Camden Sewer Connection – Thames Water London

Client: Hutton Construction Duration: 2 Weeks Value: £15K - £20K

The aim of this Thames Water new sewer connection project was to connect a new block of flats onto the main Thames Water sewer via a new manhole construction in the highway.

The required shaft location in the public highway for the new Thames Water manhole will be marked located using Thames water asset drawings. Before any operative enters the shaft the gas monitor must be lowered into the shaft and left for five minutes to allow for the detection of any toxic gasses.

The top frame and corner sheets will be installed and secured to a guide frame at ground level. Hanging chains will be used to secure the frame to the corner sheets. The remaining open faces will then have trench sheets placed interlocking around the perimeter of the shaft. Excavation will then proceed to the required depth (existing sewer depth) using the dig and push method. A second frame will be installed at 2.5m from ground level and all sheets are to be firmly pushed/toed in. A hand rail system fixed to the trench sheets (as below) will be securely placed around any open excavation at all times.

Upon reaching the required depth and locating the TW sewer the crown of the existing sewer pipe will be cut of and removed creating a channel. Concrete will be placed around the channel and new sewer pipe ready to receive the new manhole rings.

All operatives working within the trench and on the live Thames Water sewer are to have been trained to city guild medium risk level in confirmed spaces and adhere to the procedures at all times. Operatives on site will be experienced in trench and shaft work & Public Sewer Connections.

When the trench is open back to the site the 150mm diameter lateral pipe will be laid to line and level on a shingle bed and surround and terminated at the property boundary. The type 1 will be spread and compact in 150mm layers until the desired level is achieved.

On completion of connection to the foul water sewer and of the back fill procedure of the trench the specified asphalt will be laid by hand to complete the works. This will complete the new foul water sewerage connection.