Quality control of Sardar Sarovar Project (SSP) Canal Works
Sardar Sarovar Project (SSP) is a multi purpose Rivervelly Project, currently under, construction across the river Narmada to Irrigate 17.92 lakh hectares annually in the state of Gujarat. The main dam has reached upto spillway crest level i.e. 121.92 meter. Raising of piers, construction of bridge and installation of spillway gates remain to be taken up after obtaining clearance from the Narmada Control Authority. Both the hydropower stations are fully operational with installed capacity of 1450 MW. The Narmada Main Canal, the largest lined Irrigation Canal in the world has been completed in 458 Km length with 634 structures and water has been flowing right upto Gujarat-Rajasthan border since March, 2008. Out of 38 branch canals, works of 30 branch canals are completed and works of remaining branch canals are under progress. Works of distributories and minors in North Gujarat, Saurashtra and Kachchh are under progress. In all, works of Rs.6300 Crores are under progress through 154 contracts and these works are presently going on at about 600 different locations.
Quality Control Organisation :
The entire work of SSP can be broadly divided into three main works:
(a) Dam works (b) Hydro Power (River Bed & Canal Head) (c) Canal Systems.
Quality Control Organization for the Canal Works has been recently restructured and a decentralized approach has been adopted where in a Quality Control Division Office is made functional under each field Chief Engineer and one or more Quality Control Sub Division Offices are made functional under field Superintending Engineer depending on their workload thus 7 field Chief Engineers and 16 Superintending Engineers are fully responsible for construction as well as Quality of works under their jurisdiction. Day to day quality control supervision, sampling, testing etc. will be the responsibility of 23 Nos. of Quality Control Sub Divisions. Moreover the field Chief Engineer will be directing the Q.C. Divisions working under them for effective Quality Control.
In addition to the above stated decentralized arrangement, a centralized system for Quality Control and Vigilance is also functional under the Chief Engineer. (Quality Control) For this purpose, two Quality Control Circles headed by Superintending Engineers have been sanctioned and working. One such Quality Control Circle is working at Gandhinagar looking after the Canal Works of Phase I, Phase II, and Saurashtra Region and another at Ahmedabad to look after the canal works of NMC beyond Ch. 263 Km, North Gujarat and Kutch region. Under each of these two Quality Control Circles, two nos. of flying squad headed by Executive Engineers have been sanctioned to carry out Quality auditing of ongoing works on a random basis. The organization chart of Quality Control staff under Quality Control Chief Engineer is enclosed Annexure-1. For above referred two Quality Control Circles, jurisdictions of works are shown in enclosed Annexure-2. For Vigilance cases and Inquiry matters, an Inquiry Cell is operational in Nigam Head Office, which is headed by one Executive Engineer. This inquiry Unit is also carrying out preliminary inquiry for the various cases referred by Nigam Vigilance Branch or by Government as a special case and submit preliminary inquiry reports.
Field Quality Control :
The entire construction works of canal system are being executed by various Chief Engineers (Construction) with the help of construction Division and Quality / Laboratory Division and Sub Divisions working under Superintending Engineers. The Quality / Laboratory Sub division has to assure that the entire work is of required quality by testing all construction materials / product and they help construction divisions in solving quality problems which arises during the execution of works.
For carrying out day to day testing works of construction material / product, the field laboratories have been established at suitable location in the vicinity of works under progress. These field laboratories are carrying out routine field test and transmit the test results to the construction sub divisions / divisions for taking further action. Out of these field laboratories, certain laboratories are also established at suitable headquarter for special tests with all required testing equipments.
Further more in tenders of SSP canals, we have introduced a "Quality Assurance" Clause ( Annexure -3) also in which Contractor has to assure about the quality of construction material / final product. The contractors have to develop their own testing laboratories also under this clause and they also submit to Nigam the test results of the construction material / final product. The suitable actions as per tender specifications are being taken on the receipt of test results, from contractors.
For carrying out quality control works and testing works smoothly, the Chief Engineer (Quality Control), has issued following manuals which elaborately describe the procedure for carrying out quality control works (Checklist / O.K. Cards etc.) as well as details of tests to be carried out for construction material and final product.
- Guidelines for Quality Assurance & Quality Control for the various canal works.
- Guidelines for Quality Assurance & Quality Control for Road works.
- Guidelines for Quality Assurance & Quality Control for gate works.
- Compendium of various tests for construction material.
- Formats for forms and registers to be maintained for Quality Control Work.
Expert committee on cement and concrete (ECCC):
The Government of Gujarat, Narmada Development Department, Gandhinagar vide its resolution No. NMD/1887/4056/47/H dated 19.10. 1987 constituted an "Expert Committee on Cement and Concrete (ECCC)" for Sardar Sarovar Project to review and evaluate the factors regarding cement and its usage. In consultation with ECCC, Nigam has identified 17 cement plants from which cement is being used in SSP works. The list of these cement plant is kept at Annexure - 4.
Committtee for identification of reinforcement steel:
As a result of discussion with the ECCC & Board of Consultant, it was decided to use CRS bars in the construction of canals / structures where saline area (sub soil / Sub Soil water) is encountered. Accordingly SSNNL has constituted a committee vide its circular No. SBC/1198/1/N dated 30.05.1998 for the identification of manufacturer of CRS bars. This committee at present is engaged in ensuring that production by manufacturers is as per required Quality Standards and within permissible variability in respect of mechanical, chemical and corrosion properties as prescribed in relevant codes. The Committee recognizes the steel plants for pre qualification / selection of vendors which can produce the reinforced bars to satisfy technical requirements.
List of the Steel plant identified by SSNNL is shown in Annexure - 5.
Third Party Inspection (TPI) for SSP works :
SSNNL has engaged Third Party Inspection (TPI) agencies for some canal works and several structures. The list of works entrusted to TPI is shown in Annexure - 6.
Recognisation of testing laboratories :
Generally the testing is got done in Government laboratories / Government institutions Labs.
1.0 ASSURANCE PROGRAMME:
In addition to the testing procedure as laid down in clause No. ____ (T.C. 23 of Model tender related to testing of Material) of the tender document the contractor shall submit a detailed field Quality Assurance Programme containing the overall quality management and procedures which he proposes to follow during various phases of construction as detailed in the relevant clause of the technical specifications of the contract and get it approved from Engineer-in-Charge within 30 days after the letter of intent is issued or before the date of work order whichever is earlier. This shall include arrangement of testing apparatus / instrument covering the requirement of items envisaged in the contract and details of the testing programme. The document of quality Assurance programme shall generally cover but no limited to the following.
- Contractor’s organizational structure for the management and implementation of the quality assurance programme.
- Source of various materials
- Inspection and test procedure both for material and their product and field activities.
- System of handling storage and delivery of materials.
- System of preparation and maintenance of test records.
The Quality Assurance Programme shall also include the programme proposed to be followed by his sub contractors in case the contract agreement allows him to engage sub contractor.
2.0 TESTING OF MATERIAL:
All materials, before brining to the site of work shall be inspected and tested by the contractor. For testing, the contractor may set up his own laboratory at his own cost. For Place (laboratory) of testing should be got approved from Engineer-in-Charge. Test results shall be furnished by the contractor to the Engineer-in-Charge. The cost of all such testing shall be borne by contractor.
After materials are brought to site if necessary, Engineer-in-Charge or his subordinate shall test in accordance with relevant clauses of the contract, if necessary. In case of discrepancy in the SSNNL’s and contractors result the SSNNL’s result shall be final and binding to the contractor.
Materials whose test result does not conform to the standard and is not acceptable to the Engineer-in-Charge shall be rejected and removed from the site.
3.0 TESTING PROCEDURE:
The contractor shall carry out all sampling and testing in accordance with the relevant Indian Standard and / or International Standard or as stipulated in the contract, where no specific testing procedure is mentioned the test shall be carried out as per the prevalent accepted engineering practice and direction of Engineer-in-Charge.
The frequency of sampling and testing of all materials and products of construction shall be as mentioned in the technical specifications, or as per SSNNL “Manual for Quality Assurance and Quality Control” and relevant and recent BIS/ASTM/ASME/BS practice. In case of discrepancy in the standards, the decisions of the Engineer-in-Charge will be final. In case due to changes in the codal provisions during course of execution if the acceptance criteria of the test gets changed, the contractor shall have to follow the revised criteria of acceptance. The contractor shall not claim for any compensation as a result of rejection of his material or product of construction due to inferior quality on account of such changes. The testing frequencies set forth in different technical specification are the desirable minimum, and the Engineer-in-Charge shall have a full authority to revise it as he finds necessary to satisfy himself that the quality of materials and works together comply with appropriate specifications requirements.