Status of Bangalore Wetlands: Strategies for Restoration, Conservation and Management
Kiran. R. and Ramachandra. T.V.*
Centre for Ecological Sciences, Indian Institute of Science, Bangalore 560 012, India


Management is the manipulation of an ecosystem to ensure maintenance of all functions and characteristics of the specific wetland type. The loss or impairment of wetland ecosystem is usually accompanied by irreversible loss in both the valuable environmental functions and amenities important to the society [Zentner, J. 1988]. Appropriate management and restoration mechanisms need to be implemented in order to regain and protect the physical, chemical and biological integrity of wetland ecosystems. In this context a detailed study of wetland management and its implications on the socio-economic aspects is required from biological and hydrological perspective.

In Bangalore as in most urban centers environmental pressures on wetlands are created by human activities, by changing land use in the watershed area, pollution from point and non-point sources, soil compaction, loss in interconnectivity and solid waste dumping, etc., all affecting the natural functioning of wetlands. Protecting these wetlands existing functions proves to be incredibly complex as it involves building a partnership among the various agencies, working in a co-ordinated effort in addressing the common goal of minimizing the human-induced changes that affect the hydrology, biogeochemical fluxes and the quality of wetlands. The problems of wetlands in Bangalore can be broadly summarized as,

  • Hydrologic alterations, includes changes in the hydrologic structure and functioning of wetland by direct surface drainage, de-watering by consumptive use of surface water inflows, unregulated draw down of unconfined aquifer from either groundwater withdrawal or by stream channelisation for various human activities.
  • Increased sedimentation, nutrient, organic matter, metals, pathogen and other water pollutant loadings from both storm water runoff (non point source) and wastewater discharges (point source).
  • More insidious atmospheric deposition of pollutants into these waterbodies mainly by the vehicular and industrial pollution  both from within and towards the sub-urban industrial complexes.
  • Introduction or change in characteristic wetland flora and fauna (exotic) as a result of change in the adjacent land uses deliberately or naturally, changing water quality, etc.

Wetlands are an integral part of watershed; their position, natural and anthropogenic activities, hydrology, climate, geology of the region and site-specific factors influence their natural functioning. The over exploitation of wetlands in Bangalore in using them as receptacles of untreated sewage, runoff from developed urban and agricultural areas, changing land use within the watershed etc., have resulted in rendering the ecosystem in peril. This deteriorating water quality due to pollution has led to spawning of mosquitoes, due to absence of predators such as Gambusia affinis, killifishes (Fundulus spp. ), etc., which preys on mosquito larvae[Buchsbaum, R. 1994]. An Integrated Pest Management (IPM) involving bio-regulation approach could possibly control mosquitoes rather than draining wetlands.

Guidelines for wetland management

The wetland management program generally involves activities to protect, restore, manipulate, and provide for the functions and values emphasizing both quality and acreage by still advocating sustainable usage of them [Walters, C. 1986.]. Management of wetland ecosystems requires an intense monitoring, increased interaction and co-operation among the various agencies (state departments concerned with environment, soil, natural resource management, public interest groups, citizen groups, agriculture, forestry, urban planning and development, research institutions, government, policy makers, etc). Such management goals should not only involve buffering wetlands from any direct human pressures that could affect the wetlands normal functions, but also in maintaining important natural processes that operate on them that may be altered by human activities. Wetland management has to be an integrated approach in terms of planning, execution and monitoring requiring effective knowledge on a range of subjects from ecology, economics, watershed management, and planners and decision makers, etc. All this would help in understanding wetlands better and evolving a more comprehensive solution for long-term conservation and management strategies.

  1. The management strategies should involve protection of wetlands by regulating inputs using water quality standards (WQS) promulgated for wetlands and such inland surface waters to promote their normal functioning from the ecosystem perspective, still deriving economic benefits by sustainable usage.
  2. Urban wetlands provide multiple values for suburban and city dwellers [Castelle, et al., 1994]. The capacity of a functional urban wetland in flood control, aquatic life support and as pollution sink implies a greater degree of protection. It provides a resource base for people dependent on them. When dealing with such common resources, some of the important factors to be considered for developing a management strategy for wetlands are,
    • Data relating to the current ecological condition of the lakes in Bangalore is inadequate. This necessitates an immediate need to create a database on the wetland types, morphological, hydrological and biodiversity data, surrounding land use, hydrogeology, surface water quality, and socio-economic dependence, and highlight the stress these systems are subjected to in the given context.
    • Conduct regular water quality monitoring by involving institution, colleges and regulating bodies of surface water, groundwater and biological samples. Such programs helps in providing technical, hydrologic support and information which aid in better understanding of these systems and formulating a comprehensive restoration, conservation and management programs.
    • Development of water quality database, data analysis and disseminating information by involving local institutions and accessibility to all users. This can be achieved through,
      1. Exchange of data across departments involved in the program, easy accessibility to regularly and continuously monitored data;
      2. Update technical guidance and water quality maps at regular intervals and indicate quality determinant parameters;
      3. Analyse and discuss case studies of water quality issues;
      4. Provide spatial, temporal and non-spatial water quality database systems.
    • Correct non-point source pollution problem and administer the Pollution Prevention Program through the environmental awareness programs.
  3. Creation of Buffers zones for Wetlands protection: Creating buffer zones limiting anthropogenic activities around the demarcated corridor of the wetland could revive its natural functioning. The criteria for determining adequate buffer size to protect wetlands and other aquatic resources depend on [Castelle et al. 1994].
    • Identifying the functional values by evaluating resources generated by wetlands in terms of the economic costs, etc.
    • Identify the magnitude and the source of disturbance, adjacent land use and project the possible impact of such stress in the long term, etc.
    • Buffer characteristics - vegetation density and structural complexity, soil condition and factors.

A fully formed functional In-buffer must consider the magnitude of the identified problems, resource to be protected, and the function it has to perform. Such a buffer zone could be consisting of diverse vegetation along the perimeter of waterbody, preferably an indigenous one serving as trap for sediments,   nutrients, metals and other pollutants, reducing human impacts by limiting easy access and acting as a barrier to invasion of weeds  and other stress inducing activities [Stockdale, 1991].

  1. Community support: Wetland management, restoration or conservation of wetland ecosystem requires an integrated, broad-based inter-agency partnership all working towards a common goals involving the educational institutions, forest department, Bangalore Development Authority (BDA), City Corporation, Irrigation department, Public Works Department (PWD) and Pollution Control Board for a successful conservation and management of wetlands. Also active participation of local community, conservation organisations, NGO's, and citizens’ groups with active support from the media at all levels of planning, executing and monitoring is required for implementation of measures to meet the set goals.
  2. Schools and colleges: Wetlands requires a collaborated research involving natural, social and inter-disciplinarian study aimed at understanding the various components, such as, monitoring of water quality, socio-economic dependency, biodiversity and other activities as an indispensable tool for formulating long term conservation strategies [Kiran et al., 1999]. This needs multidisciplinary-trained professionals in educating the essence of wetland importance involving the local school, colleges and research institutions.  Initiate educational programs aimed at rising the levels of public awareness and comprehension of aquatic ecosystem restoration goals, and methods.

The active participation from the schools and colleges in the vicinity of the waterbodies may value the opportunity for hands-on environmental education further entailing setting up of laboratory facilities at site. Regular monitoring of waterbodies (with permanent laboratory facilities) provides a vital inputs for  conservation and  management.

  1. Regulatory bodies: An interagency regulatory body comprising personnel from departments involved in urban planning (Bangalore Development Agency, Bangalore City Corporation, etc.), resource management (Forest department, Fisheries, Horticulture, Agriculture, etc.), and  regulatory bodies such as Pollution Control Board (PCB), local citizen groups, research organisations and NGOs  would help in evolving effective wetland programs covering significant components of the watershed, that needs a co-ordinated effort from all agencies and organisations involved in programs affecting the health of wetland ecosystems directly or indirectly.
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