Islam Barrage, located about six miles north-west of Hasilpur town, was constructed across River Sutlej during 1922-1927 as a component of Sutlej Valley Project for feeding Bahawal Canal (5,400 cusecs) and Qaim Canal (558 cusecs) on the left bank and Mailsi Canal (4,883 cusecs) on the right bank.
It was designed for a maximum discharge of 300,000 cusecs. After the implementation of Indus Water Treaty, the head regulator of Mailsi Canal at Islam Barrage was abandoned and the canal started receiving supplies from the new Sidhnai-Mailsi Link Canal constructed in 1965. Similarly the capacity of Bahawal Canal was reduced to 1,000 cusecs by shifting lower areas of the canal on to the new Mailsi-Bahawal link.
Necessity of Rehabilitation
The main structure of the Islam Barrage, constructed in 1922-27, is now nearly 80 years old. The barrage is a low crested gated weir having a stated designed discharge capacity of 300,000 cusecs. Originally the main weir had 16 bays each 60 feet wide flanked by right and left undersluices each consisting of 4 bays also 60 feet wide each. However, after the damage caused by 1929 flood, when six of its central bays (No. 11 to 16) collapsed, the configuration of the barrage was substantially changed in 1929-30 by replacing 6 collapsed bays of 60 feet width with 11 bays of reduced width of 29 feet each. In 1953, a subsidiary weir was constructed downstream side of the main barrage structure to check and control excessive retrogression that was occurring downstream of the main structure.
The barrage, the subsidiary weir and the gates operating mechanism are presently in a dilapidated condition. The aging process along with inadequate/deferred maintenance has caused general deterioration of different components/structures and significant damage to the regulating gates and hoisting equipment. Any further damage to this barrage can render it non operative causing colossal losses due to non-production of agricultural crops, loss of revenue and increasing the restoration cost, adversely affecting the national economy in additional to human, social and environmental disaster.
The project envisages preparing detailed design of rehabilitation and upgradation works at Islam Barrage after review of the recommendations contained in the Feasibility Report. The envisaged project components as per the Terms of Reference for the Project include:
- Rehabilitation of Main Barrage and subsidiary weir.
- Rehabilitation and upgradation of Gates and Hoisting System.
- Raising and Strengthening of flood protection bunds, and provision of wetting channels.
- Provision of instrumentation and control system for uplift pressure monitoring.
- Design of Gate Automation arrangements for local & central control, if feasible, with suitable option of alternate power supply.
- Provision of Emergency Spillway to cater for flood flows in excess of design discharge capacity of the barrage to avoid untoward breaches.
In addition, the project also envisages carrying out Environmental and Social Impact Assessment studies, development of Environmental Management Plan including Game reserves plan of the pond area, preparing Project Cost Estimates, carrying out Economic Analysis and preparing Tender Documents etc for procuring requisite works. It may be noted that in the review of feasibility report, it was concluded that the need for emergency spillway is not warranted.