Lakes and Ponds: Pollution Abatement and Environmental Sustainability

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1 Lakes and Ponds: Pollution Abatement and Environmental Sustainability National Environmental Engineering Research Institute Dr. Rakesh Kumar, Chief Scientist and Head, Mumbai Regional Center Phone: /

2 Urban Lakes: Under Constant Threat What has gone wrong!!! Degradation of quality Untreated sewage discharge Solid waste disposal Eutrophication Floating weeds PROTECTION METHODS Degradation of quantity Abstraction of Water for variety of usages Encroachment Drainage & Alternate Land Use Silt influx from degradation of catchment area

3 Water Bodies Current Status-Across India

4 Ground water Recharge: Lakes Help!

5 Qualities of a Healthy Lake.. High Water Clarity [ No floating matter ] No Stench No Floating Weeds No Floating Solid Waste High Dissolved Oxygen (D. O.) High Biodiversity

6 Prevent 1 st Step: Prevent v Municipal and/or Industrial Effluent disposal v Solid waste disposal v Idol Immersion v Introduction of exotic and/or invasive species v Encroachments v Over-exploitation of resources like fish, water v Catchment Area degradation v Slope Instability

7 Cure is Necessary.. Eutrophication Floating Treatment Wetlands Floating weeds Removal Brine Spray Physical Removal Introduction of biological predator (insects, fungi, herbivorous fish)

8 Sedimentatio n Low D.O. Dredging: When and Where?? Does Aeration always Help??

9 A Healthy Ecosystem in the Lake = A Healthy A Lake

10 2 nd Step: Treatment of Inputs Any unwarranted flow of solids and liquids need to be treated and suitably discharged Liquid Waste can become an additional source of water Achieve discharge standards: Below 10 ppm of BOD

11 11 INPUT TREATMENT USING CONSTRUCTED WETLAND

12 3 rd Step: Peripheral and In-situ Treatment Water bodies (lake or impounded water in dam) need peripheral arrangement for: prevention of silt and sediments Prevention of nutrient from rainy runoffs In-situ removal of contaminants

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15 The Shahadara Lake Rejuvenation Project Sewage Water will be treated by the Phytorid Technology based on constructed wetland and will be used for Rejuvenating the lake in the Shahadara locality of East Delhi

16 Floating Treatment Wetland: In-situ treatment

17 Advantages.. Low Cost No Power Requirement Low on maintenance Eco-friendly

18 Lake/Pond Bhujale Lonar Telebandha Kot Lake Shahdara Status Ongoing Completed Phase I On progress Under implementation

19 Eco-Unfriendly Activities Solid waste disposal Nirmalya disposal Fish feeding Idol Immersion

20 Environmental Issues Pre-monsoon water quality poor; water was high in suspended solids, floating debris, foul smell, BOD and COD It appeared faint yellow-green in color and the clarity was poor Local fishermen around complained of itching when their skin came in contact with the water No aquatic plants or birds observed Fishes like magur and guppy have been introduced

21 Some Work of NEERI s Technology for Lakes and Nalla Waste Water Treatment

22 NEERI s Floraft Technology Pilot scale implementation of NEERI's Floraft technology, which is our improvised version of the Floating Treatment Wetland technology has been undertaken at the Bhujavale Talao in Malad (W), Mumbai Common native aquatic plants planted in Florafts Phragmites karka Typha latifolia Justicia americana Eleocharis Alternanthera

23 Bhujale Talao: Location of Study Area Dimensions: m, m, m, and m Approximately feet deep at the center Roughly bowl shaped

24 Mumbai Reels under Water Pollution Stress

25 Florafts are made of PVC pipes and plastic nets of about 5ft by 5ft size Florafts are given adequate thickness through thermocol paddings and double net layers so that plants are adequately supported

26 Florafts can be tethered to nearby trees or poles Or, allowed to float freely

27 Idol-in-Net Technology

28 Water Quality of Bhujale Pond (mg/l) DO Pre-Monsoon Post-Monsoon Pre-Immersion Post-Immersion Sampling stations (mg/l) Am-N Pre-Monsoon Post-Monsoon Pre-Immersion Post-Immersion Sampling stations (mg/l) TSS Sampling stations Pre-Monsoon Post-Monsoon Pre-Immersion Post-Immersion (mg/l) TDS Sampling stations Pre-Monsoon Post-Monsoon Pre-Immersion Post-Immersion

29 (mg/l) BOD Sampling stations Pre-Monsoon Post-Monsoon Pre-Immersion Post-Immersion 200 COD Pre-Monsoon Post-Monsoon Pre-Immersion Post-Immersion (mg/l) Sampling stations

30 OPERATION & MAINTENANCE Little or no maintenance required on a daily basis as the system is biological and requires no electricity or sophisticated set-up Manpower is required for harvesting excess emergent biomass every few months Local wetland plants will be needed for re-populating floating rafts Briquetting and sale of harvested biomass ADVANTAGES In-situ method of water treatment Low cost, aesthetic and ecofriendly No electricity requirement No skilled manpower required Natural Oxygen production Reduction in BOD, NO 3 -N, TSS and coliforms has been reported New land mass for use by all kinds of creatures including fish and aquatic birds Sequestration of carbon and other greenhouse gases Harvested biomass can be sold as briquettes

31 Nabi Lake Under Consideration Lonar Lake Lonar Lake (under threat), Maharashtra Lake Area: 3 Ha Phytorid Capacity 500 KLD Plant commissioned Phytorid Plant on Nabi Lake Entire Sewage from Lonar

32 Telibandha Lake, Raipur Lake Area: 11 Ha Phytorid Capacity 2 MLD Proposed to develop 3 plant at periphery Second Phase started

33 Kot Lake Brahmapuri, Maharashtra Phytorid capacity 450 kld project design initiated

34 Shahadara Lake, Delhi 3 MLD Capacity Phytorid Beds for Rejuvenation of an 8 acre surface area Lake which is currently totally dried up Existing Conditions Proposed Outlay

35 Proposed design of Phytorid for Nag Nadi (Nalla) Already 500,000 lit/day already being treated and used (Punjab Rao Krishi Vidyapeeth) Estimated land area required: 2563 m 2 For a plant capacity of 1000 m 3 /day Entire length of the plant: 267m For a plant capacity of 1000 m 3 /day Length of the Phytorid bed: 184 m Dimension: 1.5m depth X 184m length X 8m width Project completion period: 12 months

36 The Result. Birds among visitors More varieties of fish Clean waters and no stink No itch for swimmers

37 Study Area Thane: One of the cities in Mumbai Metropolitan Region Lat Long: N E Also known as City of Lakes (35 lakes in the city) Sampling Site: Siddheshwar Lake ü Location: Near Uthalsar Ward Office ü Area: 3 Hectares ü Type of settlement: Completely urbanized water body Ref: TMC s ESR,

38 Water Quality Index Seasonal Variation in WQI Values 350 WQI Values W S M PM Season W= Winter, S =Summer, M= Monsoon, PM= Post Monsoon ü Based on the seasonal WQI values for Siddheshwar lake, it can be concluded that the water quality of this lake is very poor in all the seasons ü Water is unsuitable (based on drinking standards)

39 Conclusions Without understanding the social connectivity with water bodies, its difficult to solve issues Protection methods (modern) are actually harming them Input control technologies (sustainable and power free) In-situ Control Continuous monitoring with local participation

40 Dream or Reality?!