Permanent Siphon Installation at Knipton Reservoir

Knipton Reservoir lies in the grounds of Belvoir Castle in Grantham, and was originally designed to feed the Grantham canal.

EDS were asked to install 4 siphon lines so draw down capacity could be increased at the reservoir to assure public safety in the event of a flood. Due to the differentiating levels of the reservoir bed accuracy in the installation of the lines would be paramount, therefore a range of skills and equipment were used by the EDS team.


  • The 4 siphon lines had to be connected to 66 concrete Anchor blocks all with pre-set levels.
  • The reservoir bed was made up of soft silt and had large undulations.
  • The finished levels had to be within just a 50mm tolerance.
  • The slabs and anchors needed to be positioned at the correct level.
  • 4 Duck bend Inlets were to be installed with concrete slabs at the inlet weighing up to 1.5T each.


  • GPS equipment was used to verify installation levels and location.
  • Due to poor visibility a scaffold system was used as screed rails so the dive team could level the stone fill. The team then placed each element prior to the pipe installation.
  • A Nato pontoon system was deployed with a 5T lifting gantry and dive spread, so all materials could be lifted on to the water.
  • A 6 point temporary anchor system was installed to allow precise movement of the barge to assist with placing the concrete anchor blocks.

All pipes were installed within 15mm of the design levels, another successful project completed by team EDS.