In 2014 Interpolis company won the tender for implementation of design and overhaul of water supply in Chelyabinsk.
Tender includes 16 facilities located in almost all areas of the city. Over 10 km pipes of water supply network shall be laid. A full range of works for includes design, procurement, installation and putting renewed pipeline into operation. All works must be done in a tight schedule - only for 4 months.
The conditions of works are rather challenging: all repair works should be done without shutting down the operating network, in order to don't shut off or restrict water supply for the residents of Chelyabinsk. Installation of new pipelines run parallel to the existing pipes, close to them, in conditions of constant accidents of old network, often almost "waist-deep" in water and mud.
Interpolis uses innovation techniques of pipe-laying such as trenchless technology. Most of repair work is carried out by the method of horizontal directional drilling. The advantages of this method of pipe laying are obvious. It is executed without breaking the roadway and violations of the existing landscaping, and therefore there is no need to block roads and create additional inconvenience for the residents of the city. It also significantly reduces total cost of the work. Of course, company must have the appropriate equipment and professional workforce for such work.
Some part of the repair work is carried out with the traditional cut-and-cover method which includes such stages as excavation of trenches, laying welded pipe sections, backfill and restoration of the roadway and landscape. Performing all of these stages requires a lot of time and labour costs as well as well-managed work organisation.
Some of completed projects of 2014 can be noted as technically interesting.
One of them was overhaul of water main in Kalininsky district in Chelyabinsk where about 100 meters of pipeline were laid on the bottom of the Miass River. It is rather rare in urban areas as well as technologically and organizationally unique, and its successful implementation requires an appropriate experience and a high level of engineering and technical training.
The second one was water main under Vasilevskogo Street in Leninsky district in Chelyabinsk. More than 200 meters of pipe 500 mm in diameter were laid trenchless without roadway breaking.