• Load-bearing bottom with a waterp

• Load-bearing bottom with a waterproof course, canal walls of reinforced concrete grade 200 with 1x2 cm aggregate,
• An asphalt concrete joint with three waterproofing courses for every 5 m length of canal,
• A cross beam made of reinforced concrete grade 200, size 15x15 cm every 10 m along the length of the canal, to resist the static water pressure from inside the canal.

83. The above structure is able to reduce water loss to approximately zero and will result in an anticipated life of up to 25 years.

b. Technical Option No.II
84. This option involved the concrete lining of main canal, primary canals, secondary canals, and facilities along canals as follows:

• Canal bottom with bedding concrete grade 100 of 5-10 cm thick,
• Load-bearing bottom with a waterproof course, canal walls of reinforced concrete grade 200 with 1x2 cm aggregate,
• An asphalt concrete joint with three waterproofing courses for every 5 m length of canal,
• A cross beam made of reinforced concrete grade 200, size 15x15 cm every 10 m along the length of the canal, to resist the static water pressure from inside the canal.

The above structure is able to reduce water loss to approximately zero and will result in an anticipated life of up to 25 years.

c. Technical Option No.III
85. This option involved the concrete lining of main canal, primary canals, and facilities along canals as follows:

• Canal bottom with bedding concrete grade 100 of 5-10 cm thick,
• Load-bearing bottom with a waterproof course, canal walls of reinforced concrete grade 200 with 1x2 cm aggregate,
• An asphalt concrete joint with three waterproofing courses for every 5 m length of canal,
• A cross beam made of reinforced concrete grade 200, size 15x15 cm every 10 m along the length of the canal, to resist the static water pressure from inside the canal.

The above structure is able to reduce water loss to approximately zero and will result in an anticipated life of up to 25 years.

D. Construction and Site
1. Site Compatibility with Construction Plans
86. During selection and screening of subprojects, the consultants received unanimous agreement from Lang Son PPC, its DARD and Loc Binh District People’s Committee for the proposed design and scope of the rehabilitation. While additional investments were requested, the higher unit cost would have rendered the investment un-economic. For this reason, the consultants have recommended the reduction of the lining activities to cover only the main and primary canals and to omit the 4 km of road rehabilitation requested in their proposal. The compatibility of the site to carry out the proposed rehabilitation is appropriate given its previous use was for the same functional purpose - irrigated cropping activities by resident farmers. Whilst there may well be some realignment of secondary and tertiary canals during the detailed design phase, such adjustments are to be made within the context and agreement with local beneficiaries and will involve no major change to the land use purposes of the existing site.

87. No changes are contemplated to the reservoir structure other than the installation of three phase power to the water release gates in the weir wall to automate water management in the system. This can be easily accommodated within the existing structures already established on the reservoir. The rehabilitation process will involve small machinery and vehicular access to the irrigation command area that will be needed in the construction process. The works contract shall specify that the irrigation command area must be returned to its original condition prior to rehabilitation after completion of works.

E. Land Acquisition and Resettlement Plans
88. The main impact from the Lang Son Irrigation Rehabilitation will be permanent loss of small areas of land adjacent to the works and minor damage to structures, crops and trees, and temporary loss or disruption of the use of land or other assets caused by construction works and the movement of construction plant and materials to and from work sites. Few if any people will be severely affected by land acquisition. In accordance with ADB’s resettlement procedures, the subproject is classified Category B. Full resettlement plans (RPs) (as required for Category A projects) will not be required because any potential subproject with significant resettlement impacts will not be eligible for funding under the overall Project. A short RPs has been prepared for this subproject as land acquisition and resettlement impacts are confined to within the limits of Category B.

89. A field survey of the area to be rehabilitated showed that, as a direct consequence of subproject implementation, up to 16 households could suffer loss of assets apart from land. These assets include a number of toilets and kitchens. Exact numbers will not be known until detailed designs are prepared. It is highly likely that the engineering works can be completed without