Qualter Hasll is to start work on the Thames Barrier

The project consists of  an oil hydraulics package for a gate arm synchronisation pilot trial (GASPT) on piers Three and Four at gate Golf, as well as a drive equipment package for a shift and latch mechanism on gates Charlie and Delta on pier Seven.

The GASPT requires the introduction of new hydraulic power units and a load balancing control system which is compatible with the existing retained systems.  The performance of the new system is to be tested over the full operating range and modes of the barrier. The system will be trialed for six months under normal gate operations to prove the new hydraulics package and control system.  Operator training will take place during this period.

The current Shift and Latch (S & L) mechanisms were installed some 30 years ago and will require a full strip-down, inspection and refurbishment where required.

The Thames Barrier is one of the largest movable flood barriers in the world.  The Environment Agency runs and maintains the barrier, which spans 520 m across the River Thames near Woolwich.  It protects 125 square kilometers of central London from flooding caused by tidal surges.  It became operational in 1982 and has ten steel gates that can be raised into position across the Thames.