1 / 24

UMIAM LAKE FACING EXTINCTION!

UMIAM LAKE FACING EXTINCTION!. Umiam Lake - Snippets. Reservoir of Umiam Hydel Project – Stage I. Commissioned in 1965 – Ist Hydel Project of NE. Area –10.27 sq km; Area of catchment –220 sq km

altessa
Download Presentation

UMIAM LAKE FACING EXTINCTION!

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. UMIAM LAKEFACING EXTINCTION!

  2. Umiam Lake - Snippets • Reservoir of Umiam Hydel Project – Stage I. • Commissioned in 1965 – Ist Hydel Project of NE. • Area –10.27 sq km; Area of catchment –220 sq km • Engineering marvel with life span till 2115 faces extinction within 2040 if present ecological impingement continues unabated. • Immense tourism potential besides power generation remains to be harnessed.

  3. FACTORS ENDANGERING LIFE OF LAKE. • Colossal flow of the following from catchments: • Sediment & Silt. • Sewage. • Solid Waste. • Multiple pollutants. • Rise of lake bed level due to enormous deposit of above materials reducing volume of water holding capacity. • What causes such inflow into the lake: • Topographical location – valley; surrounded by hilly catchments. • Extensive ecological degradation including loss of forest cover in catchments made soil totally vulnerable to erosion & displacement. • Multiple network of streams originating & flowing through catchments discharge into Wah Umkhrah or Umshyrpi which join with Wah Roro & finally drain into the lake.

  4. What reveals the grim scenario! • Hydrographic survey • Water quality analysis • Situation analysis & assessment study of lake catchments. • Sediment flow rate data.

  5. Factors responsible for denigration of catchments: • Hilly terrain with deep gorges & ravines. • Extensive loss of forest cover rendering vast stretches into “open” land exposed to severe erosion leading to destabilization of soil profile & structure. • Population growth and human activities like deforestation; diverse land use pattern; faulty cultivation; lack of soil & water conservation; random mining & quarrying; unplanned development of road, buildings et al.

  6. Is the situation beyond salvage?Grim! But not yet if we act now. • Implement tangible remedial & preventive measures simultaneously. • Multi pronged approach both short & long term. • Administrative measures & enactment of relevant prohibitive Acts & invoking existing ones with diligence. • People’s participation through mass awareness & sensitization campaign.

  7. Interventions ~ • Holistic Action Plan for reclamation & rehabilitation of catchments: Massive afforestation programme – all other measures incidental & essential with depletion of this cover. • Extensive soil conservation measures with focus to check run-off & haphazard movement of water to the lake. • Stream management strategy to check silting of such seasonal / perennial drainage channels; reducing flooding & maintaining optimal capacity to canalize storm water. • Essence of rehabilitation need to be based on National River Conservation Plan & National Lake Conservation Plan. • Regulate inflow into Lake.

  8. A viable cyclic technology for treatment of sewage, effluent & other pollutants and regulating sediment, plastic, paper et al in waste water including tertiary treatment before transfer is allowed into the lake. • An alternative route for sewage transfer avoiding the lake. • Dredging & Excavation – most effective mechanism to remove huge silt and other contaminant deposit. • Plug possible seepage points evident in reservoir revealed from down stream discharge study. • Engineering structures as ancillary preventive measures. • Remedial measures primarily desiltation techniques like flushing, density current venting, sluicing et al is imperative.

  9. CYCLIC ACTIVATED SLUDGE TECHNOLOGY

  10. RESERVOIRS – Meant for ~ • FLOOD CONTROL • IRRIGATION • DRINKING WATER • HYDROPOWER • INDUSTRIAL Endangered by Sedimentation

  11. RESERVOIR SEDIMENTATION PROBLEM • STORAGE CAPACITY LOSS • DECREASE OF LIFE TIME

  12. SEDIMENTATION FACTORS • RESERVOIR SHAPE • SEDIMENT CHARACTERISTICS • RESERVOIR OPERATION • SEDIMENT/ RESERVOIR VOLUME RATIO • INFLOW CAPACITYRELATIONSHIP

  13. Reservoir Level DAM Streambed Delta formation Area Bottom Deposit Area Back Water Area DEPOSIT AREA

  14. Flood control space Conservation Storage Inactive Storage Dead Storage Outlet STAGE: II

  15. Flood control space Conservation Storage Inactive Storage Dead Storage Outlet STAGE: III

  16. Flood control space Conservation Storage Inactive Storage Dead Storage Outlet STAGE: IV

  17. STAGE: V Flood control space Conservation Storage Inactive Storage Dead Storage Outlet

  18. BACKWATER DEPOSIT CHARACTERISTICS • COARSE SAND & GRAVEL • UPSTREAM DEPOSIT ABOVE RESERVOIR LEVEL • DEPOSIT GROWS UPSTREAM & RESERVOIR • POSSIBLE EROSION DURING HIGH POOL WATER LEVEL

  19. BOTTOM DEPOSIT CHARACTERISTICS • SILT & CLAY • TRANSPORTED BEYOND DELTA • SEDIMENTATION CLOSE TO DAM • RESERVOIR TURBIDITY

  20. Flood control space Conservation Storage WATER & SEDIMENT Inactive Storage Dead Storage Outlet SLUICE OPEN – RAINY SEASON FLUSHING

  21. SEDIMENT DIVERSION BYPASS PIPELINE Outlet HYDROSUCTION BYPASSING

  22. DYKE CUM ROAD FOR MACHINERY AREA CLOSED BY DYKES & DRIED FOR EXCAVATION SEGMENTATION & DRY EXCAVATION

  23. DREDGING • Material • Process • Dredger types • Disposal

  24. . Thank You.

More Related