Water Supply and Sewerage in the 21st Century
The City of Marki in Poland, north east of Warsaw and Wodociag Marecki the Utility Company that maintains the water and sewerage systems in Marki City are quite unique.
There is a very close relationship between the utility, the City and Warsaw University of Technology. Over the last ten years they have done a number of concepts, designs and installations using a number of different technologies for specific sight conditions throughout their area. These have included vacuum sewers, gravity sewers, pressure systems and even domestic on-site treatment plants.
Prior to this initiative the City had relied on septic tanks so they wanted to ensure that they used the right technology for the right area and community. What has been tremendous about this effort is the city’s willingness to share their experiences with others around the country. Flovac applauds their efforts in this field and have been very happy to support them.
On a periodic basis seminars have been held to discuss their findings, the most recent of which was recently held in Zegrze near Warsaw. The seminar was titled (Water Supply and Sewerage in the 21st century) and included representatives from a number of local authorities and utilities from the north east of Poland. Experts were invited to talk on different subjects.
On Vacuum Sewerage Systems the speakers were:
Prof. Dr hab. inż. (prof. PhD Eng) Zbigniew Heidrich – Politechnika Warszawska (Warsaw Univerity of Technology)
Dr inż. (PhD Eng) Marek Kalenik – Szkoła Główna Gospodarstwa Wiejskiego (Warsaw University of Life Science)
Dr inż. (PhD Eng) Jacek Sobesto – Flovac Polska sp. z o.o.
Dr.inż. (PhD Eng) Grzegorz Stańko – Wodociąg Marecki sp. z o.o.
Dr Jacek Sobesto of Flovac Polska
One of the largest Flovac systems in Poland is based in the City of Marki and has over 800 Flovac valves connecting residents to the vacuum sewer. It has proved to be easy to maintain and well accepted by the community.
Vacuum Pump Station in Marki
Inside the Vacuum Pump Station in Marki
There are space for 1200 animals on Ås farm, which consists of five buildings totaling 16,400 square meters . Small sheep (sheep and goats) have been accommodated in an airy barn of 1630 sqm, while the pigs have got their own 1740 sqm building with warmth in the floor. The entire livestock unit of 7140 sqm is equipped with two fully automatic milking robots, an advanced robot that can supply feed to the cows throughout the day.
The STATSBYGG design group chose to work with Flovac after a close study of the Veterinary University of Hanover’s epidemic disease prevention unit’s use of the Flovac vacuum sewerage system installed in 2015. They cited the speed of installation, flexibility and that there had been virtually no operational issues and no contamination occurrences as the reason for choosing Flovac.
A number of tests on the vacuum system were done, including a leakage test to show that if the vacuum mains were broken in anyway there would still be no blockage. A video of that test is available here if you would like to watch it. 
To understand some of the problems you need go no further than googling “Plum Island frozen sewers”. The main problems seemed to be related to frozen vacuum valves, water frozen in the pits, gooseneck vents submerged by snow, frozen sewage in the pipework, frozen gate valves and division valves and leaks in the line.
When dealing in area’s subject to extreme cold we need to take care of how deep the vacuum mains are laid, what type of division valves are used, how the collection pit is designed, where the air intake vent should be for the operation of the valve. Many of these things can be adjusted in existing systems.
The monitoring system also makes it very easy for operators to locate the exact location of collection pits. This is also true in coastal area’s where pits can often be covered by sand during the summer months.
Merko, the leading construction company in Estonia has finished construction in Vääna-Jõesuu of Estonia’s second vacuum sewerage system – Flovac’s first system was completed last year in Leppneeme and has performed better than expectations for both the community and the operators.
“A vacuum station and waste water pumping station were built in the Puraviku tee and Nõmmerohu tee area, as well as 3.8 km of drinking water piping and 4.1 km of sewerage piping, including nearly 3.6 km of vacuum sewerage piping. The benefit of vacuum sewerage is efficiency – the sewerage pumping station does not have to pump excess water, since the watertight vacuum sewerage system takes in significantly less water from rainfall, snowmelt, leaking pipes and wells than ordinary sewerage systems. The vacuum sewerage tanks are waterproof and the tanks’ lids are 10-20 cm above the ground to prevent rainwater from leaking in from the lid,” Laidma explained.