Engineering and environmental con-sultancy Jeffares & Green (J&G), was the lead consultants for the eThekwini municipality’s Electron Road Waste Manage-ment Facility, which won first prize for technical excellence at the South African Institution of Civil Engineering Durban Branch Awards 2014, held last month.
The facility is one of the few large-scale greenfield waste management centres in South Africa, and includes a refuse transfer station with the capacity to process 1.2-million kilograms a day. This equates to an entire soccer field covered 1 m deep in waste that needs to be handled, managed and transferred every day.
The system receives waste from local house-hold waste collection vehicles and compacts this waste into specially designed containers.
J&G tells Engineering News that each container can carry the load of at least two local waste col- lection vehicles. These containers are then transported by lower-maintenance long-haul vehicles to either a place where beneficiation from the waste material is achieved, or alter-natively to a landfill. This means that one single load by a vehicle with lower running costs replaces what would have been trips by at least four other higher-cost vehicles.
The facility, which is located north of Durban central area, nearby the Umgeni river, south of Umgeni road and east of the N2, aims to move waste management towards a more sustainable municipal service that meets new national waste regulatory requirements, reduces waste transportation costs, provide employment opportunities, enable waste to be effectively diverted from landfill where feasible, and enhance the beneficial recycling of waste, adds J&G.
Currently, much of the waste in Durban is disposed of at the Bisasar Road landfill site in Springfield Park. However, this site is rapidly approaching full capacity.
When capacity is reached, waste collection vehicles will likely need to travel to the Buffels-draai landfill site, which is about 33 km away. This is more than twice the distance that is considered economical for collection vehicles to travel.
These prohibitive transport costs have made the provision of a waste transfer system financially prudent, particularly as the Electron Road site is less than 1 km from the Bisasar Road site, says J&G.
The reduced transportation costs will also reduce fuel consumption and wear and tear on road systems, not to mention countering the major issue of congestion on the roads, thereby also providing an overall reduction in carbon emissions.
J&G says there were several challenges that it had to tackle during the construction of the project, such as adverse geotechnical subsurface conditions, which required amendments to the piling design under professional site supervision, as well as additional testing during installation.
Strict conditions and specifications needed to be adhered to and the entire design of the facility had to be aligned with the licence conditions of the facility.
J&G explains that legislation changed during the project. A specific professional team was assigned to assist the design team in obtaining the necessary approvals. The time for overall approval was lengthy, so specific approvals were obtained for stages of the work to avoid delaying the progress of construction, adds the company.
A key element was the vehicle movement modelling, which was done using selected vehicle types to assess spatial planning requirements.
Further, a specific traffic analysis had to be undertaken on the existing road network and the planned future road network.