How to Sewer The Water Villages of Kampong Ayer
Kampong Ayer in Brunei’s capital city of Bandar Seri Begawan is a cluster of around 40 small villages connected by a 38-kilometer (23-mile) boardwalk. It dates back more than 600 years. Today, around 13,000 people live in the water village, about 3{f2ac4d1e1d40dc2e2d9280a1dfa90d854b2d8c80eba743affa37fc4ce2e16def} of the country’s population.
These Water Villages are very common throughout South East Asia down as far as PNG which has a large water village just outside of Port Moresby at Hanuabada.
Many of these villages have enormous cultural and historic value to the countries and communities that live in them. They are also major drawcards for tourists with the Kampong Ayer townships in Brunei known as the “venice of the east”
Although some of the houses are now on vacuum sewer networks, many have still not been connected. Historically having raw sewerage drop into the water below only really affected the health of the local population as many of the water people swam or fished in the same water. With the wealth of those living in the villages increasing, more problems have surfaced with detergents entering the waterways, killing off the fish and other local seafood. None of this is good for tourism, especially the odour.
The government has big plans to increase many of the houses serviced but are also finding the structural integrity of many of the houses to be a problem. Imagine laying a length of pipework between houses to pick up the sewage when the house in the middle collapses due to age.
How these houses get serviced is a very complex problem. At one of the water villages in Labuan Malaysia a gravity system was installed but proved to be a failure within a short amount of time.
The pipework sloping to a gravity main below the houses close to the surface of the water was cut many times by local residents as it was impeding the way that many residents got around the area in their boats. For hundreds of years the residents drove their small boats under their houses and around the village. All of a sudden plastic pipes were in the way. A simple solution – cut them.
In 1995 our firm was hired by the Brunei and Australian governments to design and then supply a vacuum sewerage system for two main sections of Kampong Ayer at Bolkiah A and B. The sewerage was collected into sumps pinioned below the walkways to the houses and on average 4 houses was connected to each sump. Vacuum valves were housed in small stainless steel valve boxes attached to the side of the walkways to allow for easy operator access. All of the vacuum mains were laid under the walkways back to land where the vacuum pump station and treatment plant were located.
As the pipework was laid directly under the walkways it was not visible and did not impact on the passage of the residents. The number one lesson for residents was to learn not to use their toilet as a rubbish bin. Initially blockages were common and operators grew frustrated by the number of items thrown into the system. The problem residents were easily found as with only 4 houses connected to a sump, the process of elimination was easy and the residents were educated as to proper use. Modern valve monitoring systems will make this even easier.
Our engineers received an award from the Institute of Engineers Australia for this project. Our operations group still goes to site whenever requested the the government to ensure that the system continues to work well.
The lessons which both our engineers and operators learnt from these projects has enabled us to offer clients great insights in to how best design systems for water villages, resorts and marina’s. If you would like to learn more about other Flovac projects you can read about them here. FLOVAC PROJECTS
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. 
A FLOVAC delegation was recently in Chile, in the Llay-Llay commune, where the first vacuum sewerage installation of the country is being built. As this technology is innovative for the Chilean technicians, a conference was organized for everyone interested in FLOVAC’s system, having it coincide with the formation day of the Regional Development Subsecretary (SUBDERE).
For the regional manager of Subdere Valparaíso, Eduardo Pasten, the pioneering and innovative project that is implemented in Llay Llay, can be replicated in other cities of the country. He emphasizes the importance of the presence of representatives from all over Chile, “in order to be able to disseminate, and if applicable in the regions, to implement it,” Pasten said.
Another important consideration was the low amount of power that is required for the vacuum pump station. With power required only at the vacuum pump station a back up generator can easily be supplied if there is any interruption to local power supplies.
Flovac Greece has just completed the largest vacuum sewerage system ever undertaken in Greece covering the towns of Mitrousi and Skoutari in the Serres Region of northern Greece.
The Serres region is an environmentally important area which won a European sustainable tourism award for aquatourism. A large artificial lake, Lake Kerkini was created nearby to make use of the extensive marshlands in the area. This is also behind the need for vacuum sewers in the villages as the water table is very high and actually visible on the surface in some areas.
Nearly all vacuum sewerage systems are found in coastal area’s many of which are subject to flooding from rain/storms or rising sea levels. We all understand the problems that occur if I&I is present, we all know what causes it to occur.
As technology has improved, many asset managers have embraced the ability to locate exactly where and when I&I may be occurring. A sensor on a vacuum valve giving the open/close status will also be able to tell the operator the number of activations in a day. It is very easy for the operator to set up an alert to advise if any particular valve is operating more frequently than the general average, especially during wet weather events.
When designing a gravity sewer consideration must be made for Infiltration and Inflow on the pipes, the pump stations and the treatment plant.
This historic village nestled on the banks of the Loire River near the French city of Nantes on the Atlantic coast of France is the site of the latest Flovac system in Europe.
The town is in the heart of an important agricultural area and has very flat and sandy soil, ideal for a vacuum system. It is also known as the town that first developed the beurre blanc sauce, often used in french cuisine. There are also vines on the hills around the town that grow a muscadet wine that is very popular.
The system is able to be installed with only a single vacuum pump station which is also important in an old town like Saint Julien in that space is a precious commodity. It was also important to keep energy use as low as possible, and with a single small vacuum pump station, this is possible.
Gravity sewers have been used for hundreds of years, but they come at a much higher cost than many options reports accurately record. When selecting what type of sewerage system to use, take into account the risks associated with the solution. What happens if a sewer overflows? What happens if a storm or large wet weather event occurs. What will happen if a pipe breaks. What will be the cost and what will be the risk? A vacuum sewer could be far cheaper than you realise.
Sewage leaks can occur for a number of reasons. the most common is leaking sewer pipes (this may be caused by tree roots or ground movement). A break in a gravity line can remain undetected for months or even years. In a Low Pressure Pump system a break will lead to a surcharging sewer which will be difficult to repair and costly.
In the USA the 
Owners of Marina’s know the impact of attracting houseboats and tourists if sewage is contaminating the marina area, with bad smells putting off people going to local restaurants.
Well admittedly, homeowners can still create overflows at the home and badly maintained systems will always have problems. Modern wireless and cable monitoring systems reduce this risk considerably and is a game changer.
If a blockage has occurred and sewage is backing up in the pit it cannot overflow through the manhole cover as there is a partition between the sump and cover preventing sewage from flooding at this point. If it starts to back up towards the house a high level alarm in the pit sends an urgent alarm to an operator who attends to the problem. If the problem is hard to solve or an experienced operator is not available a suction truck can be used at this point.
The municipality is located just south of the capital 
A gravity system would have required dozens of gravity pump stations due to the high water table while only 6 Vacuum Pump Stations were needed. This has reduced the energy cost of the system and also reduced the maintenance cost. As the area sometimes suffers power outages the ability to have backup generators at each station allowed for unrestricted service for homeowners. The Vacuum Pump Stations have both duty and standby pumps and are fully monitored back to base.
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.