Construction of New Khanki Barrage

Khanki Barrage Pictorial View

Salient Features of Khnaki Headworks

Location Year of Const. Tot. Length/ Clear WW Des. Q
(cfs)
Off- take (lower chenab canal)
Water Allowance
(cfs/1000 acres)
CCA (ma) Des. Q (cfs) Length (Canal Miles)
Main Branch Distys. Total
Sixteen (16) Km
Down stream of Alexandra railway bridge, near WZD, Distt. GWA
1892 4,386/ 3,929 800000 2.84(P)
5.15(NP)
3.031
(Dsitt. Gujranwala Hafizabad, Shiekhpura, Nankana, Faisalabad, Jhang & T.T.Singh)
11,600 40 414 2,399 2,853

Khanki Headworks

Khanki headworks was constructed in the year 1892 and is one of the oldest weirs in the Subcontinent. The weir has deteriorated and outlived its life. A new barrage is, therefore, being constructed at a distance of 900 ft. from the existing weir on the downstream side.

An Overview

  • The weir was constructed during 1889- 1892
  • It was the first weir in Punjab founded on alluvial sandy bed of river
  • It was designed and constructed under conditions of extreme economy
  • The weir got repeatedly damaged in portions and had to be remodeled extensively during 1919- 1920 and 1933- 1935
  • The weir originally was a shuttered type weir comprising 8 spans of 500 ft each, left undersluices (12 No. 20 ft each) and canal head regulator (12 spans of 24.5 ft each)
  • With the extensive remodeling during 1933- 35, the weir now comprises (left to right):
    • Left Undersluises (12 No. 20 ft. each)
    • Three weir bays (1423 ft)
    • Central undersluices (18 No. 20 ft each)
    • Three weir bays (1545.75 ft)
    • Right Undersluices (18 No. 20 ft each)
  • Total width between abutments                              4386’
  • Waterway                                                           3928.75’

Discharges Exceeding 800,000 Cusecs (1922- 2010)

Sr. # Date Discharge (Cfs) HFL
1 20-09-1950 1,011,000 738.50
2 26-09-1954 806,000 736.80
3 27-08-1957 1,086,000 739.00
4 06-07-1959 1,021,000 738.70
5 10-08-1973 846,000 740.00
6 26-09-1988 864,000 739.30
7 10-09-1992 910,000 738.00
8 24-08-1996 851,000 738.50
9 28-08-1997 847,000 738.20

Results of Hydrological Analysis

RETURN PERIOD PROBABLE Q (cfs)
2.33 386,300
10 705,400
50 1,020,700
100 1,153,800
200 1,286,500

Safety Evaluation Study of Khanki Head Works

  • study carried out by M/S EGC in 1998 concluded that:
    • Crest of weir bays be lowered by 5.0 feet;
    • Existing weir bays be divided into smaller bays of about 60 ft provided with vertical or radial gates;
    • New pressure pipes (vibrating wire type) be installed;
    • AR bridge across the structure be provided; and
    • Feasibility study be conducted to determine whether the weir be remodeled or replaced.

Feasibility Study & Detailed Design (JV of M/S NDC & NESPAK 2003-2008)

  • Replacement of existing headworks  with a new barrage 900 feet downstream is proposed on the following basis:                
    • Severe aging effect;
    • Capacity constraint;
    • Lack of effective control on river regulation;
    • Inefficient and insufficient physical communication between the two banks;
    • Mixture of several out dated design & construction techniques;
    • Dangerous dismantling & rebuilding operation if existing structure remodeled;
    • Gates installation impossible in existing weir; and
    • Inadequacy of existing weir for automation.

Analyses & Outcome of Remodeling Option
Capacity constraint
Exiting design discharge of  headworks                                                  =    800,000 cfs;
Design discharge based on 100 years return period                          = 1,100,000 cfs;

      • Will require extension of existing weir (28 bays each 60 ft ), causing excessive shoaling upstream of the headworks
      • Will have no bridge 
Structural components
Sheet piles
      • Inadequate depth
Stilling basin
      • Inefficient energy dissipation;
      • Hydraulic jump sweeps out at design discharge; and
      • Deficient thickness.

Recommendations by Special Committee on Khanki Headworks A special committee was constituted on October 09, 2008 regarding recommendations for optimal implementation of project.
Options discussed:

    • Option 1:- Continue with existing headworks while carrying out routine annual operation and maintenance activities with a hope of extending the useful life of the old structure for another half a century or so;                    
    • Option 2:- Rehabilitate the existing structure through repairs and remodeling some of the deficient components;
    • Option 3:- Replacement of Khanki headworks with a new barrage.
The committee recommended option-3 ; construction of a new barrage replacing the existing Khanki headworks considering it most appropriate and beneficial proposal for implementation.

Recommended Project

  • A new modern barrage, 900 ft downstream of existing weir and incorporating an AR Bridge
  • New head regulator of L.C.C;
  • Re-aligned head reach of L.C.C originating from new head regulator and joining existing LCC at RD 5
  • Improvement of roads on both  river banks, buildings and other infrastructure.
  • Rehabilitation of River Training works

Salient Features of the Project

  • Main weir                                                                                            55 bays @ 60 ft. each
  • Undersluices                                                                                      10 bays @ 60 ft. each
  • Silt excluder in first two bays of left undersluice               8 tunnels
  • LCC head regulator                                                                          6 bays @ 30 ft. each
  • Bridge on main barrage                                                                 4384 ft.
  • Bridge on head regulator                                                              215 ft.
  • Radial gates for barrage                                                                65 Nos (60 ft wide each)
  • Radial gates for LCC head regulator                                         6 Nos (30 ft wide each)
  • Two fish ladders (left and right)                                                 215 ft.
  • Two divide walls (left and right)                                                 342 ft.
  • Two guide banks (left and right)                                               1737 ft.
  • Instrumentation                                                                                              
    • Vibrating wire electronic piezometers                    96 Nos.
    • Stand pipe piezometers                                                  12 Nos.
  • New canal link for connection with existing L.C.C            5000 ft.
  • Improvement of existing approach roads                           35 Km
  • Sloping studs on left side downstream of new barrage   04 Nos.

Project PC-I Cost Summary

Sr ITEM COST
(in Rs M)
1 Civil Works           13,184
2 Mechanical & Electrical Works             3,729
3 Sub-Total           16,913
4 i)  Project Management Office Cost                 203
ii) Consultancy services (Supervision + Individual)                 669
Sub Total                 872
5 Base Cost (3+4 )           17,785
6 Escalation @ 6.5% on local cost and 3% on foreign cost                 948
7 Physical contingency @ 5% on the base cost & escalation                 887
8 Taxes and duties @ 12.5% on foreign cost                 447
9 Total  (6+7+8+9)           20,067
10 IDC @ 9.23% on local cost and 2.5% on foreign cost             3,375
11 Total (9+10)           23,442

Project Benefits

  • Sustainable irrigation supplies to about three million acres of fertile land in seven districts of Punjab;
  • Ensured safe  passage of floods due to enhancement in design capacity of the new barrage; and
  • Provision of communication link across the river.

Environmental Impacts

  • Project Category “B”.
  • No resettlement or rehabilitation involved.
  • No change in the hydraulic capabilities and no significant changes can be anticipated in physical, environmental, biological or social conditions.
  • No new withdrawals.
  • The canal will be run to its designed authorized capacity.
  • Physical, biotic and social impacts if any at all shall be mild and reversible.

Time Line for Implementation

Sr. # Activity Target Date
1 PC-1 approved by ECNEC September 03, 2009
2 Procurement of supervision consultants June 30, 2012
3 Award of Contracts
Preliminary works for New Khanki Barrage Project ICB/NKB-01
Construction of New Khanki Barrage Project & Auxiliary Works NCB/ICB-01

Nov 20, 2011
Jan 31, 2012
4 Completion of the works
Preliminary works for New Khanki Barrage Project ICB/NCB-01
Construction of New Khanki Barrage Project & Auxiliary Works NCB/ICB-01

May 20, 2013
Feb 28, 2016
5 End of DLP
Preliminary works for New Khanki Barrage Project ICB/NCB-01
MConstruction of New Khanki Barrage Project & Auxiliary Works NCB/ICB-01

May 20, 2014
Feb 28, 2017

Financial and Physical Progress

Approved Cost Total Expenditure upto June, 2012 2012-13 Total Cumulative Expenditure to date Financial Progress to date
(%)
Physical Progress to date
(%)
Allocation Expenditure
23,442 - 1,000.00 1,883.386 1,883.386 8.03 Contractor Mobilized

Disbursement Projection

Currency Net Commitments Disbursement till June, 2012 Disbursement till June, 2013 Actual Disbursement till date Projection FY 2013-14 Projection FY 2014-15 Projection FY 2015-16
US$ (Million) 270.000 - 17.788 17.788 78.125 108.387 65.70
Page updated on July 25, 2013