Restoration and protection of Silsako storm water channel to mitigate urban flooding in North Guwahati under SDMF for the year 2025 26 in Kamrup District of Assam

A) PROTECTION WORK Clearing and grubbing road land including uprooting wild vegetation, grass, bushes, shrubs, saplings and trees of girth upto 300 mm, removal of stumps of such trees cut earlier and disposal of unserviceable materials and stacking of serviceable material to be used or auctioned, upto a lead of 1000 m including removal and disposal of top organic soil not exceeding 150 mm in thickness as per Technical Specification Clause 201. By Manual Means In area of thorny jungle

Providing and laying one layer of Non-Woven geotextile of minimum mass per unit area of 280gms/sqm.having minimum roll width of 5.0m treated with carbon black with physical properties as given in clause no 702.2.3. over 25mm thick compacted sand layer on a prepared subgrade as a filter media with necessary overlaps as per drawing and technical specification and as directed by the Engineer in charge complete.

Providing and laying boulder apron for bed protection with stone boulders of minimum size and weight as per Table 1300.1, no fragment weighing less than 25 kg laid dry complete as per drawing and technical specifications Clause 1301

Providing and fixing of concrete lining work complete, and as per detailed technical specifications attached and as directed by Engineer-in-charge.

Supplying and installation of fabricated drain complete as per detailed technical specifications and as directed by engineer-in-charge.

Backfilling behind abutment, wing wall and return wall complete as per drawings & technical specification Clause 1204.3.8 (Sandy)

Providing & making Gabion structure with Mechanically Woven Double Twisted Hexagonal Shaped Wire mesh Gabion Boxes as per IS 16014:2018,MORTH Clause 2500, of required size, Mesh Type 10x12(D=100 mm with tolerance of ±2%), Zinc + PVC coated, Mesh wire diameter 2.7/3.7mm (ID/OD), mechanically edged/ selvedged with partitions at every 1m interval and shall have minimum 16 numbers of openings per meter of mesh perpendicular to twist, tying with lacing wire of diameter 2.2/3.2mm(ID/OD), supplied @3% by weight of Gabion boxes, as per drawing, all complete as per directions of Engineer-incharge. (Excluding boulder)

Supply and installation of Fencing made with Mechanically Woven Double Twisted Hexagonal Shaped Wire mesh Gabion Boxes as per IS 16014:2018,MORTH Clause 2500, of required size, Mesh Type 10x12(D=100 mm with tolerance of ±2%), Zinc + PVC coated, Mesh wire diameter 2.7/3.7mm (ID/OD), mechanically edged/ selvedged with partitions at every 1m interval and shall have minimum 16 numbers of openings per meter of mesh perpendicular to twist along with triangular post in every 250mm distance etc. as per detailed technical specifications and as per Engineer - In - Charge.

Excavation, loose scaling along with dismantling of existing structures by mechanical means (Hydraulic excavator)/manual means over areas (exceeding 30 cm in depth, 1.5 m in width as well as 10 sqm on plan) including getting out and disposal of excavated earth lead upto 50 m and lift upto 1.5 m, as directed by Engineer-in-Charge.

B) RCC BOX DRAIN Excavation for Structures (Earth work in excavation of foundation of structures as per drawing and technical specification, including setting out, construction of shoring and bracing, removal of stumps and other deleterious matter, dressing of sides and bottom and backfilling with approved material. I) Ordinary soil A) Manual Means (II) With dewatering ii) 3 m to 6 m depth