Selected Topics in Energy, Environment, Sustainable Development and Landscaping Changes in water quality in the lakes along Colentina River under the influence of the residential areas in Bucharest CRISTIAN IOJĂ1*, DIANA ONOSE1, ADINA CUCU1, LUMINITA GHERVASE2 1Centre for Environmental Research and Impact Studies, University of Bucharest, 1 Blvd. Nicolae Balcescu, sector 1, Bucharest, 010041, ROMANIA, [email protected], www.ccmesi.ro 2National Institute for Optoelectronics, 409, Str. Atomistilor, Măgurele, Ilfov county, ROMANIA Abstract: Water represents an important receiver of the environmental problems generated by human settlements, being the environmental component which transfers many of the environmental externalities (wastewaters, waste, heat, various substances). In Bucharest, an essential part of the urban ecosystem is represented by the lakes along the Colentina River, which occupy 3.25% of the city surface and have a high importance in flood protection, recreation, improvement of environmental quality and receiving some of the city’s problems. To assess changes in lakes water quality on the Colentina River it was organized a network formed by 33 monitoring points situated on 9 lakes. The monitored indicators were physical (temperature, conductivity, turbidity, transparency, pH), oxygen indicators (dissolved oxygen, chemical oxygen demand) and nutrients related (ammonium, nitrates, nitrites). The results were correlated with the characteristics of the residential areas situated in the lakes proximity (typology, wastewater management). There was noted a degradation in the water quality for the lakes which have in the shore areas individual residential and an improvement when the shores are covered by green spaces, collective residential, industrial areas, and even open fields. Degradation of water quality means an increased risk of eutrophication and thus a decrease in the value of its use in various urban purposes. Therefore, to implement the Water Framework Directive objectives and to improve the quality of life in the peripheral areas of Bucharest, situated along the lakes of Colentina River, is necessary to increase the sewage network coverage and to limit the uncontrolled waste disposal. Key-Words: water quality, residential areas, sewage, wastewaters, environmental degradation sources, Water Framework Directive, Bucharest 1 Introduction environmental problems characteristic of large urban Sustainable development of urban environments is a areas: urban wastewater with varying degree of process that changes the resources exploitation and biochemical loading, solid waste, heat excess, different utilization, the investments and technology development organism [2]. All these problems reduce the economic direction and how institution work in order to increase utility of water resources and turn them into vectors for economic welfare, social equity and environmental propagation and attraction of urban issues: insalubrity, quality on average and long term [1]. overgrowth of different animal and plant species In a sustainable city, the ability to produce wealth populations (mosquitoes, aquatic plants, etc.), increased equally depends on the capacity of protecting and peripheral effects, poverty, and loss of competitiveness preserving the natural capital against overexploitation and economic attractiveness of the area [5]. Many of (including water resources) and on the institutions these problems are enhanced by residential areas or are efficiency and society flexibility to assume consumption reflected in the housing quality [3]. patterns that are efficient form economical, social and Therefore, the relationship among water quality and ecological point of view [2]. In this context, a residential areas is a frequently approached theme in sustainable residential area is characterized by providing international conventions on environmental protection. optimal living conditions but, also, by a low aggression Agenda 21 integrates between environmental problems a against the environment [3]. series of issues related to residential areas. Control of Water is an environmental component essential for diseases transmission, reduction of disease risk due to sustainable development of human settlements, pollution and hazards and protection of vulnerable important both through its useful side and its aggressive groups are important for the communities’ sustainable one (floods, salinisation) [4]. Beyond its values as a development, all of them being related with the water resource, water is an important receiver of component [6]. ISSN: 1792-5924 / ISSN: 1792-5940 164 ISBN: 978-960-474-237-0 Selected Topics in Energy, Environment, Sustainable Development and Landscaping Convention on Human Settlements (Habitat I) achieves concerning environmental protection and water quite actual problems of human settlements with management [2]. significant projection in environmental quality, namely Bucharest is located in Vlasia Plain, being characterized water supply and recreation. Spontaneous residential by a lithological substrate composed of friable rocks and development, generally met in peripheral areas, is very a temperate continental climate with excessive nuances important, especially because they don’t benefit from which affect the water and chemical flows of rivers minimal accessibility to services that ensure safety, crossing this area [9]. In terms of territorial evolution, hygiene and health. Bucharest has characteristics of cities with uncontrolled Convention Habitat II proposes two main themes of urban development: industrial areas changes situated global importance: A real shelter for everybody and inside the city or in its peripheral areas, by replacement Sustainable human settlements in an urbanized world. of the industrial activities with large shopping centers Convention recognizes that the problems of human and/or residential spaces; increase of the built space settlements have a multidimensional nature, inadequate density on the expense of open fields, increase of the shelter being in connection with social and economical differences concerning facilities and services in problems. Convention promotes, for the first time at luxurious and peripheral areas [3]. political level, the concept of urban regeneration, encouraging conservation, land rehabilitation and maintenance of oxygen generating surfaces, landscape, 2 Problem Formulation etc with particular value. Development of built areas with residential function United Nations Organization concern for improving resulted in a significant decrease in water quality of housing quality in human settlements was continued by lakes in the north and east of Bucharest. This process is Resolution S-25/2 – Declaration on cities and other largely emphasized by the poor coverage of the public human settlements in the new millennium, signed in sewage system. Therefore, a large proportion of 2001. Like Habitat I and II Conventions, it insists on household wastewater is directly or indirectly discharged providing drinking water resources for everybody and in the lakes along Colentina River, contributing to water on facilitating access to basic infrastructure and quality degradation and health issues emergence. municipal services (sewage, waste management, transportation). At European Union level, because of the growing 2.1 Colentina lakes and nearby residential pressures on water resources have been promoted areas legislative instruments for their protection and Colentina River crosses Bucharest from north-west to sustainable management, the most important being the east, on a length of 34 km, being 100% anthropic Framework Directive 2000/60/EC. This Directive modified. The area in proximity of nowadays lakes was provides the necessary framework for water sustainable initially represented by a series of wetlands and marshy management, proposing a quantitative and qualitative areas, which raised great hygiene problems [10]. management of water and aquatic ecosystems in order to The transformation of this area by draining the marshes achieve the “good ecological status” of waters in and establishing the lakes was originally conceived as European Union until 2015 [7], [8]. The implementation part of Bucharest green belt, and the area was partially instrument of the Framework Directive, governed by arranged as urban parks (initially Herastrau and Bordei Article 13 and Annex VII, is represented by the River parks, and after Tei, Plumbuita and Pantelimon parks). Basin Management Plan. Nowadays, on the Bucharest administrative territory, In Romania, the framework for sustainable management Colentina River is formed by 11 lakes which had as of water resources is provided by the Water Law, which primary purpose the protection of urban center against implements, details and particularizes the provisions of flooding and the improvement of the sanitary conditions the Water Framework Directive. (Table 1). In Bucharest, water resources management is performed Subsequently, to these functions were added those of by the Romanian Waters National Administration recreation, water supply for different urban purposes (responsible for the qualitative and quantitative (irrigation of green areas, reserves for fire fighting, street management of water surface), district city hall washing, feeding fountains, etc) [11]. (responsible for shores) and different economical agents The average area of the lakes is 90.5 ha [33.260], useful with interests in recreation, fishing or sport activities. 3 water volume