The public sewers in the area of Tong To Village with terminal manholes at the private lot boundary shall be constructed under this Contract. The location of each terminal manhole shall be agreed with the village house owners before construction. Trench excavation shall be subsequently carried out to create underground space for the provision of terminal manhole. The village house owners require to modify the existing pipework in order to drain the sewage collected from the village house to the as-built terminal manhole. After connecting the terminal manhole with the modified pipework, the trench shall be backfilled and reinstated to the original conditions.