July 2020 | FloVac

A Flovac vacuum sewerage system has been installed at the site of one of Africa’s most important infrastructure projects, funded by the African Development Fund.

Kazungula Bridge Connecting Countries

The Kazungula Bridge project which is connecting Zambia and Botswana over the Zambezi River will be a 40{1deaea03afbf3f3fb2d45caffee157f5a0ec73dd837732cad8f5061c47eb75db} boost to the GDP of the countries involved as it opens up the regions for trade all the way to the port at Durban.

The Kazungula Bridge is located at the only area in the world where 4 countries meet together. Zambia, Botswana, Namibia and Zimbabwe. One of the Seven Natural Wonders of the World, the Victoria Falls is located a short 1 hour drive from the project.

As the new Bridge opens up trade and tourism between the four countries it was necessary to set up a new border customs and immigration complex. Zhong Gan, an experienced International engineering and construction company based in Botswana, has done numerous projects for the World Bank and Botswana Government and decided to use a Flovac vacuum sewerage system on this project which services this complex.

Justin Peng the project director of Zhong Gan chose a vacuum sewer as a value engineering proposal to the client as there was a high water table which prevented deep excavations required by the original gravity system proposed. Ensuring that no sewage could overflow to the Zambezi River was also important as the area is home to elephants and others in Africas Big 5.

Installing a Flovac Collection Pit and Valve

Smart Vacuum Sewer System

The Flovac system is the first smart sewer system installed in Botswana which allows the operator to have a complete system overview. The smart system allows the operator to look at the performance of each vacuum valve in the system and independently alert operators to any potential problems.

Mr Peng chose Flovac due to the operator friendly nature of the design and equipment and the overwhelming positive feedback from prior installations that his team visited. The Water Utilities Corporation approved the system who were extremely pleased by the advancement in technology and ease of maintenance compared to other systems that had been installed in Botswana and Southern Africa.

The Flovac Team worked very closely with our local representatives Multi Waste Pty Limited headed by Andrew Davies. Multi Waste are a large domestic company , experts in water, wastewater and energy in Botswana and Southern Africa. Multi waste set up a fabrication plant for the Flovac pits and handled all assembly of the system at their head office in Gaborone prior to delivery to site.

The Multi Waste team will operate and maintain the system for the time being with support from the Flovac International Operations Group via the monitoring system.

The Flovac and Multi Waste Design and Install team

The Hilton Salwa Resort is designed to become one of the largest resorts and residential projects in Qatar. Utilizing a Flovac vacuum sewer system the resort is constructed on 257 acres of land in the Salwa area. The beach resort and villas is a massive project that includes a water park, marina, dive center, cinemas, pools, a health club, spa and a considerable retail space. In addition to the rooms and suites in the main hotel building, the resort will also include two small “villages” of family villas. (Hilton Hotels announcement)

Hilton Salwa Beach Resort and Villas

Flovac was asked to design and supply a vacuum system that would be able to handle the high flows that will ultimately be handled by the Resort. The vacuum system needed to facilitate not only the hotel but also residential areas, restaurants and the marina. The client was aware of the good work which Flovac had done at Reef Island in Bahrain (Read Here) and was particularly impressed with the monitoring system that had been installed.

The monitoring allows operators to see exactly what was happening anywhere in the network including the operation of the vacuum pump station. Mr Willem Gooren one of the founders of Flovac managed the project and was based in the Middle East for extensive periods during the projects establishment and finalization.

Smart and Safe Installation

In sandy soils, especially areas where there is a high water table vacuum systems are ideal as all of the pipework is installed at a shallow depth in the ground. A stepped profile within the pipeline design allows for some utilization of gravity while keeping the pipe shallow.

Installation of vacuum mains is a lot faster than the installation of gravity sewers as there is less requirement to de-water or pre-load the land. HDPE pipe is used often when installing in hot climates and where soil conditions are unstable.

Leak Proof

The use of a Flovac system was also important to ensure that there would be no potential leaks from the system. As all vacuum pipework is under a negative pressure sewage cannot leak from the pipe in the event of a break.

The Vacuum Pump Station is one of the largest stations in the world. Housed in a dry and air conditioned environment the two large collection tanks are connected to five large Busch Mink MM 1202 vacuum pumps. Flovac has used Mink pumps since before 2005 and so has great experience in the correct set up to maximize the ability to handle the large flows required in this project.