Underground Utilities & Trenching
NLS Contractors installs underground utilities in Riyadh, Jeddah, Dammam, Khobar and across the Kingdom: trenching, bedding, pipe laying for storm, sewer, water and fire mains, duct banks, manholes, chambers and backfill. Pipes are tested by type, and handover includes pipe test records, an invert level schedule and as-builts.
Underground work is the part of a site that gets buried, so the records matter as much as the pipe. Scope covers trench excavation and support, bedding and surround, pipe laying to line and level, jointing, manholes and chambers, duct banks for electrical and telecom cables, backfill in compacted layers and reinstatement. The networks are storm drainage, sewer, potable water and fire mains.
Pipe material follows the specification and the authority. HDPE is common for pressure mains and some drainage, GRP for larger diameters, and ductile iron where pressure, traffic load or fire mains call for it. Each material has its own jointing method and its own test, and the offer names the material it priced.
Tests follow pipe type. Pressure mains get a hydrostatic pressure test before the trench is closed. Gravity sewers and storm lines are tested for leakage and checked for line and level. Fire mains are tested to the pressure the consultant and Civil Defense specify. Each test is recorded and signed with the consultant, because a pipe cannot be inspected once it is backfilled.
Levels decide whether a gravity line works. Invert levels are set out from the drainage drawings and surveyed after laying, and the invert level schedule is part of the handover. On sabkha and high water table sites the trench needs dewatering and support while pipe is laid. In rock or basalt, trenching becomes breaking and the offer states the allowance.
Existing services are located before digging, from trial holes and the utility owner's records, and routes are adjusted at crossings. Roads, kerbs and paving cut for trenches are reinstated to the original specification, and backfill under roads is compacted in layers to the density the road specification sets.
Where the project joins a public network, the connection follows the owning authority's requirements, for example the National Water Company for water and sewer. To price the package, send the utility layout drawings, the longitudinal sections with inverts, the pipe schedule and material, the BOQ, the geotechnical report, the site city and the programme.
Specifications
- ✓Networks: storm, sewer, water and fire mains, duct banks, manholes and chambers
- ✓Pipe materials: HDPE, GRP and ductile iron, jointed by the method each material needs
- ✓Testing: pressure tests on mains and leakage tests on gravity lines, per pipe type
- ✓Levels: invert levels surveyed after laying and issued as a schedule
- ✓Authority connections follow the owning authority's requirements
- ✓Handover: pipe test records, invert level schedule, as-builts
Frequently Asked Questions
Which pipe material is used for storm and sewer lines?+
The specification decides. HDPE, GRP and ductile iron are all used, and the choice depends on diameter, pressure or traffic load, ground conditions and the authority's approved list. The offer names the material it priced.
How are buried pipes tested?+
By type. Pressure mains get a hydrostatic pressure test before the trench is closed, and gravity lines get a leakage test and a line and level check. Records are signed with the consultant.
Who approves a connection to the public network?+
The owning authority, for example the National Water Company for water and sewer. The connection follows its requirements and runs through the consultant.
What changes in trenching on a high water table site?+
Dewatering and trench support are added, so the trench stays stable while pipe is laid and bedding is placed. The offer states the method assumed and the discharge route.
Who supplies Underground Utilities & Trenching in Saudi Arabia?+
NLS Contractors (Northlane Solutions Company) supplies Underground Utilities & Trenching across Saudi Arabia, including Riyadh, Jeddah, Dammam and Jubail. Send your specification and quantities to info@nlscontractors.com or info@northlanesolution.com for a quotation.