Bridgetown, Barbados – Oct. 9, 2007 -- The Barbados Association of Professional Engineers (BAPE) has already expressed concerns about the ABC Highway expansion project being undertaken by 3S Structural Solutions LLC.

These concerns include:

• the contract was agreed without a competitive tender process;

• the flyover solution was agreed before a traffic study was done; and this study was then undertaken by the same firm whose flyover proposal had already been accepted;

• the approval process for a project requiring such a large investment of public funds should have included a rigorous technical and economic feasibility study.

In addition to the company’s financial position, the qualification of a contractor to undertake this project should also have included consideration of the qualifications and experience of the key personnel, the nature of the contractor’s past experience, and a review of the firm’s litigation history.

Having observed the work in progress, BAPE questions whether full consideration has been given to the following areas which could negatively impact public safety and maintenance costs.

1. The drainage design at the superelevated sections (i.e. banked corners) of the highway between Wildey and Warrens appears to violate major road drainage engineering design principles. At superelevated sections, the entire width of the highway slopes in one direction, and rainwater would similarly drain in the same one direction. The design being built includes elongated horizontal slots near the base of the concrete medians to allow water to drain from the northbound lanes to the southbound lanes and vice versa.

During a recent period of heavy rainfall, it was observed that the volume of water flowing as a sheet across the southbound section was very significant. The danger is that this water could lead to hydroplaning, a loss of traction between vehicle tires and the road, and the loss of control of the vehicle, resulting in serious accidents. One of the worst possible locations to lose control of a vehicle is in a corner. To reduce the risk of hydroplaning, technical standards used in highway design provide recommended limits on the volume of sheet flow. Other problems associated with inadequate drainage are a potential reduction in the durability of the pavement surface and an increase in the splatter of water, which also has the potential to lead to vehicle accidents.

 
• BAPE recommends that 3S be asked to provide information on the standards used in the design of this road drainage system, and to identify where in the world they have constructed a similar road drainage design, so that the consequential effects can be examined.

2. Another safety concern is the location of the concrete islands at the Belle intersection. The islands are built along the continuation of the highway curb line, which on a highway such as this, means that they could present a collision danger to road users. It would be advisable that these be set back a minimum of 2 feet.

 • BAPE recommends that 3S be asked to provide information on the standards used in the design of this intersection, and examples of similarly constructed intersections they have designed elsewhere so that the consequential effects can be examined.

3. Based on observations of the spacing between street lighting fixtures it appears that fullcutoff fixtures rather than the previous semi-cutoff fixtures will be used. Full-cutoff fixtures put light on the ground below the fixture only, and do not emit light above 90 degrees. There is therefore less “uplight” and light pollution from the fixture.

This is desirable, however to achieve uniform lighting either more fixtures must
be used or the height must be increased – both of which have cost and energy use implications. Additionally, the lighting pole bases appear to be unusually small, raising concerns over the design wind speeds employed.