In a step towards greater uniformity and quality, the Ministry of Public Works and Communications has prepared and released its own set of engineering standards.The standards were first discussed at the Ministry of Public Works and Communications Engineering Conference held in May. They were drafted by the Agency’s Works Services Group who compiled them with the assistance of an international consultant.The standards are based on a combination of those used by the American Association of State Highway and Transportation Officials (AASHTO), the Transportation Association of Canada (TAC) and the Department of Transportation (DOT) among other regulatory bodies.Despite the fact that the Ministry of Public Works generally has oversight for the construction of major public roads, an engineer within the Works Department told this newspaper that there are other agencies involved in the construction of roads across the country that serve a number of different purposes.For instance, the Ministry of Housing, and the Ministry of Agriculture; the roads constructed by these two agencies do not meet the requirements for roadway construction as issued by the Ministry of Public Works. In the case of the Ministry of Housing, the monies allocated for newly developed housing schemes do not grant leeway for the construction of an extensive network of paved roads running throughout a scheme, instead the main roads are paved and the smaller streets are not. Meanwhile the Ministry of Agriculture may require access roads of only a certain width into certain ‘backdam’ areas, forming yet another category of roadway. A similar case is found with the roads developed by the Guyana Geology and Mines Commission for access to mining areas.The trend continues with the other agencies that have some part in the construction of roads in the country – the Ministry of Finance (especially through SIMAP) Programmes,Soccer Jerseys China, Regional and Neighbourhood Democratic Councils as well as private developers.The Engineer noted that although the standards have been drafted and sent out to a number of the agencies, none of the agencies are obligated to adhere to them with the exception of the Ministry of Public Works. He said that most of the other agencies make compromises on the standards because of cost related issues.The matter of making the standards a de facto part of road building anywhere in the country is one that has to come from the Cabinet level or perhaps at a Parliamentary level. If the standards were adopted across the board they would however need to be revised to incorporate the different road building needs, styles and construction methods of each agency that has some oversight for the building of roads. In other words, the standards would have to become a comprehensive road building guide with multi-agency input.Presently, the standards classify roads as arterial, collector and local roadways. Arterial roads are highways that provide direct service links to major population centers. Collector roadways are those which provide direct service to towns and link up with arterial roads. And local roadways are those which connect various regions of a Municipality and tie into the system of collectors. As it stands, the only agency that designs and builds arterial roadways is the Ministry of Public Works.Using the traffic flows and the type of roadway as a guide, the need for paving is determined. The standards designed by the Ministry of Public Works also take into consideration the geometrics of that road. Geometrics in this case meaning the dimensions of the carriageway (where the traffic moves) and the shoulders of the roadway.According to the engineer, there are a number of factors that are to be considered when designing pavement. It should be strong, meaning that there will be no surface cracks when subjected to the weight of vehicular traffic, and water should not undermine the road.It should be smooth enough for travel but provide enough traction for safe driving. And most importantly in a country like Guyana a road design should be economical both in terms of its initial construction and its recurring maintenance cost. The type, numbers and the frequency with which vehicles traverse the roadway are all used to determine the loading for that particular road.As the Engineer explained it, because the conditions vary at every construction site for every roadway defined under the standard, there is one minimum requirement that must be adhered to – the minimum structural number. The minimum structural number is an index that tells an engineer the total pavement thickness required and the materials used for building roads – asphaltic concrete, aggregate in the form of crushed stone and sand as well as clay as a base material. Each of these materials has its own structural number and they can be combined in varying proportions that add up to the required structural number of the road.Although the standards have been shared with other executing agencies for roads, the Ministry of Public Works will not be policing the standards and they have yet to make them public or accessible to the media, however, interested institutions such as the University of Guyana or private consultants have requested and received copies of the standards.
