The town of Beauvais is reinforcing one of its main clear wells supplying the town centre.
Managed by the Beauvais Agency (Arras Regional Division) in collaboration with Veolia, this worksite involves the reinforcement of the connection of a well, located at the top of a slope, to the catchment wells and distribution system set up downhill.
Technically speaking, it consists of the construction on the side of a slope on 30°-gradient (i.e. 60%) terrain over a 30m stretch, of two parallel underground cast-iron ø400 pipes, the first to supply and the second to distribute.
A complex worksite
The worksite was prepared and executed methodically, including night-time operations, to guarantee the highest possible service continuity for this strategic municipal well.
The worksite was made more complex still by the presence of a concrete slab in line with the well: an obstacle partially demolished using expansive mortar with the authorisation of a civil engineering expert.
This new hydraulic structure now reinforces the single pipe, which is also a ø400 cast iron pipe and until now fulfilled a dual supply / distribution role. This secures Beauvais’s public drinking water supply.
Special machinery
The Lyon Regional Division facilitated exchanges with the Rhône-Alpes-based supplier of the walking excavator, which was transported all the way to Beauvais.
Support from SADE Ingénierie
Given the gradient of the terrain, the design and project plan by SADE Ingénierie specified a number of the structure’s technical parameters, such as abutment, locking, setup direction, height and type of backfilling. Special attention was paid to the anchor blocks at the top of the bank, which were required to retain the pipes located on the slope and prevent them from slipping.
