Stratagems

Major, Medium and Minor Irrigation schemes

Irrigation department, Kerala is the agency that investigates, designs, constructs, operates and maintains Minor, Medium and Major Irrigation projects/schemes.  As per the classification followed by the department, schemes having a cultivable command area upto 2000ha are treated as minor irrigation works. Medium irrigation works are those with irrigable command area of more than 2000 ha, but less than 10,000 ha. Those schemes above 10,000 ha are classified as Major irrigation schemes.

Major and medium irrigation schemes
The department develops and maintains major and medium irrigation schemes/projects across the state. The primary activity of the Department is providing irrigation facility to the farmers of the State through its system comprising reservoirs, main canals, branch canals, feeder canals and other related infrastructure. The department maintains water distribution through the canal system. Water distribution is being carried out based on the cropping pattern of a particular area and a water distribution calendar prepared and approved by a committee headed by the District Collector with members of farming community, other stake holders and department officials. For proper distribution and maintenance of the canals Water Users Association (WUA)/ Farmers Association plays an important role.

Minor Irrigation schemes
Minor Irrigation schemes are divided into Class-I and Class-II depending on the ayacut served. Schemes serving above 50Ha up to 2000Ha are classified as MI Class-I. Lift irrigation schemes are also Minor irrigation schemes serving at least 40Ha.
 
MI Class-I  schemes
Minor works like improvements to tanks and rivulet, construction of check dams, sluices, regulators, bunds, vented crossbars, salt water barriers, layout of channels and drainage structures etc are usually undertaken under MI Class-I schemes.

MI Class-II Schemes
Minor irrigation works including construction of vented cross bars, canals, improvements to natural drains etc are taken up under this scheme.

Lift Irrigation Schemes
Lifting of water is required for irrigating fertile land at a higher elevation where gravity flow of stored water is not possible. Although mechanical lifting is required, these schemes are very useful and serve the marginal farmers of the State.  


(a typical lift irrigation scheme and the paddy field benefited by the scheme) 

Renovation of ponds and tanks
Ponds and tanks are the local source of water in many villages of the state. Kerala acquire 18681 number of ponds. Irrigation department has been taking up renovation of ponds and water bodies in Kerala through de silting, repairing of sluices and constructing retaining structures its inlet and outlet arrangements

     
Ayyankulam in Palakkad district after renovation works


Ponds in Ernakulam district after renovation

Flood Management

Flood control is a major activity under irrigation department due to the peculiar terrain of the State. The main works for flood control include flood bunds on the banks of the major rivers to bring the flood waters within the river regime thereby reducing to destruction to life and property.  

Strengthening of river sides by retaining walls is highly essential in Kerala’s topographical condition.  All the rivers flow through narrow  gorges  and the average heights of the sides of rivers is about 6 to 12m in the midlands and coastal regions.  The top soil in these regions are lateritic and the bottom layer is a mixture of laterite sand and clay.  During the monsoon months due to the high velocity and undercurrents, the sides of rivers in the bottom depths to a height of  about 1.5m gets washed off due to the sandy nature and in the subsequent monsoon, the top soil collapses.  Therefore, protection water by different methods is essential in the bottom layer. River training works, construction of flood banks etc are works taken up under flood management programme.

Coastal Zone Management

The State of Kerala with its very high density of population has the maximum concentration of population in coastal zone. The coastline of Kerala is subjected to severe erosion in a major portion of its length during the monsoon seasons, when the sea becomes rough due to consistent attack of waves. Erosion is very severe in the coastal areas during the southwest monsoon period. During the monsoon seasons, the high waves cause overflow and flooding of the low lying backshore lands all along the coast, resulting in considerable loss of life and property. Kerala has taken up coastal protection works from the early sixties using the design developed by U.S Corps of Engineers. Later, a new design proposed by CWPRS, Pune was adopted. Latest design of seawall is from IIT, Madras.

Out of the total 560Km of coastal line of Kerala, the length which is vulnerable to erosion and which requires protection is 478Km as assessed by the Directorate of Central Water Commission and Coastal Erosion Studies, Kerala State. The present scenario is that a total of 354.29 Km of seawall has been newly constructed so far using State funds and Central Funds. The balance length of new seawall to be constructed is around 123.71Km.

A view of the strengthened Seawall at Panathurakkara, Poonthura, Thiruvananthapuram
(a) Near to Subramonya Swamy Temple                      (b) to the North of Mosque

(c) & (d) Groyne constructed perpendicular to the shore

Inland Water Ways

The state of Kerala, with numerous backwaters, is one of the States in India, where waterways can be successfully used for commercial Inland water transport. Inland Navigation was the principal mode of transportation in the region till the middle of twentieth century. With the modern fast moving road and rail transportation system the navigation route and Canal system remained ignored for the past fifty years.

Present Scenario

The West Coast Canal  can be broadly divided into four sections as below.

1.

Kollam – Kovalam

74.18Km.

2.

Kollam-Kottapuram( NW III)

168 Km.

3.

Kottapuram -Vadakara

207.90 Km.

4

Vadakara- Neeleswaram

140.45 Km

 

Total

590.53 Km

 

Government of Kerala has undertaken the improvements of West - Coast Canal to make it fully navigable as per State Waterway standards. Out of the total length of 590 km of West Coast Canal, only 299 km is presently navigable, which includes 168 km of National Water Way III. On completion of the ongoing works, another 82 km will become navigable. In order to achieve the target, remaining 209 km also will have to be made navigable. Once the entire length becomes navigable, it has to be converted into National Waterway standards, by providing all infrastructural facilities such as terminals, boat jetties, navigational aid, warehouses etc. The present status of different sections of the Inland Waterways  in the state is as stated below.

I.                    Kovalam – Kollam

Total Length

74.18 km

Natural canal

19.775 km

Artifical canal

54.405 km

Navigable Length

31 Km

Length for which works are arranged

16 km

Balance length to be taken up

27 km


This route is having a length of 74.18 km from Kovalam to Kollam, which consists of back waters like Akkulam, Kadinamkulam,Anjengo,Nadayara,Paravoor and Ashtamudikayal and artificial canal like ParvathyPuthanar and Kollam thodu with historic tunnels at Varkala in between.  The stretch has to be dredged out and protected.

II. Kollam-Kottappuram National WaterWay III

 As part of a program for developing waterways by the Central Government, length of 168 Km. of Waterway from Kollam to Kottapuram of West Coast Canal including Udyogmandal and Champakara Canals was declared as National Waterway No.III with effect from 1993. The work in National Waterway No.III are being done by Inland Waterways Authority of India (IWAI), Government of India. The canals coming under National Waterway III are as follows.

 

Sl No

Route

Distance

1

Kollam- Kottappuram   NW III

168Km

2

Udyogmandal (feeder canal) NW III

23 Km

3

Champakara(feeder canal) NW III

14 Km.

Total

205 Km

 

 

                                                           The above stretch is fully  navigable.

III  Kottappuram – Vadakara

Total Length

207.90 km

Natural canal

103.873 km

Artifical canal

104.023 km

Navigable Length

77 km

Length for which works are arranged

16 km

Balance length to be taken up

115 km

 

This reach is widely known as Canoli Canal which is the General nomencalture of all artificial canal between Kottappuram and Vadakara having a length of 208 km from Kottappuram to Vadakara, we have natural rivers like Kadalundi ,Poorapuzha, ThirurPuzha, VadakkumpadduPuzha, Chaliyar, KallaiPuzha, Korapuzha, Akalapuzha and Kuttadi river and artificial canals like PC canal, TK canal, Canoli canal, BK canal, EK canal and Payyoli Canal. Certain development works like dredging and side protection have been carried out by the Irrigation Department based on the availability  of funds.  Though natural rivers have navigable length of 103km at different stretches, waterway do not have State Waterway standards.

IV  Vadakara – Kottappuram (Neeleswaram)

Total Length

140.45 km

Missing links

42.41 km

Navigable Length

65 Km

Length for which works are arranged

45km

Balance length to be taken up

 31km

 

This route is having a length of 140.45 km from Vadakara to Kottappuram (Neeleswaram). In between Vadakara and Valapattanam there are 4 missing links in this waterway; where there are no canals exist. Out of this missing link, formation of Badagara to Mahe canal for a length of 17.61km the work is in progress. In Mahe – Valapattanam stretch of canal with a length of 58.51 Km, there are three uncut portions having a total length of 24.8 km. For taking up works in these reaches investigation has been completed. The reaches north of Valappattanamup to Kotti and Kotti to Neeleswaram (Kottappuram) of Kasargod is presently navigable as per State waterway standards. Certain minor works like dredging at certain portion is required. Mission of the department is to make the entire stretch of West Coast Canal navigable.

Salt Exclusion works
One of the important problems faced by the State is salinity intrusion. Lowering of the river beds due to unchecked sand mining has accelerated this problem. Now, salinity is being experienced up to 30Km into the upstream length of rivers from the sea mouth.

Department has started addressing this problem by the construction of regulators to check salinity intrusion. This problem is a threat to many drinking water schemes and irrigation schemes in the State.


(Velliyamkallu Regulator cum Bridge constructed across Bharathapuzha in Ottappalam Taluk of Palakkad District to prevent salinity intrusion)
 

Interstate water sharing
Kerala has 3 East flowing rivers that originate from the State and flow through the neighbouring States. We also share water from Irrigation projects with neighbouring states. An Interstate wing functions in the Irrigation Design & Research Board, Thiruvannathapuram.  The Chief Engineer, ISW is in charge of this Interstate wing of IDRB. Under the Chief Engineer , Joint Director ( Dam Safety and ISW ) with two Deputy Directors and six Asst. Directors deals with all works related to Interstate waters. There are disputes which are under the consideration of the courts. These are continuously monitored and acted upon by the Department to protect the interests of the State.

The Inter State Water Wing deals with the Interstate water sharing aspects / cases in various courts and all other allied matters  of Parambikulam Aliyar Project System (a group of 9 dams and 2 weirs); Mullaperiyar Dam; Pamba Achenkovil Vaippar link project; Siruvani Drinking Water Supply project; Walayar Irrigation Project;  Kanyamadagu Dam;  Chittar Pattanamkal project ;  Neyyar Irrigation Project ;  Cauvery Water Dispute and  Unauthorized diversion of the state water resources by other states.
There are three Inter State Agreements  viz the Periyar Lease Deed (executed between the erstwhile Maharaja of Travancore and the Government of Madras on 29.10.1886) Parambikulam - Aliyar Project Agreement (between the states of Tamil Nadu and Kerala executed on 29.05.1970  with retrospective effect from 09.11.1958) and the Siruvani  Drinking Water Supply Agreement( made between Kerala and Tamil Nadu on 19.08.1973).


A view of the Parambikulam reservoir

The Chief Engineer ISW holds Chairmanship of Joint Water Regulation Board in alternate water years, which is responsible for the proper regulation of waters collected and distributed through the Parambikulam Aliyar Project System in accordance with Parambikulam Aliyar Project Agreement. Chief Engineer ISW is the Member Secretary and Convenor of Parambikulam Aliyar Sub Committee of National Committee on Dam Safety and Member of the Technical Committee of National Water Development Agency. Chief Engineer ISW is also a member of the Joint Control Board of Siruvani Drinking Water Supply project. Joint Control Board is responsible for proper regulation of supply of water from the project and measurement of quantity diverted.

Investigation for new schemes & Design of structures

Investigation for new schemes and design of structures are carried out in Irrigation Design and Research Board (IDRB) which is the Central Design and Research Organization of the Department with Head quarters at Thiruvananthapuram. IDRB deals with Design of Irrigation structures, Investigation and preparation of DPR of major and medium irrigation project ,works related to dam safety , collection and assimilation  of hydrological data  imparting  technical training to officers  etc . Conducting periodical inspection of dams and recommending suitable rectification works, preparation of inundation maps, dam break study, and hydrological review of dams are also dealt with by Chief Engineer(IDRB). Issuing Administrative Sanction, Technical Sanction and Financial Sanction for the works under Kerala Engineering Research Institute, Coordinating activities of Field Studies Circle and Coastal Engineering Field Studies, scrutiny of estimate for investigation of all projects under the Department are also attended in this office. The only irrigation project coming under the Board is the Peechi Irrigation Project.

The board consists of a design wing, research wing and an investigation wing. Design of all structures related to water resources including dams, canals, vented cross bars, lift irrigation schemes, check dams, regulators, navigation locks and other retaining structures are taken up in the design wing. Kerala Engineering Research Institute (KERI), Peechi is a sub unit of IDRB engaged in Research activities and quality control. Field Studies Circle (FSC), Thrissur is another sub unit engaged in hydrological and meteorological collection of data and coastal zone management. The important functions of the Kerala Engineering Research Institute include conducting sedimentation studies of major dams using Integrated Bathymetric system, conducting model studies of hydraulic structures, field investigation for foundations, mix design, testing of materials etc. The quality of engineering works in the Department is ensured by the Quality Control wing of KERI. The Coastal Engineering Field Studies also function as a division under KERI, which undertakes the task of collecting coastal data along the Kerala coast.

Command Area Development and Water Management


CADWM deals with development of the command area of completed major and medium irrigation schemes. The main objective of CAD Programme is to increase the utilization of created potential by better water management and distribution techniques and thereby achieving higher production and thus increasing the income of individual farmers. By construction of field channels and by adopting proper water management methods for distribution of water the wastage of water has been considerably reduced. The ayacut area where water was not reaching previously are now getting sufficient water. Adaptive trials, demonstrations, training to farmers etc play a key role in better water management and Agricultural practices. As a result, the Agricultural production has gone up. The land utilization and utilization of the created irrigation potential is also increased.

Engineering activities such as Construction of field channel, filed drain, reclamation works, correction of system deficiencies within the command area are being carried out in the CAD programme.

Kuttanad package

Based on the request of the Government of Kerala to address the perennial problem faced in Kuttanad, the Union Government entrusted the Dr. M S Swaminathan Foundation, Chennai to conduct a scientific study of Kuttanad region and suggest suitable measurers to mitigate agrarian distress in Kuttanad. The MSSRF recommended a variety of interventions to be implemented as a Package with a total cost of Rs. 1,840 Cr. which was accepted by the Union Government for funding under ongoing central sector schemes.

To mitigate the agrarian distress in Alappuzha and Kuttanad Wet Land Eco System MSSR foundation recommended measures to strengthen the ecological security of the area, which includes salinity and flood management of Kuttanad wet land system and to provide infrastructure support to paddy cultivation, which includes construction and strengthening of outer bunds. Out of the 15 task recommended by MSSR Foundation, the following are taken by the Irrigation Department under the Chief Engineer Kuttanad Package Alappuzha.

(1)    Measures for salinity control and flood management in Kuttanad.

  • Modernisation of Thannermukkom Bund to manage salinity and minimize  Ecological decay
  • Improving the efficiency of the Thottapally Spill Way and leading channel
  • Regulation of flood water in Kayal area near C&D and Rani Chithira Blocks
  • Complete construction of the AC canal with removal of all blocks.

(2)    Provide infrastructure support to paddy cultivation

  • Need for restoration of KWS, Onattukara and Thuravoor- Pattanakadu rivers, Canals, drains and water bodies like ponds
  • Orumuttus -  Creation of 33 permanent orumuttus at Kottachira across Kariyar

Mechanical Works
Mechanical wing deals with design, fabrication, erection & repair of mechanical structures. The wing handles the upkeep, operation and maintenance of departmental dredgers. The issuance of essentiality/economy certificate and fixing upset value of vehicles, plant & machinery for the department is undertaken by the mechanical wing. Maintaining the required draft for water transport and hire charges of plant & machinery for construction works are also carried out by this wing.