderood river was estimated for te next 25 years. Two different scenarios were considered to assess te future conditions of te river. In te first scenario, it was assumed tat 50,000 people will be added to te current population of villages surrounding Zayanderood river and as a consequence runoff and wastewater was estimated. In te second scenario, it was assumed tat wastewater produced by Saman city and te villages were collected and transferred to a wastewater treatment plant and treated before released to river in a concentrated form. Te base information for bot scenarios was introduced to te model, and te future water quality conditions of te river were predicted. RESULTS During te period of sampling in Zayanderood river, flow discarge at regulating dam increased from 14.4 m 3 /s in Marc to m 3 /s in April. Te water temperature in February at regulating dam was lowest (3 o C) and was te igest in Marc at Camaseman dam (14.1 C). Concentration of dissolved oxygen at PoleKalle bridge in December was 7.5 mg/l. Wile, at Camaseman Dam and ZamanKan bridge te igest value occurred in January as 10.2 mg/l. Te lowest concentration for ammonium occurred at Pole Kalle bridge in December was 0.04 mg/l and te igest value was recorded in Marc at regulating dam as 0.35 mg/l. Te lowest BOD 5 concentration was dedicated to December at regulating dam as 2.2 mg/l and te igest value was dedicated to PoleKalle bridge as 8.8 mg/l. DISCUSSION Te variation of dissolved oxygen along te river is sown in Figure 3. Te correlation coefficient of simulated and measured dissolved oxygen was At Camaseman dam, tis coefficient was Te dissolved oxygen of Zayanderood river sows tat due to pollutants entering te river, dissolved oxygen as dropped to below 8.5 mg/l. Tis can endanger migration and spawning fres and cold water species. Tis amount of dissolved oxygen is adequate to maintain te life of aquatic species. Concentration of BOD 5 in all stations in Marc was more tan oter monts. Tis was also proved by analysis of variance and Duncan test (P value = 000). Te experimental results sowed tat in February and Marc, BOD 5 was more tan 5 mg/l. In tis regard, te pollution level of water in Zayanderood river along te lengt considered in tis study can be considered as average. Te correlation coefficient between model and field measurement for ammonium, BOD, and nitrate at Zamankan station and Camaseman stations were more tan 0.9. Analysis of variance sowed tat tere is significant difference in average of ammonium for at least 2 monts over te period tat measurements was conducted (P value < 0.001). Duncan test sowed tat average of ammonium in Marc was different compared to oter monts. Ammonium level downstream of regulating dam indicated tat polluted water enter te river from te upstream sections. Pospate concentration in 3

4 [Downloaded free from ttp:// on Wednesday, November 06, 2013, IP: ] Click ere to download free Android application for tis journ Rasepar, et al.: Simulation of DO in Zayanderood river Figure 3: Dissolved oxygen canges along Zayanderood river from regulating dam to PoleKalle bridge in December 2008 (model results) Figure 5: Ammonia nitrogen in Marc 2008 and prediction in : (1) Pollutant increase as nonpoint source. 2033: (2) Include release of wastewater effluent from Saman wastewater treatment plant and te related villages starting from 35 km) terms of pospor ratio in unpolluted rivers as been reported to be 0.01 mg/l (0.03 mg/l based on pospate). [10] In Zayanderood river from regulating dam to PoleKalle bridge, pospate concentration exceeded 0.2 mg/l in most cases and tis indicates tat te river is polluted. Pospate wit tis level of concentration can disturb cemical coagulation of turbidity in water treatment plant. [11] Figures 4 to 6 sow te current and future conditions of te river for bot scenarios. Figure 4 sows tat for bot scenarios dissolved oxygen are decreasing toward te downstream direction; owever, te impact of second scenarios is more pronounced. In first scenario as indicated in Figure 5, ammonium canged sligtly but wen it was assumed tat wastewater enter te river at 35 km speed, ammonium concentration increased assuming tat te ypotetical wastewater treatment plant does not ave nitrification process unit. Te modeling results indicate tat selfpurification process in te river for ammonium was slow. Tis is an alarming situation and suggesting tat construction of any wastewater treatment plant along te river tat may discarge effluent into te river sould include nitrification unit as part of its design. As indicated in Figure 6, BOD variation was te same in all scenarios and tis level of BOD Figure 4: Dissolved oxygen concentration in Marc 2008 and prediction in : (1) Pollutant increase as nonpoint source. 2033: (2) Include release of wastewater effluent from Saman wastewater treatment plant and te related villages starting from 35 km) Figure 6: BOD concentration in Marc 2008 and prediction in : (1) Pollutant increase as nonpoint source. 2033: (2) Include release of wastewater effluent from Saman wastewater treatment plant and te related villages starting from 35 km) would be sufficient to classify Zayanderood river as polluted river. Zayanderood river may be a treat to Isfaan drinking water as Isfaan water treatment plant may not be able to fulfill treatment process. Using a robust model suc as MIKE 11 to predict te future condition of Zayanderood river tat is endangered by various industries and developments, and some oter activities suc as aqua culture, etc., is important. Te results of te model suggested tat release te wastewater from urban and rural treatment plants into te river sould be avoided. In situation tat tis is not avoidable, nitrification process sould be added to wastewater treatment processes. ACKNOWLEDGEMENTS Tis article is te result of MSc approved tesis, Researc Project , in Isfaan University of Medical Sciences (IUMS).Te autors would like to tank te Department of Environmental Healt Engineering and Environment Researc Center, IUMS. 4

5 [Downloaded free from ttp:// on Wednesday, November 06, 2013, IP: ] Click ere to download free Android application for tis journ Rasepar, et al.: Simulation of DO in Zayanderood river REFERENCES 1. James A. An introduction to water quality modeling. 2t ed. United States: Jon Wiley & Sons; McCutceon SC. Water quality modeling: River transport and surface excange, Vol1.: Lewis Publisers; Hosseini AH. Zayanderood a limited source in Isfaan region. Journal of Water & Wastewater 1990;3(4) [In Persian]. 4. Rauc W, Henze M, Koncsos L, Reicert P, Sanaan P, Somlyody L, Vanrollegem P. River water quality modeling. Water Sci Tecnol 1998;38: Isfaan Water Autority. Water transfer to Iran central platue DHI Software. MIKE 11 Referenc Manual Eaton AD, Franson MAH. Standard metods for te examination of water and wastewater. Wasington, DC: USA. American Public Healt Association; Viessman W Jr, Hammer MJ. Water supply and pollution control. 5t ed. New York: Harper Collins College Publisers; Jorgensen SE. Handbook of environmental data and ecological parameters. Sydney: Permanon Press; Campman D. Water quality assessment. E&FN Spon, Taylor & Francis Group; Peavy HS, Rowe DR, Tcobanoglous G. Environmental engineering. New York: McGrawHill; Source of Support: Isfaan University of Medical Sciences, Conflict of Interest: None declared. (Tis article as been previously publised in a local Journal in Persian language). 5