How does kerb alignment underbidding hit Garowe roads?

A low kerb alignment bid can look complete on paper because it prices the kerb units and the laying labour and drops everything the kerb line touches. Kerb alignment underbidding risks Garowe roads through the interfaces: the kerb line is fixed by the road centreline and the drainage inlets, so any work missed at tender has to be absorbed on site or the finished levels drift.

What gets left out of a low kerb alignment bid?

The items left out are the ones that do not appear as a separate line in the bill. In general practice, kerb work needs a string line or offset pegs from the road centreline, a bedding layer, joint filler or mortar between units, and haunching behind the kerb to stop it rotating under wheel load. A bid that prices only the kerb units and the laying labour can look complete on paper.

The roadside drainage is the bigger omission. Every gully, inlet and pipe crossing interrupts the kerb run and needs a surround, a level check and a joint that will not crack when the kerb settles. If the drainage is let as a separate contract, the kerb contractor may not price the interface at all.

Ask the municipal engineer's office which road centreline and drainage records exist for the street, and read both against the bill of quantities. Walk a recently finished kerb run in the same area and look at how the contractor handled the inlets.

How does the gap show up once work starts?

It shows up as a line that wanders, a kerb that rocks, or a drainage inlet that sits above or below the kerb level. Without an agreed offset from the centreline, the gang sets the line by eye and the finished kerb can drift along the street. Bedding placed too thin or too dry lets units settle after the first rain or the first vehicle mount.

Interrupted roadside drainage is where the cost gap becomes visible. A contractor who did not price the crossings may leave the kerb running straight past a gully, or break out a section and rebuild it later at the client's cost in time and disruption. Water then ponds at the joint instead of entering the inlet.

Check the setting-out before the bedding is placed. Ask for the offset pegs, the level at each inlet, and the joint spacing the gang will use. Confirm the bedding thickness and joint detail against the project's specification or engineer's instruction, and photograph the open trench before units go down.

How do you close the gap in the tender?

Close it by making the interfaces explicit in the bill. List setting-out, bedding, jointing, haunching and every drainage crossing as separate items with their own quantities, so a bidder cannot price the kerb alone and leave the rest implied. State who supplies and places the surround concrete at each inlet.

Name a tolerance for the finished line and level, and say how it will be measured, then confirm that figure against the project's specification or engineer before the tender goes out. Ask bidders to submit their setting-out method with the price, not after award.

Before comparing bids, ask two suppliers for written quotes on kerb units and bedding material so the client knows the material floor of the price. Request the contractor's record from a similar kerb job and check the inlet details on that job. A bid that sits below the material floor plus a realistic labour allowance is a question to put in writing.

What to do next

Pick one street where kerbs were recently laid and walk it from end to end, noting the level of every inlet against the kerb and any joint that has cracked. Photograph what you find, then submit the drawings and the bill of quantities to the responsible engineer and ask for written confirmation of the crossings in scope.