Idamalayar Major Irrigation Project JI02689
|1||Irrigation Project Name||Idamalayar Major Irrigation Project|
|2||Irrigation Project Name Alias|
|9||Basin||West flowing rivers from Tadri to Kanyakumari|
|14||Work Started in 5 Year Plan||VI-Plan|
|15||Completed in 5 Year Plan|
|16||Project Approval Status||Planning Commission|
|17||Year of Approval by Planning Commission||1994|
|18||Approved Cost (Rs. in cr)||107|
|19||Actual Cost (Rs. in cr)|
|20||Culturable Command Area (CCA) (th ha)||14.39|
|21||Ultimate Irrigation Potential (UIP) (th ha)||27.51|
|22||Potential Created (PC) (th ha)|
|23||Project Covered under ERM Scheme||No|
|24||Project Covered under CADA Scheme||No|
|25||Project Covered under AIBP Scheme||No|
|27||Project Covered under Tribal Sub-Plan||No|
|28||Project Covered under Drought Prone Area Programme (DPAP)|
|1||Bhoothathankettu /Periyar Barrage||Barrage/ Weir/ Anicut (BWA)|
|2||Thumburmuzhi /Chalakudy Diversion Weir||Barrage/ Weir/ Anicut (BWA)|
The Idamalayar Irrigation Project (IIP) is a diversion scheme for diverting waters of Periyar River for irrigating vast cultivable lands in Periyar and Chalakudy basins. The proposal envisages construction of a main canal taking off from the right flank of the existing Bhoothathankettu barrage on Periyar river, a canal system called low level canal system (LLC) drawing water from the main canal for irrigating areas on the right bank of Periyar river and a link canal, also drawing water from the main canal for augmenting flow in the canal system of the existing Chalakudy River Diversion Scheme (CRDS) for irrigating additional areas in the Chalakudy basin.
The length of main canal of IIP is reported as 32.278 km as per new alignment after forest land for canal was handed over by the forest department. The main canal has a direct ayacut of 999 ha. The low level canal and link canal take off from the terminal point of the main canal. The low level canal has a length of 27.30 km and the link canal has a length of 7.58 km. The LLC serve an ayacut of 4,672 hectare. The water diverted through the link canal to the Chalakudy system would be used to irrigate the areas on the left bank of Chalakudy river which are at present served by waters of Chalakudy river through the LBC of CRDS. The water thus spared from the LBC system of CRDS would be used in the RBC system of CRDS for irrigating additional ayacut on the right bank of Chalakudy river to an extent of 8,514 ha. Thus, total additional ayacut that would be served by the IIP is 14,394 ha lying in Periyar and Chalakudy basins (Ernakulam and Thrissur districts).
Ayacut details are as given below:
|Main canal||999 ha|
|Low level canal||4,672 ha|
|Right bank canal Chalakudy||8,514 ha|
|Left bank canal of Chalakudy||209 ha|
The existing Bhoothathankettu barrage on Periyar was completed in 1967 under the Periyar Valley Irrigation Project (PVIP). The total catchment area of Periyar at the barrage is 3,048 sq km with a free catchment area of 757 sq km The completed PVIP provides irrigation to a command area of 32,800 ha on the left bank of Periyar river, besides providing domestic water supply to Cochin and industrial water supply to FACT. The IIP proposes to exploit the excess water of Periyar at Bhoothathankettu barrage after meeting the committed requirements of PVIP.
The existing Chalakudy River Diversion Scheme diverts waters of Chalakudy river at Thumburmuzhi weir through the left bank and right bank canal systems. The weir was completed in 1957. The ayacut served by the project through its 34 branch canals under LBC and 29 branch canals under RBC is 14,142 ha.
Main Components of the Project
- A main canal 32.278 km long, taking off from the right flank of the existing Bhoothathankettu barrage with a head regulator at the take off point serving a direct ayacut of 999 ha.
- A 27.30 km long low level canal branching from the terminal point of the main canal with its branches and distributaries to serve an ayacut of 4,672 ha.
- A 7.58 km long link canal connecting the terminal point of main canal with LBC of CRDS at Ch. 10.20 km for conveying water from Periyar to Chalakudy system.
- Remodelling works of existing CRDS comprising (a) remodelling of Chalakudy Left Bank Canal to command additional 209 ha, (b) remodelling and extending the Chalakudy Right Bank Canal for conveying the increased discharge to irrigate an additional 8514 ha and (c) raising the height of the weir at Thumboormuzhi across Chalakudy river by 30 cm to provide necessary head for the additional command.
- Beautification of Malayatoor lake (Manappattuchira).
- Renovation works of the existing LBC and RBC systems of CRD Scheme in order to stabilise the irrigation in the existing ayacut of Chalakudy system.
Techno Economic Appraisal
The project was approved by TACTechnical Advisory Committee in its 58th meeting held on 24/06/1994 subject to some conditions for an estimated cost of Rs 107 crore (Price level 1992) with GCA as 14394 hectare, CCA as 13209 hectare and annual irrigation as 27513 hectare to irrigate in the district Ernakulam, Idukki and Trichur (Thrisuur). The project did not receive Planning Commission approval. The project was started in the year 1981 and so far no irrigation potentail has been created.The latest estimated cost of the project is Rs 740 crore (2010 price level) and expenditure upto September 2011 is Rs 352.70 crore.