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Full Paper Proc. of Int. Conf. on Advances in Design and Construction of Structures 2012

Sustainable Stormwater Management in Developing and Developed Countries: A Review Nivedita G Gogate1 and Pratap M Rawal2 1

Department of Civil Engineering, MIT, Pune, India Email: nivedita.gogate@mitpune.edu.in 2 Department of Civil Engineering, College Of Engineering, Pune, India Email: pushpak20@yahoo.co.uk Abstract - Traditionally, surface runoff was considered as an undesired water in developed areas which needed to be diverted as complete and as fast as possible from urban areas. In contrary to earlier concepts which considered surface runoff as clean water, the rainwater from impervious areas may be polluted with a series of contaminants. In the 1960s, management of stormwater quantity for flood prevention was the only imperative in the developed countries, but in subsequent decades objectives for stormwater management have diversified to include quality, ecosystem health, reuse, integration with urban design etc along with quantity and has inspired the development of novel stormwater management approaches designed to minimize impervious cover and maximize infiltration of rainfall known as LID in USA and WSUD in Australia. These techniques, if implemented at a watershed scale may offer a more sustainable solution to stormwater management. Though, sustainability is already recognized as a very important concept for the urban drainage management, there are, however many difficulties to effectively implement a sustainable urban stormwater approach in developing countries. Water resources have become the casualty of intensive urbanization leading to pollution of water bodies, lakes, rivers and contamination of precious groundwater. Thus, there is a need to integrate stormwater management in urban water planning. India, too needs to adopt sustainable practices in overall water management. This paper aims to present a review of the research work and projects carried out in developed and developing countries with respect to sustainable stormwater management. It also presents the analysis of stormwater quality in pune city in Maharashtra, India thus stressing the need for sustainable management of stormwater in India. Index Terms - Sustainable Development, Stormwater Management, Low Impact development, Water Sensitive Urban Design, BMP (Best Management Practice)

ecological point of view but also comprising social and economic aspects in the broad sense [1]. A sustainable urban water system, or stormwater system, is not only a question of problems and avoiding unwanted content in the water, it can also be a question of its potential usability as a water resource in society [2]. Stormwater drainage may not only be considered as systems to divert undesired water from urban areas, but also as a valuable element for landscaping the surrounding of buildings and roads [3]. This paper aims to present a review of various sustainable stormwater management studies being carried out in developed countries, and will also cover a summary of the research work carried out in developing countries, with special reference to India. II. CURRENT SCENARIO IN DEVELOPED COUNTRIES It was identified by many researchers that stormwater runoff from impervious surfaces is a key contributor to the collapse of healthy freshwater ecosystems in urban environments in both the United States (US) and Australia. This problem has been recognized for many years and has inspired the development of novel stormwater management approaches designed to minimize impervious cover and maximize infiltration of rainfall known as Low Impact Development (LID) in USA and Water Sensitive Urban Design (WSUD) in Australia [4]. In the 1960s, management of stormwater quantity for flood prevention was the only imperative, but in subsequent decades objectives for stormwater management have diversified to include other aspects such as quality, recreation & aesthetics, integration with urban design, ecosystem health and reuse, as shown in fig. 1.

I. INTRODUCTION Surface runoff from impervious areas is presently strongly discussed in view of future changes concerning its quantitative and qualitative management within urban water systems. Traditionally, surface runoff was considered as an undesired water in developed areas which needed to be diverted as complete and as fast as possible from urban areas. In contrary to earlier concepts which considered surface runoff as clean water, the rainwater from impervious areas may be polluted with a series of contaminants. During the last decade, increased attention has been paid to the issue of sustainability for urban water systems, not only from an 36 ÂŠ 2012 ACEE DOI: 02.ADCS.2012.1. 515

Fig.1. Prominent urban stormwater management discourses over the twentieth century [5]

Full Paper Proc. of Int. Conf. on Advances in Design and Construction of Structures 2012 The current spectrum of LID technologies spans from storm water retention and detention ponds, to pervious pavements, to open bioswales, to flatter grades, to green roofs, to rain barrels and rain gardens, to level spreader and vegetated filter strips, and to some local erosion-control measures. A literature review was conducted by the US EPA to determine the availability and reliability of data to assess the effectiveness of LID practices for controlling stormwater runoff volume and reducing pollutant loadings to receiving waters. In general LID measures are more cost effective and lower in maintenance than conventional, structural stormwater controls. Not all sites are suitable for LID. Considerations such as soil permeability, depth of water table and slope must be considered, in addition to other factors. Further, the use of LID may not completely replace the need for conventional stormwater controls [6]. Many researchers have worked on the concept of LID in terms of design, effectiveness in reducing runoff and pollutants, cost, etc. A brief summary of a few papers on this aspect is presented below. Reference [7] have developed a physically based Green Roof model for simulating the rainwater movement within the medium of green roof. Reference [8] presents a procedure for the consistent design based on unified sizing criteria and hydrologic evaluation of pervious concrete stormwater management systems. Reference [9] monitored the respective runoff from a 200-m2 permeable pavement test site and an adjacent 850m2 conventional asphalt road catchment in Auckland, New Zealand, concurrently between 2006 and 2008. Despite installation over relatively impermeable sub grade soils, and on an atypically high slope 6.0–7.4% and active roadway, the overall hydrologic performance of the permeable pavement was exceptional. According to Ref. [10], the water from roofs and roads represent by far the major contribution to urban surface runoff and that focus must be put on substances emitted from these surfaces, since roads cover 50–60%, roofs 25– 35%, and parking lots and driveways about 10–15% of the total impervious area on a regional basis. The analysis of road runoff shows clearly that most of the contaminants are bound to particulate matter. 80–90% of the heavy metals and PAH are present in particulate form. Therefore, removal of road dust by road cleaning or retention by treating the runoff water are efficient means to reduce pollutant loads. In Ref. [11], statistical analysis of stormwater runoff data for six catchments with different urban surface type including roofs, roadway, park, and residential/ commercial has been carried out. According to the results by PCA in all three catchments, from a perspective of pollution source of stormwater runoff, two potential pollution sources were identified. The first one concerned with TSS and TN, TP, TOC or COD, referred as nutrients losses, soil losses and organic pollutants discharge, the second was related to heavy metals including Zn, Pb and Cu, referred as heavy metals losses. The authors suggest structural stormwater improvement measures such as detention basins or sediment traps for the first pollution source (nutrients losses, soil losses and organic pollutants discharge). For the second pollution source (heavy metals), it © 2012 ACEE DOI: 02.ADCS.2012.1. 515

is concluded that it is not a major problem for urban stormwater runoff except Zn from iron roof runoff in Macau. It can be concluded that use of LID techniques does result in improving the quality of stormwater, though care has to be taken in designing the systems properly as has been shown in Ref. [12]. They have described design & operation of a novel storm water pond system. This BMP would only have complied with design guidelines if local environmental conditions such as spatial infiltration patterns had been fully considered. They concluded that, current international guidelines for the design and management of infiltration ponds require alterations to avoid system failure. Also, in another study in Ref. [13], a simple model is proposed for stormwater detention ponds. The model provides an estimate of contaminant residence time which can be related to hydraulic residence time in storm water detention ponds. According to Ref. [9], stormwater drainage may not only be considered as systems to divert undesired water from urban areas, but also as a valuable element for landscaping the surrounding of buildings and roads. Reference [14] describes the planning, design, and construction of multiuse drainage facilities for the Rock Creek development, a planned residential community in Colorado. The Master Drainage Plan provides for a regional system of storm-water channels and detention facilities that provide management of the increased runoff due to urbanization and multiple use of the channels and ponds for open space, recreational greenway corridors, wetland preservation, and riparian habitat. Reference [15] describes an ecological stormwater system in a residential area of China. The conventional stormwater management approach was replaced by an open trench system, which in combination of riparian zone, soft embankment and aqua plant pond forms an ecological system, presenting an enjoyable landscape. According to Ref. [4], the sustainable stormwater management approaches have been embraced by several cities, implemented as demonstration projects, and endorsed by several state and federal agencies. However, in most locations source control tools have not been widely implemented, and the vast majority of new stormwater management in the US and Australia remains in the form of conventional storm sewers with, perhaps, limited treatment by detention or retention basins. The authors say that decentralized stormwater management tools, such as LID or WSUD, may offer a more sustainable solution to stormwater management if implemented at a watershed scale.It can be observed that the best management practices (BMPs) for sustainable stormwater management can be evaluated with respect to various criteria, including: hydraulic efficiency, pollution retention, environmental impact, operation and maintenance, economic investment, social and sustainable urban living and other relevant criteria. As such, while trying to manage stormwater in a sustainable way, we need to adopt a multicriteria approach based on a set of indicators in decision making.The study in Ref. [16] deals with the application of a multicriteria analysis (MCA) approach to urban stormwater drainage management.The multicriteria analysis allowed 37

Full Paper Proc. of Int. Conf. on Advances in Design and Construction of Structures 2012 ranking the various alternatives based on criteria evaluation. Reference [17] describes the main results of several steps in developing a decision-aid tool that focus on a multicriteria procedure allowing the a priori evaluation of stormwater systems by the aggregation of economic-financial indicators with performance indicators, to the choice of adequate projects alternatives.

the future, reiterated the causes of the flooding as mainly the inadequate drainage system, rapid developments and loss of holding ponds, encroachment by the slums over the existing drains and decrease in the coastal mangrove areas. The city of Bhopal is facing severe water scarcity problem and over a period of time grave situation has cropped in. Reference [24] explores the present situation of water scarcity and demands for the future. Further they have worked out water potential zones (in the form of maps) as an outcome of the study. Similar efforts have been taken in the city of Chandigarh. The report published by Centre for Science and Environment, 2010 gives details of this project. Although fresh water resources are scarce in Hyderabad, it witnesses heavy floods during monsoons. The natural drainage has been affected due to various reasons, leading to frequent flooding of low-lying areas. The natural water courses have been illegally encroached upon. Land use planning is not concomitant with natural drainage patterns, which has led to the illegal encroachment of lakes. Thus, the Environmental Building Guidelines for sustainable storm water drainage have been developed to guide the stakeholders towards improved drainage management [25]. Reference [26] discusses flood risk reduction and management strategies in urban context with example of the Chennai city and draws attention of land-use planners and disaster management experts to integrate their efforts for better and sustainable results.

III. CHALLENGES IN DEVELOPING COUNTRIES There are many difficulties to effectively implement a sustainable urban stormwater approach in developing countries. In developing countries, the climatic and socioeconomic conditions bring difficulties to the use of solutions adopted in temperate areas. Problems such as greater capacity to generate runoff, greater erosive capacity, favorable conditions for the proliferation of vectors or carriers of tropical diseases, allied to uncontrolled urban expansion, precarious public works cleaning and inspection services, besides technically outdated and ill-planned storm drainage systems can complicate, and even make not feasible, the use of some devices and structures already in use elsewhere. Sediments and solid waste bring more complexity to this situation, contributing to the dissemination of diseases to the population [18, 19, 20]. According to Ref. [18], the use of technical solutions aiming to control runoff generation at its source is, in general, at initial stages of research and development, being seldom applied neither in public nor in private works. Though, efforts have started in this direction. The Bio-Ecological Drainage System (BIOECODS) is one such practical example of demonstration project of source control being implemented at USM’s Engineering Campus in Malaysia [21].

A. Pune City: A Case Study The population of Pune city (Maharashtra State) has increased three folds in the last 3 decades, thus resulting in multi fold increase in paved areas leading to increased runoff. Coupled with blocked natural drainage, this increased flow is causing flooding in many low lying areas. Also, the fluctuating amount of rainfall in the past few years in Pune has put additional pressure on the water supply system. The main cause of increased runoff is said to be the increase in impervious surfaces. According to the study carried out in 2009, there has been a two fold increase in built up area in less than a decade since 1999 [27]. The impervious surface area within a watershed is a very important parameter which decides as to how much will be the quantum of change in runoff. Thus, it can be concluded that due to rapid urbanization in Pune, the runoff quantity has also increased multifolds. With reference to the Environment Status Report (ESR), published by Pune Municipal Corporation [28], nallas are the highest polluted surface water sources as they receive raw sewage. The trends presented in the report indicate that the surface water quality is deteriorating in Pune city. As quality of stormwater is one of the major issues with respect to sustainable stormwater management systems, the water quality in the nallas flowing through Pune city is required to be analyzed. For this the drainage map of Pune city (fig. 2) was studied. According to this map, the city is divided into 23 drainage basins from ‘A’ to ‘W’. Out of these 23 basins, the basin ‘B’ (Kothrud) was selected for water quality analysis, since the type of landuse

IV. STORMWATER MANAGEMENT IN INDIAN CONTEXT The massive urbanization in India has resulted in generating huge quantity of stormwater which is wasted. This water can be harvested or can be used for recharging the groundwater. The other important factor is that lack of environmental considerations in city planning and construction has led to blocking of natural drainage system of the cities. Managing urban stormwater in developing countries poses huge challenges and the consequences of its neglect are severe. Thus, decision making to determine the preferred ways of sustainable stormwater management is becoming more complex. Thane Municipal Corporation (TMC) has taken up integrated drainage development program with the objective of developing a comprehensive stormwater drainage arrangement for systematic disposal of stormwater to avoid water logging and flooding in Thane [22]. Reference [23] describes Mumbai’s drainage system, the details of the 26 July 2005 severe (994 mm in 24 h) flooding, and the flood management measures being taken up by the city to mitigate such floods in the future. The Chitale committee, a fact finding committee set up by the Government of Maharashtra to identify the cause of flood and to recommend measures for © 2012 ACEE DOI: 02.ADCS.2012.1. 515

Full Paper Proc. of Int. Conf. on Advances in Design and Construction of Structures 2012 TABLE I. C HANGES IN LAND-USE PATTERN IN PUNE [27]

Fig. 2. Drainage Map of Pune

Fig. 2. Kothrud(B) basin drainage map

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Full Paper Proc. of Int. Conf. on Advances in Design and Construction of Structures 2012 is similar (residential) in most of the basins in the city. As can be seen from figure 3, there are 3 major nallas flowing through this basin (BN1, BN3 and BN7). Three sampling points were selected at the beginning of each of these nallas. Two sampling points were selected on downstream side of nalla BN1 and at the confluence of nallas BN3 and BN7 near Alankar Police Station. One sampling point was selected near Mhatre bridge where all these nallas come together and discharge into the Mutha river (figure 3). Grab samples were collected at @ 10 am on different days and the collected samples were immediately analysed for BOD5 (20oC) (Biochemical Oxygen Demand), COD (Chemical Oxygen Demand), Total Solids (TS) and Total Suspended Solids (TSS). The results of analysis (average values only) are presented in Table 2 below. Assuming intensity of storm as 74mm/hr, the design runoff (data obtained from PMC) and mass loading rate for each sampling location can be determined and is presented below. It can be concluded from the table above that water quality in all the drains in the Kothrud basin is very poor and is comparable to that of dilute to medium strength sewage. Hence, it is extremely essential to take appropriate steps to reduce the pollution level. If compared with the water quality criteria based on the Designated Best Use (Ref. Central Pollution Control Board), all these drains can be classified as having Below E class of water. Thus, Pune city needs to adopt a sustainable approach to manage the stormwater in order to improve its quality.

CONCLUSION The widespread degradation of water resources caused by pollution from urban runoff combined with the impacts of flooding and poor drainage of runoff has led to a critique of traditional approaches for the design & operation of urban drainage systems [20]. Rapid urbanization and uncontrolled urban migration have made urban water management a very challenging issue in India. The major problems faced by developing countries are identified as (i) Lack of consideration of complexities of environmental management, (ii) Lack of institutional co-ordination, (iii) Conventional centralized decision making processes, (iv Inadequate considerations of appropriate stormwater reuse options. According to Ref. [30], innovative and cost-effective methods are to be employed in urban water purification, stormwater harvesting and stormwater treatment to tackle the problem of water scarcity & pollution in India. LID techniques have been successfully used in many developed countries for improving their sustainability. Although, most of the developing countries including India are still much behind. Hence, it is proposed to study and review the various LID techniques to determine their suitability and adaptability in Indian condition. The detailed analysis at micro level for a watershed in Pune city will be carried out to determine the existing conditions, suitability of LID techniques and the overall management of stormwater in a sustainable way. Also, to manage stormwater in a sustainable manner, many criteria will have to be considered and many alternative solutions will have to be identified. Therefore, the objective of this work will be the development of a decision support tool for evaluating various sustainable stormwater management options in the current urban development scenario in India.

TABLE II. STORMWATER QUALITY IN KOTHRUD BASIN

REFERENCES [1] D. Hellstro¨m, U. Jeppsson, E. Ka¨rrman, “A framework for systems analysis of sustainable urban water management,” Environ Impact Assess Rev, vol. 20(3), pp. 311–322, 2000. [2] C. Sundberg, G. Svensson,, H. Soderberg, “ Re-framing the assessment of sustainable stormwater systems,” Clean Techn Environ Policy, vol. 6, pp. 120–127, 2004. [3] M. Boller, “New pathways for rainwater,” EAWAG News 44, 1998. [4] A. H. Roy, et al, “Impediments and Solutions to Sustainable, Watershed-Scale Urban Stormwater Management: Lessons from Australia and the United States,” Environmental Management, vol. 42, pp. 344–359, 2008. [5] Brown R. R., “Impediments to Integrated Urban Stormwater Management: The Need for Institutional Reform.” Environmental Management Vol. 36 (3), 455–468, 2005. [6] US EPA, “Low Impact Development – A Literature Review”, (2000).

TABLE III. MASS LOADING R ATE IN KOTHRUD BASIN

Full Paper Proc. of Int. Conf. on Advances in Design and Construction of Structures 2012 [7] Nian She and Joseph Pang, “Physically Based Green Roof Model,” Journal of Hydrologic Engineering, vol. 15(6), pp. 458-464, 2010. [8] S. S. Schwartz, “Effective Curve Number and Hydrologic Design of Pervious Concrete Stormwater Systems,” Journal of Hydrologic Engineering, vol. 15(6), pp. 465-474, 2010. [9] E. A. Fassman, Samuel Blackbourn , “Urban Runoff Mitigation by a Permeable Pavement System over impermeable Soils,” Journal of Hydrologic Engineering, vol. 15(6), pp. 475-485, 2010. [10] M. Boller, “Towards sustainable urban stormwater management,” Water Science and Technology: Water Supply, vol. 4(1), pp. 55-65, 2004. [11] J. Huang, et al, “Multivariate Analysis for Stormwater Quality Characteristics Identification from Different Urban Surface Types in Macau,” Bull Environ Contam Toxicol, vol. 79, pp. 650–654, 2007. [12] J. Zheng, H. Nanbakhsh, M. Scholz, “Case Study: Design and Operation of Sustainable Urban Infiltration Ponds Treating Storm Runoff,” Journal of Urban Planning And Development, vol. 132(1), pp. 36-41, 2006. [13] J. D. Weiss, Miki Hondzo, Michael Semmens , “Storm Water Detention Ponds: Modeling Heavy Metal Removal by Plant Species and Sediments,” Journal of Environmental Engineering, vol. 132(9), pp. 1034-1042, 2006. [14] M. R. Galuzzi, John M. Pflaum, “Integrating Drainage, Water Quality, Wetlands, And Habitat In A Planned Community Development,” Journal of Urban Planning And Development, vol. 122(3), pp. 101-108, 1996. [15] Wang Lin, Wang Weida, and Gong Zhaoguo, “Integrity of Local Ecosystems and Stormwater Management in Residential Areas,” Journal of Ocean University of China, vol. 5(4), pp 363-367, 2006. [16] C. Martin, Y. Ruperd, M. Legret, “Urban stormwater drainage management: The development of a multicriteria decision aid approach for best management practices,” European Journal of Operational Research, vol. 181(1), pp. 338-349, 2007. [17] M. Baptista, N. Nascimento, L. M. Castro, W. Fernandes, “Multicriteria evaluation for urban storm drainage,” SWITCH Scientific Meeting, University of Bermingham, UK, 2007. [18] AL. L. Silveira, J. A. Goldenfum, R. Fendrich, “Urban drainage

control measures,” In: urban drainage in humid tropics, Paris: UNESCO, pp.125-156, 2001. [19] AL. L. Silveira, J. A. Goldenfum, “Sustainable Approach applied for the Development of urban drainage manuals in brazil,” in: novatech 2004, Lyon - frança: graie, vol. 2, pp.1325 – 1332, 2004. [20] A. Rahman, “The state of urban drainage conditions and management in Aligarh city, India,” In: Proceedings of the 5th Novatech conference on Innovative Technologies in Urban Storm Drainage, GRAIE, Lyon, pp. 1303-1310, June 6-10, 2004. [21] Jonathan Parkinson and Mark Ole, “Urban Stormwater Management in Developing Countries,” IWA Publishing, London, 2008. [22] S.Nikam, Kapil Gupta, K. D. Lalla, “Integrated Approaches to Urban Drainage in Thane City,” Journal of Indian Water Works Association, vol. XXXXI (1), pp. 59-64, 2009. [23] Kapil Gupta, “Urban flood resilience planning and management and lessons for the future: a case study of Mumbai, India,” Urban Water Journal, vol. 4: 3, pp. 183 - 194, 2007. [24] A. Bharat, D. Sharma, S. Gupta, “Facilitating Rain Water Harvesting and Storm Water Management for Recharging Groundwater in Urban Areas- A Case of Bhopal Region,” NOVATECH 2007. [25] Hyderabad Metropolitan Development Authority (HMDA), “An Abridged Manual on Environmental Building Guidelines for Hyderabad Metropolitan Area,” 2009. [26] A. K. Gupta and S. S. Nair, “Flood risk and context of landuses: Chennai city case,” Journal of Geography and Regional Planning, Vol. 3(12), 365-372, 2010. [27] Desai C.G., Patil M.B., Mahale V.D. and Umrikar B. , “Application of remote sensing and geographic information system to study land use / land cover changes: a case study of Pune Metropolis.” Advances in Computational Research, vol. 1(2), 10-13, 2009. [28] PMC (2010), “Environment Status Report.” [29] PMC (2007), “SEA Report (Strategic Environmental Assessment Report).” [30] K. S. Nair, “Socio-economic and environmental issues associated with urban water management in india,” International Symposium on New Directions in Urban Water Management, UNESCO Paris, 12-14 September 2007.