Projects associated with new developments are generally a lot easier to design as if there is no drainage currently in situ then a new and compliant design are a lot easier to coordinate. A complete blank canvas means all new drainage can be installed without a need for old, potentially damaged pipework needing to be considered.

The scope of work can easily be based off the site requirements, topography of the land and space available. Details need to be compiled of the population needed to cover, proposed discharge point, location of services within the area.

However, some jobs require an element of both consolidation of old and installation of new. This was certainly the case for one project we recently undertook in North Yorkshire where the new and the old were part of the same scope.

When the initial enquiry came through, we were asked to compile a proposal for a new package sewage treatment plant to cover an existing property and a proposed new building, the design was to cover 12 bedrooms over the 2 properties on primarily a Bed and Breakfast basis along with a small catering facility.

We therefore proposed to install a new Klargester BioAir 7 premium package sewage treatment plant to replace the archaic septic tank and incorporate the new system. All groundworks for the drainage were to be included for within the scope of work.

A few elements of the installation needed to be taken into consideration, the outfall was to the nearby watercourse which required some elements of the drainage to be installed down a bankside, this required some temporary landscaping works to be undertaken along with a skilled machine operator to carry out the trenching.

Overall, in excess of 100 metres of new gravity drainage was installed on this project, including works through the yard area and also down to the watercourse. This included a range of new manholes as required by Building regulations, these were located at any change in direction, an inlet inspection chamber prior to the new BioAir 7 and an outfall sample point.

The new system was installed in line with the manufacturer’s guidelines in a full concrete surround, the material used as a backfill on these systems is vital to ensure that the system remains correctly sited, and the structural integrity of the unit is not compromised.

Typical wintery weather conditions gave our team some minor challenges where water levels in the watercourse were raised for a period and the ground conditions were sodden at best making the reinstatement to a machine finish more complicated.