Bhoj Wetland Proiect
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DRAFT: Not for Citation or Distribution Bhoj Wetland 1 Experience and Lessons Learned Brief for 2 Bhoj Wetland 3 4 Dr. M.S. Kodarkar 5 Head, Indian Association of Aquatic Biologists 6 Hyderabad, India 7 8 9 1. INTRODUCTION : 10 11 South Asia, home to over one fifth of the world’s population is facing water crisis. This 12 region is in the grip of flood and draught cycles and there is a need to have a long term 13 strategy for management of its water resources. Big and small water bodies in the form of 14 lakes and reservoirs dot landscape of south Asia. These ecosystems impound precious 15 freshwater and make up the most easily accessible source for many human uses. 16 Historically, major cities in this region flourished in geographical regions with assured 17 water supply that sustained civilization for centauries. Unfortunately, last half of 19" 18 Centaury is witness to large scale degradation of environment in general and water 19 resources in particular, due to a number of anthropogenic factors like un-precedented 20 population growth and consequent urbanization, industrialization and chemical intensive 21 agriculture (Kodarkar, 1995). The first victims of this degradative process were the lakes 22 and reservoirs in the vicinity of urban areas that underwent large scale pollution due to 23 sewage and/or industrial effluents and toxic chemicals. In most of the cases nutrient 24 enrichment led to eutrophication (Edmondson, 1991) with a number of negative 25 manifestations like : 26 27 1. Permanent algal blooms and poor water quality 28 2. Wild growth of macrophytes like water hyacinth and loss of biodiversity 29 3. Breeding of vectors like mosquitoes and snails and impacts on public health 30 4. Foul smell due to gases like hydrogen Sulphide (H2S), Ammonia (NH3) etc. 31 5. Fish/Bird kills and 32 6. Ground water pollution 33 34 Further, there was drastic alteration in morphometry and water holding capacity of lakes 35 and reservoirs due to dumping of garbage, solid waste and silt. The process is further 36 aggravated by encroachments and unauthorized construction activities in the catchment 37 and on the lake bed. When compared with rural, the impact of degradation is more severe 38 in urban areas due to high population density. 39 40 Due to ecological, economical and recreational potential of lakes, there is an urgent need 41 of their protection, rehabilitation and conservation as precious natural resource. By 42 suitable remedial measures a lake can bestow a number of benefits like : 43 44 1. Charging of groundwater table : Water bodies by acting as percolation source 45 recharge the groundwater table. In India in the last two decades there is constant fall 46 of water table in urban areas due to poor recharge on account of wanton destruction of 47 surface water resources. Depletion of water table may even endanger the food security 48 due to loss of agricultural production for want of adequate groundwater for irrigation. 49 1 DRAFT: Not for Citation or Distribution Bhoj Wetland 1 2. Aquaculture : If properly utilized urban water bodies can be effectively utilized for 2 fish production. Unfortunately the planners give very low priority to this aspect and 3 many water bodies are rendered useless due to heavy pollution from domestic sewage 4 and consequent eutrophication. Apart from supplying food, aquaculture can be an 5 effective measure for reducing nutrient load on a water body. 6 7 3. Flood regulation, moderation and control : Almost all cities in the country 8 experience flooding even after moderate rains. This is happening mainly due to 9 inadequate drainage facilitties in haphazardly developing urban zones and destruction 10 of water bodies. The latter use to act like buffers moderating the impact of flooding. 11 12 4. Conditioning of the climate : Urban areas are developing into concrete jungles with 13 very less greenery leading to hotter climate. A water body acts as an effective climate 14 conditioner and maintains temperature at lower levels in the surrounding areas. 15 16 5. Sustenance of colloidal water for vegetation : Greenery depends on colloidal water 17 in the soil which is replenished by surface water resources. 18 19 6. Sustenance of biodiversity : It is universally accepted fact that survival of man is 20 dependent on survival of plant and animal species which form mosaic of biodiversity. 21 Areas like estuaries and wetlands are hotspots of productivity and flora-fauna 22 interaction. Thus water bodies in general play an important role in sustenance of 23 biodiversity. 24 25 7. Recreational sites : Lakes and reservoirs can be protected as aqua-parks and 26 recreational centers generating jobs and services. 27 28 8. The sediment of most of the lakes is rich in organic matter and can be effectively 29 used as manure for kitchen gardens and parks. 30 31 9. The livelihood of lake dependent communities like washer men and small dairy 32 farmers belonging to weaker sections of the society depends on healthy lakes. These 33 communities are one of the key stake holders of these resources. 34 35 10. Community asset with cultural and educational value: 36 37 To achieve this, there is a need of a clear cut lake protection strategy as an integral 38 component of national water policy. 39 40 41 42 43 44 45 46 47 48 49 2 DRAFT: Not for Citation or Distribution Bhoj Wetland 1 Fig. 1. Upper Lake and Lower Lake (Bhoj Wetlands), Bhopal, Madhya Pradesh, India. 2 3 4 Fig. 1. Bhoj wetlands, Bhopal, Madhya Pradesh, India 5 6 Table 1. Profile of the lakes (physical). 7 Item UPPER LAKE LOWERLAKE Constructed in 11th Century A.D. Late 17th Century Type of dam Earthen Earthen Latitude 23012'- 23o16'N 23 o 14'- 23 o 16'N Longitude 77 o l 8' - 77 o 23' E 77 o 24'- 77 o 25'E Catchment area (Sq.lcm.) 361 9.6 Submergence area at FTL 36.54 0.90 (Sq.km.) Full'Fank Level (MSL) (m) 508.65 499.88 Dead Storage Level (MSL) (m) 503.53 499.88 Storage capacity (million cum.) 117.05 4.3 Maximum depth (m) 11.7 9.4 Source of water Rain water & Sewage Rain water, Seepage from Upper Lake and Domestic Sewage Main use of water Potable water supply Washing and Boating 8 Lakes of Bhopal (Fig. 1., Table 1.) : 9 10 Bhopal, the historical city and the capital of state of Madhya Pradesh, can be called 11 limnological capital of India as pioneering work in this field was initiated on two lakes 12 dominating the landscape of this urban sprawl. Further, these lakes are perhaps the first 13 ecosystems that were subjected to intensive management and lessons learnt in this field 14 can be applicable in whole South Asian region. 15 16 The historic Upper Lake impounded in the 11th century is a classic prototype of urban 17 water body. With well-protected catchment, its water quality was of potable standard up 18 to recent times (Singh. and Anandh, 1996). However, in the last two decades of 20th 19 Centaury as the city grew many sections of the Lake were encircled by habitation. These 20 developments generated the anthropogenic pressures on the Lake thus accelerating the 3 DRAFT: Not for Citation or Distribution Bhoj Wetland 1 process of eutrophication and making the water unfit for human consumption without 2 proper treatment (IS, 1984). 3 4 Table 2. Water quality of lower lake in Bhopal (1991-92). 5 Parameter Range Temperature CC) 19-30 pH 7.15-9.7 Transparency (cm) 14-98 Conductivity (µS at 250C) 259-374 Total Dissolved Solids (TDS) mg/L 86-169 Hardness (mg/L) 68-154 Chlorides (mg/L) 14.9-88.9 Total phosphorus 0.106-1.02 Total nitrogen (mg/L) 1.08-1.46 6 7 The Lower Lake, constructed in the 19th Century is an integral part of upper lake 8 ecosystem and a source of raw water for the urban development and domestic water needs 9 like washing, bathing etc. As in the case of many urban water bodies all over India, the 10 Lower Lake was subjected to all kinds of negative anthropogenic stresses. Further, drastic 11 alteration of its morphometry and degradation of water quality (Table 2) prompted the 12 authorities to initiate the action plan for rehabilitation, protection and conservation of the 13 two lakes. The outcome of this initiative was Bhoj Wetland Project, which is funded by 14 Japan Bank of International Cooperation (PBIC) and is a fine example of Indo-Japanese 15 co-operation in the field of ecology and environment. 16 17 3. BHOJ WETLAND PROJECT: 18 19 The Lake Conservation and Management Project also known as Bhoj Wetland Project, 20 envisages tackling of various issues associated with conservation and management of the 21 Upper and Lower Lakes of Bhopal, under a multi-pronged strategy. Although these issues 22 are deeply interrelated and inter-linked, for operational and management convenience, 23 they are addressed under different independently executed sub-projects. The proposed 24 action plan is not one time quick solution but should trigger a chain reaction so as to make 25 the management sustainable. The identified 16 sub-projects are as follows : 26 27 I . Desilting and Dredging of the Lakes 28 2. Deepening & Widening of the Spill Channel 29 3. Restoration of the island 30 4. Catchment Area Treatment (Artificial wetland) 31 5. Afforestation, Creation of Buffer Zones 32 6. Construction of Check dams, Silt traps, Toe walls & Cascading 33 7. Construction of Garland drains 34 8. Prevention of Pollution (sewerage schemes) 35 9.