Switzerland – General construction work for pipelines – IWB, Gas & Water Pipeline Construction for Network Projects

Opportunity description

The subject of the procurement is the award of pipeline construction work on the gas and water infrastructure in the IWB supply area. Water supply pipeline construction: Temporary water supplies To ensure the drinking water supply during the construction phase, temporary water connections are installed in individual projects. The main line of the temporary supply is made of polyethylene pipes and fed from the existing water network by means of tapping saddles. As a rule, the existing connection lines on public land are connected from the main line by means of a tapping saddle and a hose. If the connection cannot be made on public land, the hose is connected directly to the water meter. The water meters must be left in the property and, where possible, not removed. Only hoses provided by IWB with valid SVGW and KTW approval may be used. The hoses are provided free of charge by IWB, must be ordered at least 24 hours before their installation, and must be installed within 48 hours in order to comply with hygiene requirements. The polyethylene pipes for the main lines may not be reused. Following coordination of the schedule or a request by IWB, the temporary supply must be dismantled promptly and the hoses returned to IWB. In addition, Annex D4 «18.1.12 Temporary Water Connections» must be observed. Water supply pipeline construction Once all temporary water connections (temporary supplies) have previously been installed for the affected properties, the supply line to be replaced can be taken out of service and disconnected from the drinking water network. After disconnection, the pipe section on the network side must be properly sealed with a cap or plug. The new supply line, including the associated fittings, is then laid. Before connecting the newly laid supply line to the existing drinking water network, a pressure test must be carried out in accordance with SVGW Guideline W4. For the microbiological water analysis, the line must first be properly flushed in accordance with the specifications in the BHB-Wasser. The flushing must be recorded and documented using a MID flow meter. The corresponding measured values must be recorded in a report and made available to IWB. A microbiological water analysis by the IWB water laboratory is mandatory. The water laboratory will be called out by IWB following coordination of the schedule. After successful microbiological water analysis and approval by the IWB installation management, the new supply line can be connected to the drinking water network. The connection lines that are not to be renovated must then be transferred from the temporary supply to the new supply line. Steel and cast-iron pipelines with dimensions of DN 200 or greater that remain in the ground will be filled by the civil engineering contractor after decommissioning. This requires connection pieces at the pipe ends, which must be installed by the successful tenderer. The components required for this purpose (see Annex C32) must be supplied and installed by the successful tenderer. Supplementary information and detailed requirements can be found in Annexes D1-D14 and form part of these specifications. Procedure: open. Review the original TED notice for the complete requirement, lots, amendments and attachments.