EVALUATION OF QUALITY OF WASHOFF STORMWATER IN SELECTED URBAN IMPERVIOUS SURFACES

Submitted byKothalawala C.D. (RU/E/2009/094)Kumara P.G.R.W. (RU/E/2009/098)

SupervisorsMs. N.S. Miguntanna Dr. C.KariyawasamExamination CommitteeDr. C.KariyawasamDr. (Ms) W.K.C.N. DayanthiMs. T. N. Wickramaarachchi

Department of Civil and Environmental EngineeringFaculty of EngineeringUniversity of RuhunaJune 20132

ACKNOWLEDGEMENT

First we wish to express our sincere gratitude to our project supervisors, Dr Cyril Kariyawasam and Mrs. Nadeeka Migunthanna for their guidance in our research work. And also we express our gratitude to Mr. Jayalath C.P.G, to his faith of the project.We wish to thank Dr H.P.Sooriyarachchi, the head of the department, Department of Civil & Environmental Engineering, Faculty of Engineering, University of Ruhuna and Dr. (Mrs.) Subashi De Silva, the coordinator of undergraduate research project for their great support to success the project.Our appreciate goes to all the technical officers and non-academic staff members of Department of Civil and Environmental Engineering for giving their support to success our research work.

Kothalawala C.D (RU/E/2009/094)Kumara P.G.R.A (RU/E/2009/098)Faculty of EngineeringUniversity of Ruhuna

CONTENTSACKNOWLEDGEMENTiCONTENTSii1. INTRODUCTION11.1 SIGNIFICANCE OF THE RESEARCH21.2 AIMS & OBJECTIVES2CHAPTER 232. LITERATURE REVIEW32.1 BACKGROUND32.2 IMPACT OF URBANIZATION32.3 INTRODUCTION TO IMPERVIOUS SURFACES52.3.1 Storm water runoff from road surfaces52.3.2 Storm water runoff from roof surfaces62.4 STORMWATER POLLUTANTS62.4.1 Nutrients62.4.2 Oils and grease72.4.3 Suspended solids72.4.4 Heavy metals72.4.5 Organic compounds72.4.6 Microbial contaminants82.4.7 Toxic chemicals82.5 WATER QUALITY PARAMETERS92.5.1. Physical Parameters102.5.2 Chemical Parameters10CHAPTER 3133. PROPOSED METHODOLOGY133.1 LITERATURE REVIEW133.2 STUDY AREA AND SELECTION OF STUDY SITES133.2.1 Study Area133.2.2 Selection of Study Sites13Figure 1: Study site within faculty premises143.3 COLLECTION OF SAMPLES AND TESTING143.4 DATA ANALYSIS164. TIME PLAN17REFERENCES18LIST OF FIGURESFigure 1: Study site within faculty premises .13Figure 2: Sample collection locations within faculty premises14

LIST OF TABLESTable 1: Sources of Contaminants in Urban Storm Water Runoff. 09

Proposal Report_i CHAPTER 11. INTRODUCTION

Much of the rainfall in watersheds having forests and pastures is absorbed into the porous soils (infiltration), is stored as ground water, and moves back into streams through seeps and springs. Thus, in many rural areas, much of the rainfall does not enter streams all at once, which helps prevent flooding (M. J. Pouraghniaei, 2002). According to the same author when areas are urbanized, much of the vegetation and top soil is replaced by impervious surfaces such as roads, parking lots, and pavement disturbing the natural infiltration. Then rainfall runoff that used to be absorbed into the ground must be collected by storm sewers that send the water runoff into local streams. One of the most important causes of water quality deterioration in urban areas is urban stormwater runoff. Even during small rain events, surfaces such as streets, driveways, roofs and parking lots produce stormwater runoff due to its impervious nature. A variety of pollutants which are accumulated on these surfaces are removed by wash-off with storm water runoff leading to a considerable increase in pollutant loading to receiving water bodies. (N.S. Mingunthenna, 2009) The degradation of receiving water quality due to polluted urban storm water runoff is an important issue and impacts on a significant proportion of the urban population. Depending on the land use, stormwater pollutants have different characters. During a rainfall event, the impacts of high flows and discharges of pollutants on receiving water bodies are superimposed on the hydrologic, physic-chemical and biological characteristics of an urban catchment. Urban stormwater runoff will produce both, short-term and long-term changes in receiving waters leading to habitat instability and chemical toxicity (Goonethilake A. & Thomas E., 2003). The storm runoff pollution has negative consequences on our aquatic resources (streams, lakes, estuaries, rivers, aquifers and other water bodies) which are most valuable assets of every nation. Change in flow, increased sedimentation, higher water temperature, lower dissolved oxygen, degradation of aquatic habitat structure, loss of fish and other aquatic populations, and decreased water quality due to increased level of nutrients, metals, hydrocarbons, bacteria and other constituents are examples for the resulting negative impacts (Ahmed N., 2011)Impervious surfaces accumulate pollutants deposited from the atmosphere, leaked from vehicles, or windblown in from adjacent areas. During storm events, these pollutants quickly wash off, and are rapidly delivered to downstream waters. Quality of stormwater is typically measured in terms of a range of quality parameters and his knowledge is required to understand the effect of runoff on the receiving water quality and to develop appropriate mitigation measures.1.1 SIGNIFICANCE OF THE RESEARCHDue to the severity of the problem of polluted storm water runoff, mitigation actions on storm water pollution are of crucial importance. In this context, accurate knowledge on storm water runoff pollution is essential to develop appropriate mitigation strategies. However, the effectiveness of such mitigation actions is limited due to the lack of knowledge on pollutant processes, namely, pollutant build-up and wash off and key quality parameters.Urban storm water quality, widely investigated around the world, has been monitored very much less in our study area, Galle, Sri Lanka. Storm water runoff is a significant problem in urban areas in southern province. Because of the higher percentage of impervious surfaces in urban areas it can generate the higher amount of storm water runoff during rainy season. The study area belongs to the wet zone of the country and hence has ample precipitation throughout the year. Purpose of this research is to evaluate the characteristics of wash off from selected urban impervious areas. Roads, roofs and parking lots have been selected to this study, which are typical impervious surfaces in urban land uses and hence to contribute to the knowledge needed for mitigating storm water pollution. Based on the understanding generated from the data analysis, recommendations will be provided to improve the effectiveness of storm water quality mitigation strategies.1.2 AIMS & OBJECTIVESOBJECTIVES; :1. To evaluate physical characteristics of washoff storm water in selected impervious surfaces1. To evaluate quality of washoff storm water in selected impervious surfaces

AIMS; :1. Identify of key pollutant indicators which represent washoff storm water quality.1. Determine of characteristics of pollutants wash-off stormwater from selected impervious surfaces.1. Determine of quality of washoff storm water in selected impervious surfaces

CHAPTER 2 2. LITERATURE REVIEW2.1 BACKGROUNDWhat is stormwater runoff? It Stormwater runoff is the rain and melting snow that flows off streets, rooftops, lawns, and farmland. The flowing water carries salt, sand, soil, pesticides, fertilizers, leaves and grass clippings, oil, litter, and many other pollutants into nearby waterways (Stormies clean water tips). Hence an essential need for washoff stormwater management practices is accurate knowledge of runoff qualityUrban storm water quality, widely investigated around the world, has been monitored very much less in Galle, Sri Lanka even though urban stormwater runoff quality has been investigated widely since the 1980s in many countries (Levsen et al 1990; Voegilin 1998; Bravo et al, 1997; Buchili et al 1997). Storm water runoff is a significant problem in urban areas in southern province. Because of the higher percentage of impervious surfaces in urban areas it can generate the higher amount of storm water runoff during the rainy season. In this area of the country has more precipitation throughout the year, due to this area belongs to the wet zone of the country.Because of the higher rain fall intensity, during rainy season the surface runoff generations cause substantial problems to people. The problems caused depend on the type and area of impervious surface. There are so many impervious surfaces in the urban area. But the most significant surfaces are roads roofs and parking lots (R Yufen et al 2008). Therefore in this research, about the quality of the runoff of above surfaces will only be determined.2.2 IMPACT OF URBANIZATIONWith the rapid urbanization, impervious surfaces are expanding very quickly. Because of the higher percentage of impervious surfaces such as roads, roofs and parking lots can generate excess runoff during small intensity of rain fall. Development and urbanization affect not only the quantity of stormwater runoff, but also its quality. Development increases both the concentration and types of pollutants carried by runoff. As it runs over rooftops and lawns, parking lots and industrial sites, stormwater picks up and transports a variety of contaminants and pollutants to downstream waterbodies. The loss of the original topsoil and vegetation removes a valuable filtering mechanism for stormwater runoff. (Columbia County Stormwater Management Design Manual) According to Bravo et al (1997), when the rain water washes the roads, roofs and parking lots considerable amount of pollutant was brought in to receiving water bodies. These wash off pollutants can make sever damage to the natural water bodies (Sagret, 1994). The primary pollutant sources of urban catchments are: Industrial process Construction and demolition activities Corrosion of materials Litter Street and transportation.(Pitt1997; pitt et al 1995)Because of the urbanization lot of industries are located in the urban area and generate waste in all three states, solid, liquid and gaseous. Fine pollutants are transport by the wind and can settle over the impervious surfaces in the dry period. There are several industries, such as garments, fertilizer manufacturing, cement factories and etc. within the study area. Hence, that it is important to consider the effect of the storm water quality to identify the effect of those factories on the runoff water quality within the study area.Urban development within a watershed has a number of direct impacts on downstream waters and waterways. These impacts include: Changes to stream flow Changes to stream geometry Degradation of aquatic habitat Water quality impacts (Columbia County Stormwater Management Design Manual)The urbanization of watersheds poses threats to water quality from both point and nonpoint sources of pollution. Point sources are locations where specific pollutants are discharged directly into lakes, streams, estuaries, and coastal waters via pipes and other conduits. Point sources include factories, power plants, and sewage treatment plants. Nonpoint source pollution is generated from broad land areas, and pollutants are delivered to water bodies via stormwater and snowmelt runoff. It generally takes several runoff events to transport nonpoint pollutants from their source areas to receiving lakes and streams. (Kent B. Barnes, John M. Morgan III, and Martin C. Roberge)Water quality degradation in urbanized watersheds starts when development begins. Erosion from construction sites and other disturbed areas contribute large amounts of sediment to streams. As construction and development proceed, impervious surfaces replace the natural land cover and pollutants from human activities begin to accumulate on these surfaces. During storm events, these pollutants are then washed off into the streams. Stormwater also causes discharges from sewer overflows and leaching from septic tanks. There are a number of other causes of non-point source pollution in urban areas that are not specifically related to wet weather events including leaking sewer pipes, sanitary sewage spills, and illicit discharge of commercial and industrial wastewater and wash waters to storm drains.Due to the light weight and cost effectiveness, most of new buildings, especially in industrial and commercial areas tend to use metallic roofing materials. Metals like Cu and Zn are used for the roof surfaces including gutters and down pipes. Al and Pb also use for coating and types of fittings. Weathering and other physical damages help to release these heavy metals to rain water with the contribution of its low pH value (Gobel et al., 2006).Finally, development and urbanization affect not only the quantity of stormwater runoff, but also its quality. Development increases both the concentration and types of pollutants carried by runoff. The cumulative impact of development and urban activities, and the resultant changes to both stormwater quantity and quality in the entire land area that drains to a stream, river, lake or estuary determine the conditions of the water body. With the increment of the urban development, it is required to concern about water quality standards.2.3 INTRODUCTION TO IMPERVIOUS SURFACESImpervious surfaces are manmade surfaces, roofs, roads, parking lots etc. In urban areas the most critical impervious surfaces are roofs, roads and parking lots. Mainly these surfaces are covered by impermeable material such as asphalt, concrete or asbestos. These surfaces can generate surface run off. Paving surface with asphalt and concrete makes these surfaces like desert in hydrological and climate manner. Storm water washes over paved, sparsely vegetated urban surfaces in much the same manner as it did over the desert landscape. Intense over urban area can generate large volume of runoff quickly even flash flood followed by relatively dry condition (Christopson, 2001).2.3.1 Storm water runoff from road surfacesNumber of studies has investigated the availability or transport of pollutant constituent of road surfaces. (Sartor and Boyed 1972, Shaheen et al 1975, Ellis and Revitt 1982 and Bell et al 1996) have all investigated the pollutant constitution of road surfaces. As a source of contaminant, vehicles are the both direct and indirect sources. The contaminants that are directly sourced to vehicles are those related to the operation of vehicles frictional wear and normal combustion by product. On the other hand, the indirectly source contaminant are those that are transported to roads through normal activity; such as sediment transport by construction sites, farms and dirt roads. So that more than the 95 % of sediment on a given highway originated from sources other than the vehicle themselves JE Ball (2000).2.3.2 Storm water runoff from roof surfacesRoof runoff contributes the solid liquid and gaseous pollutant. According to Bandara (2012), these gaseous products would initially contribute to atmospheric pollution and return to the roof surface due to wet deposition during rain fall. According to Gromaire at al (1999) the high concentration of dissolved metal measured on roof run off can make its infiltration hazardous. The experimental work for four deferent types of roof materials (interlocking clay tiles, flat clay tiles, Zink sheets and slate) have been done. Samples of storm water runoff have been collected from the gully. According to the results, it has been found that SS, COD and BOD5 concentration are very much lesser than the concentration values for the road runoff.2.4 STORMWATER POLLUTANTSImpervious surfaces accumulate pollutants deposited from the atmosphere, leaked from vehicles, or windblown in from adjacent areas. During storm events, these pollutants quickly wash off, and are rapidly delivered to downstream waters. Stormwater carries the pollutants from the surface on which it travels and it is more polluted in urban areas than rural areas. Larm (1994) described three basic parameters influencing compositions of runoff: type of the surface on which it travels antecedent dry period and original pollution load in rainfall. Antecedent dry period is considered the key factor in determining the storm water pollutants deposited on the catchment surface available for wash off during storms. (Ahmed N., 2011) The pollutants which are often investigated in stormwater are nutrients, oils and grease, suspended solids, heavy metals, organic compounds, microbial contaminants. These are described below.2.4.1 NutrientsThe primary nutrients are nitrogen and phosphorus. Nitrate enters the storm water from different land use activities. It comes from fertilizers, decomposition of natural rocks and soils, detergent used to wash car on the streets and from the animal faeces. Nitrogen (N) and phosphorus (P) released from the arable land in dissolved or particulate form not only degrade the soil nutrients stock and lower soil productivity, but also cause eutrophication in water bodies. Fertilizers, animal wastes, failing septic systems, detergents, road de-icing salts, automobile emissions, and organic matter such as lawn clippings and leaves are all contributors to excessive nutrient levels in urban and agricultural storm water runoff. (Ahmed N., 2011)2.4.2 Oils and greaseOils and grease are common components of storm water runoff pollutants because their sources are abundant: streets and highways, parking lots, food waste, storage areas, heavy equipment and machinery storage areas, and areas where pesticides have been applied. The familiar sight of a rainbow-colored puddle or trickling stream in parking lots, driveways, and street gutters is a reminder of the presence of oils and greases in storm water runoff. (Ahmed N., 2011)2.4.3 Suspended solidsSuspended solids are the largest pollutant constituents in storm water. They accumulate and have significant negative impacts on the environment, including increment in turbidity. Sources of sediment include washoff of particles that are deposited on impervious surfaces, the erosion of stream banks and construction sites. Both suspended and deposited sediments can have adverse effects on aquatic life in streams, lakes and estuaries. Sediments also transport other attached pollutants. (Maryland Department of the Envionment Stormwater Manual, Chapter 1)2.4.4 Heavy metals Stormwater runoff from urban areas contains significant loads of metal elements such as Lead, Zinc, Cadmium, Copper, Chromium and Nickel. The important activities which generate heavy metals are vehicular traffic, combustion of fossil fuels and lubricants and industrial procces. (Goonethilake A. & Thomas E., 2003) Typical sources of heavy metals are industrial wastes, solid wastes, landfill leachate, corroding metal pipes and storage tanks. Heavy metals are not biodegradable and are harmful to the aquatic environment. Heavy metals show a distinct accumulation behavior on solid surfaces. Heavy metals in dissolved form in the storm water runoff are adsorbed on the solid surfaces. (Kern et al., 1992) The pH of rainfall has a significant impact on the desorption of pollutants absorbed on particulates. 2.4.5 Organic compounds Plant debris, food waste, and certain chemical wastes fall into a category of water pollutants known as oxygen demanding substances. The common impact of organic matter is the reduction in dissolved oxygen in water due to microbial oxidation. (Goonethilake A. & Thomas E., 2003) If dissolved oxygen levels in water become too low, aquatic animals can become stressed or die. Animal wastes, food wastes, leaves and twigs, and other miscellaneous organic matter carried by stormwater runoff into surface water can lead to reduced oxygen levels (Ahmed N., 2011). Gromaire-Mertz et el (1999) and sartor and Boyd (1972) have identified street surfaces as a major contributor of oxygen demanding materials to receiving waters.(Goonethilake A. & Thomas E., 2003)2.4.6 Microbial contaminants As the stormwater passes through impervious surfaces it carries many human and non-human pathogenic bacteria. The degree of pathogens bacteria pollution is more or less directly proportional to the imperviousness of the surface. (Ahmed N., 2011)2.4.7 Toxic chemicals Motor oil, lead from gas and auto exhaust, zinc from roof drains and tires, and pesticides in stormwater runoff may kill aquatic organisms or impair their health, growth or ability to reproduce (Stormies Clean Water Tips). Table 1 shows the sources of above mentioned contaminants in urban stormwater runoff.

Table 1: Sources of Contaminants in Urban Storm Water RunoffContaminantContaminant Sources

Sediment and FloatablesStreets, lawns, driveways, roads, construction activities, atmospheric deposition, drainage channel erosion

Pesticides and Herbicides

Residential lawns and gardens, roadsides, utility right-of-ways, commercial and industrial landscaped areas, soil wash-off

Organic MaterialsResidential lawns and gardens, commercial landscaping, animal wastes

Metals

Automobiles, bridges, atmospheric deposition, industrial areas, soil erosion, corroding metal surfaces, combustion processes

Oil and Grease/HydrocarbonsRoads, driveways, parking lots, vehicle maintenance areas, gas stations, illicit dumping to storm drains

Bacteria and Viruses

Lawns, roads, leaky sanitary sewer lines, sanitary sewer cross-connections, animal waste, septic systems

Nitrogen and PhosphorusLawn fertilizers, atmospheric deposition, automobile exhaust, soil erosion, animal waste, detergents

2.5 WATER QUALITY PARAMETERSWater quality parameters can be divided into sub categories as mentioned below.i) Physical parametersii) Chemical parametersiii) Biological parameters2.5.1. Physical ParametersThe most important physical parameters which should be tested for urban storm water are; Turbidity Total solid Total suspended solidTurbidity - Turbidity is a measure of the extent to which light is either absorbed or scattered by suspended material in water. As the absorption and scattering are influenced by both size and surface characteristics of the suspended materials, turbidity is not a direct quantitative measurement of suspended solids. The measurement of turbidity is based on comparison of the intensity of light scattered by a sample as compared to the light scattered by a reference suspension under the same condition. (Metcalf & Eddy, 1991)Total Suspended Solids (TSS) - Total Suspended solid is an indication of the amount of erosion that took place nearby or upstream. As well suspended solids can block pipe system and storage system. This parameter would be the most significant measurement as it would depict the effective and compliance of control measures. Source of suspended solids include wet and dry decomposition, constructions and demolition operations and erosion by wind and water. (Bandara, 2012)2.5.2 Chemical ParametersThe most important chemical parameters which should be tested for urban storm water are; Alkalinity Hardness Heavy Metals Chloride pH Nitrogen COD

Alkalinity- Alkalinity is not a pollutant. It is a total measure of the substances in water that have "acid-neutralizing" ability. Basically it measures the concentration of carbonates, bicarbonates and hydroxide compounds of Ca, Mg, Na and K. Alkalinity is measured by titration with acid. High level of alkalinity imparts a bitter taste to water and not acceptable for public consumption. (Metcalf & Eddy, 1991)Hardness- Concentration of all major ions increased in the roof runoff compared to rainwater with the exception of ammonium. Potassium and calcium concentrations were particularly elevated through the weathering of the concrete tile roof, and to lesser extent clay roofs. Chloride, Nitrate, Sulphate and sodium concentration were measured by (Fster 1998) were approximately twice that found in the rainwater, however there was little difference in concentrations between roof types (P. Kennedy and Jeniffer 2001).Heavy Metals - Trace metals such as copper, lead and zinc are commonly detected in rood runoff. In general, the roofing material is the major influencing factor on trace metal concentrations (Good 1993). For an example, galvanized iron roof tend to have high concentration of zinc and lesser concentration of cadmium in the runoff. The surrounding environment also contributes trace metals. Wet and dry deposition are important source as concentration on trace metal in urban and industrial locations tend to be higher than rural sites with the same roof type (Thomas and Greene 1993). Most metal surfaces exposed to the environment will be subjected to atmospheric corrosion during which corrosion product (Patina) layer is formed (Karlenet al. 2002).Chloride Chlorides are the common constituents of all natural water. Chlorides are not harmful or toxic even at higher concentrations. The higher concentration of chloride imparts salty taste to water. The permitted level is 200 mg/L in portable water.Nitrogen - Nitrogen is one of the most common elements in the world. All living plants and animals need it to build proteins. Nitrogen and phosphorus are both nutrients. High levels of nitrogen may make some people sick, especially young babies. Because nitrogen is a nutrient like phosphorus, the effects of this nutrient on water are almost the same. Like phosphorus, extra nitrogen in water leads to rapid plant growth. Too many plants living in the water can lead to some bad results.COD- Chemical Oxygen Demand is created by biodegradable as well non-biodegradable substances. COD is used to measure the strength of contamination of non-biodegradable organic matters or compounds.

2.5.3. Biological ParametersThe most important biological parameters which should be tested for urban storm water are; BOD Total coliform Fecal coliformBOD- Biochemical oxygen demand, or BOD, measures the amount of oxygen consumed by microorganisms in the process of decomposing organic matter in stream water. Normally, at the laboratory, biological oxygen demand for 5 days is measured and it is called as BOD5. Measurement of BOD is a direct representation of the extent of pollution in natural water bodies and portable water. (Bandara, 2012)

Total coliform - Total coliform are used as an indicator of microbiological contamination of water. An indicator organism is not a measurement of dangerousness. But indicates the likely presence of fecal contamination, and hence the possible presence of pathogens in the sample. Total coliform are a sensitive measure of possible fecal contamination, but they do not confirm the presence of fecal contamination. (Bandara, 2012)

Fecal coliform- Fecal coliform bacteria are found in the feces of human beings and other warm-blooded animals. By themselves, fecal coliform bacteria do not usually cause disease. They occur naturally in the human digestive tract and aid in the digestion of food. However, when a human being or other warm-blooded animal is infected with disease, pathogenic (disease causing) organisms are found along with fecal coliform bacteria. (Bandara, 2012)

CHAPTER 33. PROPOSED METHODOLOGYThe proposed research methodology consists of four steps as follows;1. Literature review2. Selection of study site3. Collection and testing of water samples4. Data analysis3.1 LITERATURE REVIEWA comprehensive literature review is carried out focusing on stormwater pollution aspects in urban land uses and key water parameters, which are used in the evaluation of water quality. 3.2 STUDY AREA AND SELECTION OF STUDY SITES3.2.1 Study AreaAs the study area of this research, Galle area is selected. Galle is the capital of the southern province, Sri Lanka with a population of about 1,020,000. Average annual precipitation in Galle is 2500mm and average annual temperature around 27.4 0C with a peak temperature of 30.6 0C. As the administrative city and an ancient city of Southern province, a wide range of activities take place in the city which includes tourism, agriculture, fisheries and different types of industrial and commercial activities. Quality of stormwater which collected from representing selected impervious surfaces within Galle area will be tested.3.2.2 Selection of Study SitesSelection of field study sites is one of the important components of the research methodology. The selection of study sites for this research was based on the fallowing criteria; Easy accessibility to the sites Minimum disturbance to traffic Sufficient slope for the flow of runoff Traffic conditions in the area Serviceability of the catchment

As the first step, the faculty premise was selected as one study site. According to above criteria, three sites for sampling roof runoff (roofs of canteen, lecture hall building & civil department), three sites for roads, and one site for parking lot (close to administration building) were selected as shown in Figure 1. All selected three roofs, and roads are made from same material. The places for collecting samples were selected as to distribute the locations throughout the faculty.

Figure 1: Study site within faculty premises

As next steps, it is expected to collect washoff stormwater samples from Pettigalawaththa junction and Galle bus-stand area.3.3 COLLECTION OF SAMPLES AND TESTINGBased on the knowledge gathered from literature review, outlet of the building drain pipe for the roof runoff and drain gullies for the road and parking lots runoff was selected to collect washoff stormwater samples. The sample collecting locations within faculty premises is shown in figure 2 Figure 2. Samples will be collected to polypropelene containers.Comment by DELL: Add a photo and remember to update your list of figures after adding the photo. And cite it befor in the text.Figure 2: Sample collection locations within faculty premisesComment by DELL: Please specify these three location separately. Ex: Rainwater down pipe at the canteen etc. Remember to update your list of figures after changing namesMinimum of five days of antecedent dry days will be maintained in between each sampling event. The selection of antecedent dry days was based on the findings of research literature on build-up of pollutants on urban impervious surfaces varies with the number of antecedent dry days. (Bandara, 2012) Even though the researchers have noted that build-up may vary with the antecedent dry days, it will not be considered as a variable in this study.The samples will be started to collect at least 10 minutes after the beginning of rainfall event to ensure that the first flush is not collected as noted by several research studies that first flush contains higher amounts of pollutants compare to latter part of runoff. (Bandara, 2012) Collected samples will be carried to Environmental laboratory, Faculty of Engineering as soon as possible.Considering all pollutants that discussed above, we suggest that tests should be conducted for fallowing physical, chemical & biological parameters.Comment by DELL: Should be in passive form1. Electrical conductivity2. Turbidity3. Total solids-TSS, TDS, VS4. Oil and grease5. Chemical Oxygen Demand (COD)6. Total Organic Carbon (TOC) (Cannot be done in our laboratory)7. Biochemical Oxygen Demand (BOD5)8. pH9. Total hardness10. Total Alkalinity11. Chloride12. Total Phosphorous13. Total Nitrogen14. Total coliform15. Fecal coliform

3.4 DATA ANALYSISData analysis will be carried out using both univariate and multivariate data analysis techniques. In this commonly use data analysis software will be used. The generated runoff quality data will be compared with the standard water quality guidelines. Finally, based on the findings, recommendations and suggestions will be provided to improve the effectiveness of storm water quality mitigation strategies.

CHAPTER 44. TIME PLAN

REFERENCESBarrios A., June 2000, Urbanization and Water QualityArthur McGarity1, Optimization for Urban Watershed Management: Stormwater Runoff and Nonpoint Pollution ControlGoonathileke A., Thomas E., July 2003, Water Quality Impacts of UrbanizationBandara T.G.J.S, Bandara Y.M.D.L.Y., 2012, Evaluation of Harvested Rainwater Quality as a Drinking Water Source in Urban Landuses in Southern Province Sri LankaColumbia County Stormwater Management Design Manual, Chapter 1 Section 1.1D. Wicke, T. Cochrane, A. OSullivan, University of Canterbury, Department of Civil and Natural Resources Engineering, Private Bag 4800, Christ-church, New Zealand, An Innovative Method for Spatial Quantification of Contaminant Buildup and Wash-off from Impermeable Urban SurfacesKent B. Barnes, John M. Morgan III, and Martin C. Roberge Department of Geograph and Environmental Planning Towson University Baltimore, Maryland 21252, Impervious Surfaces And The Quality Of Natural And Built EnvironmentsMaryland Department of the Environment Stormwater Manual, Chapter 1M.C. Gromaire-Mertz, S. Garnaud, A. Gonzalez, G. Chebbo, 1990, Characterization of Urban Runoff Pollution in ParisMetcalf & Eddy, 1991, Third edition, Wastewater Engineering, Treatment, Disposal & Reuse, McGraw Hill Ahmed N., Runoff water quality from a green roof and in an open storm water system, TVVR-10/5020 ISSN-1101-9824Migunthanna N.S., 2009, Faculty of Build Environment and engineering Queensland University of technology, Determining a set of surrogate parameters to evaluate urban stormwater quality