Pipe laying under water
Pipe laying under water requires the use of tried and tested techniques and the greatest possible care, because the difficulties involved in underwater maintenance make any servicing time-consuming, difficult and costly. Underwater laying techniques suited to the site topography and hydraulic conditions of the stream to be crossed can be used with ductile iron pipes.
A drinking water supply or irrigation project can include an underwater section:
- crossing a stream on the pipe route,
- intake in a lake or impounding reservoir in altitude,
- laying along a stream bed.
The solution chosen must comply with the following constraints:
– resistance to internal and external pressures,
– long-term guarantee of leaktightness and infiltration tightness,
– mechanical resistance of pipelines to external stresses (changes to pipeline profile, embankment erosion, floodwaters, etc.),
– ease and speed of laying given the sometimes sudden variations in water level,
– pipe, fitting and joint compatibility with the laying techniques employed.