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CONSERVATION OF URBAN LAKES IN HYDERABAD METROPOLITAN AREA
Jayesh Ranjan, IASVice-Chairman, HUDA
Hyderabad - Profile
Located between 17°21' - 17°71' N Latitude and between 78° 21' -78°76'E Longitude with an average altitude of 560 m above MSL.
Hyderabad Metropolitan Area comprises 8500 sq. km.Topography – Rocky, undulating with gentle slopes, red gravely soils Tropical climate with annual rainfall of 800 mm (under semi-arid) Decadal growth rate - 37 %Ranked 6th in population among the metropolitan cities in India.
HYDERABAD URBAN DEVELOPMENT AUTHORITY
The Authority is constituted in1975 under Urban areas (development) act 1975.HUDA is a statutory Planning Authority to develop Master Plan for planned development and controlled growth of urban areas.
To plan for a sustainable development of Hyderabad urban agglomeration.To develop policy framework, zoning regulations and land use plan.To plan and implement infrastructure facilities like road network and overall transportation plan.To plan for sustainable environmental management.
LAKES OF HYDERABAD
About 400 big & small lakes in HUDA area.
169 lakes notified by HUDA for protection and conservation of water spread area with no activity in 30 m buffer around the water bodies.
INDIA
Andhra Pradesh
URBAN LAKES – DRAINAGE MAP
India
Hyderabad Urban Development Authority
Hydrological regime & role of urban lakes
Urbanization has led to loss of water bodies resulting in increased runoff
Lakes contribute significant additional recharge to the ground water regime due to infiltration
Over-exploitation of ground water due to urbanization leads to rapid depletion of ground water level
Hydrological regime & role of lakes
During the past few years there is a fall in water level of 1-2 m per year all over the City
Polluted water body causing unhygienic and health hazards for lake neighborhood.
The worst ground water scenario is experienced by apartment complexes
Problems faced by urban lakes
Tampering inflow & outflow channels.
Urbanization.
Change of land use.
Washing clothes
Cattle Wash
Industrial effluents.
Indiscriminate dumping of debris and garbage.
Continuous flow of untreated waste waters.
Invasive weed - throttling the lake ecosystem
Inappropriate shoreline development (Encroachments)
Pollution due to Idol Immersion
Need for restoration of urban lakes
To harvest the precious rainwater and augment shortfall in water supply needs of Hyderabad
To moderate the flood risk by interconnecting the lakes
To utilize the wastewater by treatment process during the dry weather and maintain lake water balance
To improve the scope for recharge of ground water within the influence zone of the lakes
Need for restoration of urban lakes
To improve the health conditions of people living in the lake surroundings.
To enhance the biodiversity in and around the lakes.
To induce recycling and reuse of wastewater after treatment for non-potable uses for gardening and industrial purpose.
Develop local economy through eco-tourism activities at lakes.
HUDA has taken up the task of restoration of lakes in the Hyderabad Metropolitan area to conserve the water bodies and to increase the ground water table with clean water. In the first phase, out of 169 large water bodies notified, 87 lakes are being taken up under Green Hyderabad Environment Programme (GHEP) from 2004 onwards
Categorization of lakes for development
• Category – I (more polluted) - 18 nos • Category – II (moderately polluted) - 69 nos
These lakes are categorized based on certain criteria like degree of pollution, size of the lake, proximity to habitation, etc.
Baseline WorkDetailed survey of the lake and its surroundings and preparation
of the lake plan.Bathymetry of the lake for area - volume of the lake.
Database on watershed and the ground water quality and water table in all seasons. Preparation of the Catchment area plans.
The flow measurements of all incoming dry weather flows and outflows of the lakeThe flow measurements of all incoming wet weather flows and
outflows of the lake.Daily lake water level recordings.
Pan evaporation data from the Meteorological dept.Rainfall data from the Meteorological dept. for calculating the
storm water runoff from the catchment area into the lake.
Cont..
Baseline WorkDry weather flows for the projected population for the year 2031
is calculated by using census data.
The capacity of Sewerage Treatment Plant is fixed based on the quantity of minimum flow required into the lake to maintain its water balance which is equal to the maximum water loss due to evaporation and percolation under no outflow condition during the dry season when the evaporation is highest. Water quality analysis of inflow, lake water and outflow of the
lake for all parameters such as BOD, COD, DO, Total Nitrogen, Total Phosphorus and trace metals etc.The sediment analysis of the lakebed in different layers
depending up on the nutrient values in the sediment.Socio economic study of the lake surroundings for identification
of direct and indirect dependents within the vicinity of the lakes.Biodiversity study of the lake for compiling on the current
biodiversity.
Restoration works at lakes
Category - IFormation of peripheral bund along the shore line of the lakeDesilting the lakebed by dredgingStrengthening and widening of main bund Restoration of surplus weirs and sluices Construction of STP for treating the raw sewage and letting the treated water into the lake to maintain the lake water to the desired level
Restoration of inflow and outflow channels
Diversion of excess sewage by laying pipelines.
Beautification of lake bunds and periphery with landscaping and plantation.
Restoration works at lakes
Restoration works at lakes
Category - IIFormation of peripheral bund along the shore line of the lakeDesilting the lakebed by dredgingStrengthening and widening of main bund Restoration of surplus weirs and sluices Restoration of inflow and outflow channelsPlantation on Lake bunds
Process Details of The STP
Interception, diversion and collection of sewageScreening of floating matter & gritDe-Nitrification (Biological process)Extended Aeration with fine pore diffused membraneFlocculation with Alum dosing for phosphorus removal
Settling by Plate SettlersChlorination & Filtration
Clear treated effluent to wetland where special type of plants viz. cattails and bullrush are planted for removal of further phosphates and nitrates
Tertiary Treatment Process
Wetland
Lake
Raw sewage
A View of the STP
DN TankAeration
Flocculation tankPlate settlers
Pressure filter
Sludge drying beds
Power room
Lab
Restoration of Safilguda Lake
Before Intervention
After Intervention
Restoration of Langerhouse Lake
Before intervention
After intervention
A View of Saroornagar LakeDescription BOD COD DO TKN Total P
Lake Water Before Intervention 65.00 212.00 3.40 14.00 5.87
Lake Water After Intervention 25 92 6.2 9 1
Standards <10 <50 >5 <5 <1
A View of Langerhouse LakeDescription BOD COD DO TKN Total P
Lake Water Before Intervention 120.00 270.00 0.40 29.00 5.22
Lake Water After Intervention 14.00 32.00 5.40 4.15 0.80
Standards <10 <50 >5 <5 <1
Description BOD COD DO TKN Total P
Lake Water Before Intervention 82.00 370.00 0.40 29.00 5.60
Lake Water After Intervention 16.00 42.00 5.60 6.15 1.20
Standards <10 <50 >5 <5 <1
A view of Pedda Cheruvu, Nacharam
A view of Resident friendly STPs
Mir Alam Tank
Saroornagar Lake
Trees, Bamboo and ground cover helps in increasing the Bio-diversity as well as self purification by absorption of phosphates and Nitrates
Floating macrophytes like pistia and duckweed help in removal of inorganic Nitrogen and Phosphorus in the wetland
Biological Treatment Facility
Lake Landscapes
Provides enhanced aesthetics to the lakes.
Increases opportunity for gainful employment through eco-tourism
Exclusive Bird Island created at Safilguda Lake
Rich faunal and floral Bio-diversity in the midst of the city
Bio-diversity of Restored Lake
A Paradise for Birds in the midst of urban built-up area
Lake eco-system and wetland contribute a lot to the bio-diversity
Improvement in the Lake water quality from Hyper-eutrophic condition to Mesotrophic condition
Increase the Biodiversity of the Lake
Increase in pisciculture activities
Employment generation by Eco-tourism activity
Increase in recreational facilities and water sports.
Improvement in the groundwater quality
Improvement in human health of lake surround
Improved aesthetics
Enhancement of property values in the lake surroundings
OUTCOME : SOCIO-ECONOMIC BENEFITS