Publications

Regional Seminar Proceedings 1992

SESSION 2: SITE VISIT TO LABOUR-BASED ROAD PROJECTS

The site visit started with a short visit to the regional headquarters of the Labour Construction Unit (LCU) in Mohales Hoek where the project staff gave a brief introduction to the roads visited and the ongoing activities in Region South.

MAPHUTSENG - HA SELEMO - HA MONEHELA

This project consists of the upgrading of a 9.5 km motorable track and thereafter a 6.5 km trail to an all weather gravelled road with a 6 m wide roadway. The road goes through mainly rolling terrain with an average daily traffic of 30 vehicles serving a fertile area with a population of approximately 600 persons per kilometer.

Design Standards

The design complies with the Design Guidelines for Low-Volume Roads in lowland/rolling terrain. A 6 m wide camber is constructed with a crossfall of 8 % allowing for a consolidation during the construction period to 5 %.

Figure 1 shows a cross section of the standard road design in rolling terrain.

Structures

The road alignment requires two major crossings of the Maphutseng river. The first of these crossings have been completed which consists of a vented ford of 42 concrete culverts with two spillways and a continuous reinforced concrete slab (see figure 2). The total length of the crossing is 55 m. A similar crossing is planned at km 9.600.

In addition, a total number of planned structures is as follows:

• 5 vented fords
• 14 slab culverts and
• 65 drifts.

The labour-based road programme in Lesotho make use of natural stone when constructing their drainage structures. Apparently there is a good supply of skilled masons to undertake these works (see figure 3).

Work Methods

The project is executed using labour-based methods with the assistance of light equipment for compation and hauling of gravel and water.

All eartheors are carried out by manual labour. Excavation of drain, installation of culvert pipes, and mixing of cement mortar is done by hand. Gravel transported by tipper trucks but excavated loaded and spread by labour. The compaction is done with Bogmag 90S 1.25 tonne pedestrian rollers.

Gravel sources was found on the existing road alignment.

Costs

The total estimated costs of this project, including structures and administration, amount to 156 000 M/km (=54 000 US$/km). The labour input is estimated to 3600 workdays/km amounting to 27 % of the total project costs.

Compared to other labour-based projects in the region, the daily wage rate for casual labour is relatively high in Lesotho, namely 12 M/day (= 4.15 US$/day)

OLD HOEK - HA LEHLOIBI

Construction on this 6.4 km road started in February 1991 and was completed in September 1991. The road is constructed through partly mountainous terrain with a formation width of 6 m and a gravelled carriageway of 5 m. The total number of structures is 8 culverts and 14 drifts.

The average labour input was approximately 2500 workdays/km which amounted to 55.5 % of the total project costs.

The road has been put under routine maintenance by lengthmen. Apparently this was working successfully. Although the raod runs through difficult terrain with very steep sections, it was in a very good condition.