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EPA demands that vacuum technology to be used at Eco Resort

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The Couran Cove Eco Resort in Queensland Australia is an award winning environmental success story for Flovac and for our client.

Designing to best environmental practices which included refunds to staying guests if they used less than average electricity and water during their stay.  A vacuum collection system was a natural choice, chosen for its ease of installation and environmental credentials.

2,000 visitors plus staff with a swimming pool, function center, laundry facility, restaurant and marina.

The system at a glance

  • 1 Vacuum Pump Station
  • 2,000 Guests plus Staff
  • Villa’s, apartments and cabins along with a conference facility, restaurants, sporting areas, offices and marina pump out facility
  • 215 Collection Pits
  • Fibre Optic Monitoring System

System Benefits

The developer showed a strong preference for a vacuum sewerage system as he saw it offering significant benefits in this development over each of the alternatives. These benefits were identified as:-

  • Ability to handle low flush toilets thus reducing the ultimate treated water disposal problem
  • Minimal impact on the landscape during construction with shallow trenches
  • Maximum water recovery for reuse in the re-vegetation irrigation system
  • Construction route flexibility thus minimizing the damage to vegetation
  • Ability to transport grey and black water in the one small bore pipe
  • Ability to safely lay all services in the one trench with minimal spacing
  • Zero infiltration and exfiltration
  • Ability of the system to service the entire site with one centralized pump station
  • Ability of the scheme to service the Boardwalk accommodation and even the boat sullage

Couran Cove Web Page

If you would like more information about this project or would like a free concept and budget for your next project please contact Flovac Engineering by clicking here

Vacuum Valve and Collection Sumps were located under the walkways in stainless steel vessels.

 

 

Award winning project for Flovac as a Commerce by Design award in the annual Gold Coast Urban Design Awards

 

Able to handle seasonal flows from different areas within the resort. The remote beach restaurant is 3 km from the main resort

 

Growing Pains or Growing Old Pains – What best describes your old gravity sewer?

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What happens when your sewerage network gets too old? Your old clay pipes have cracked or are filled with roots, every time it rains it seems like its a direct line from the clouds to the Treatment Plant. People in the community start asking why you are spending a load of money on treating rainwater instead of just sewerage.

If you are part of a coastal community it could be worse, your old broken  pipes could be letting seawater into the system every time there is a high tide or major storm. Salt water can cause major problems at the Treatment Plant. For communities like Miami Beach who get storm surges flooding their sewers and closing their beach on an increasingly regular basis it can cause major economic and health risks. Santa Pola in the Alicante area of Spain found that the impact of global warming and rising sea levels caused a complete failure of their old sewer system.

The town of Santa Pola with over 10,000 homes replaced their whole gravity sewer system with a Flovac vacuum sewerage system. As vacuum mains are laid in shallow trenches it was possible to skirt around, above and below exiting infrastructure and eventually replace the network. You can read more about that project here.

It could be that the old gravity sewer system with large heavy pipes just wasn’t suited to the ground conditions that are often found near the coast or in swampy area’s and that over time they no longer have the correct grade to remove the sewage or have pipes that continually break allowing ground water into the system as well as blockages. This occurred at Hope Island on Queensland’s famous Gold Coast.  Gold Coast Council have developed a Master Plan and slowly replaced a number of area’s with vacuum sewers. When the original gravity sewer was laid, there was no choice, developers were racing to put up houses and council at that stage had no experience with vacuum sewers and so deep gravity mains were installed. Almost immediately problems were noticed as the ground subsided in different area’s. Sewage backed up in pipes and was unable to flow as the grades first allowed for in the networks were no longer the same.

When looking at upgrading a gravity sewer, pipe relining can be an option, but in many cases this becomes an ongoing expensive option and be too difficult in a large network. Some utilities just look to replace the old pipework, but in most communities this is just not practical. This could mean uprooted gardens, roads out of use for a number of months, noise, dust and a huge cost.

For many communities it is the size of the town that has changed dramatically over the years. In most cases this has meant an increase in the population as people move from the city to the coast. Developers move into the fringes of the town. Planning regulations change allowing for sub dividing of the old large land blocks or height and density changes. This puts pressure on existing sewers that are already not coping due to age and lack of maintenance. This has happened, not only in small coastal towns but in larger developed cities like Abu Dhabi and New Delhi. Vacuum sewers can be used to supplement the towns aging sewer system, loads can be taken off the main system by a series of collection pits and shallow pipework.

Flovac vacuum sewers have shown time and again, their versatility. This means either their ability to handle density changes or climate changes. It might even mean changes in ground conditions as happened in Christchurch New Zealand when they suffered from a terrible earthquake. The old gravity sewers in the city and surrounding suburbs broke and left residents with no service for months. Vacuum sewers have now replaced a large portion of the gravity sewers in Christchurch and although difficult has proved to be a better long term  solution for the residents and operators. Christchurch systems

Vacuum sewers should not be looked at as the only solution in many of these towns. In some cases a combination of grinder pumps, gravity and vacuum is going to be the better result for the community. Whether the problem is growing pains, or growing old pains a vacuum solution might offer the versatility that you need.

Marina Vela Vacuum Sewer System, Barcelona.

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Marina Vela, the newest upscale Marina in the heart of Barcelona has opened for business. The new Marina which utilizes the latest in Flovac vacuum sewer technology has 136 marina berths which can cater for boats up to 50 meters in length.

Barcelona’s new Hotel W will be attached to the marina along with a number of restaurants, bars and shops. The marina is very central to city centre and the beach.

Flovac has installed a number of systems in marina’s In Barcelona including Port Vela, as well as in a number of other countries worldwide include Flisvos Marina in Greece, Marina di Pisa in Italy  and Marina Hindmarsh in Australia. The latest marina project outside Barcelona will be in Canouan in the Caribbean and will be profiled in an upcoming newsletter.

Marina Vela  has the latest in monitoring systems which allows the operator to be aware of any potential overflows, breakdowns or misuse by the boats crew. Not only is sewage taken care of but also any bilge water is taken off the boat and can be separated and reused. Details in Spanish can be found on our Flovac Spain website 

Largest Vacuum Sewer System in Greece is Completed

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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 system which has two large vacuum pump stations, 800 collection pits and 45km of vacuum pipework. The system takes away the sewage of 3,600 residents in Mitrousi and over 4,100 residents in Skoutari. This makes it one of the largest systems ever installed in Europe.

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.

As the vacuum sewer pipework can be laid at minimum depth and avoid de-watering is was seen as the only way in which a proper sewer system could be installed.

Vacuum sewer system are also popular in Greece because of the flexibility in the laying of the pipe. On many occasions archaeological artifacts are found during the construction of a system and rather than hold up construction for weeks or months while a site is investigated, the vacuum pipework can be diverted around a sensitive area, thus saving time and money. The Serres region is known for a number of antiquities including important sites from the time of Alexander the Great in 300 BC.

Flovac’s partners in Northern Greece, Environmental Engineering S.A., based in Thessaloniki, are the largest installers and operators of vacuum sewers in Greece and have been involved in a number of important projects since it was founded in 1993. The company principals Miltos Chatziiliou and Spiros Kolovoi have been very involved in engineering design, product development,

construction works, treatment as well as the operations and maintenance of a number of systems. Miltos works very closely With Harry Gerpinis who looks after Flovac’s interests in Southern Greece and has been instrumental in a number of significant projects including many large marina’s.

Flood Affected Sewer Systems

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Vacuum sewerage systems are ideal in areas that are subject to flooding

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.

We have operated a number of systems during major floods without the system going down. In one Sydney system major floods occurred every two years (see photo above), our operations contract stated that if any homeowner could not continue to use their plumbing they would be put up at a hotel at our cost. Happily we did not spend a cent on hotel costs.

For the vacuum valve to meet the European standard it must be able to operate under a full 10 inches of water. To meet the Australian standard it must operate without problem under 18 inches of water. By ensuring all hose clips are properly in place and the controller breather is clear of any water , the system will continue to operate.

In area’s where flooding is common we tend to put the controller and controller breather in a pillar besides the pit to ensure that the operator can still fire the valve without trying to access the pit through the flood water which might not always be possible.

Water infiltration from the homeowners property.

We have found that the main source of stormwater entering a system comes from the homeowners property. In some flood areas we have seen that certain sections of the town will regularly go under water. This usually means that residents have to be evacuated and in the past the water inundation from that area could risk the whole system. In this case we would install a remotely controlled division valve that would cut off that section of the town from the vacuum system. It is controlled from the operations base so that operators are not put at risk trying to isolate the area.

In some older towns we find that some houses, or more often camping grounds or caravan parks are set at ground levels

that are blow the legislated 100 year old flood levels that people can build at. If we find houses affected in this way, they must pump into the vacuum system rather than drain into it so that the system is not put at risk.

Candycanes/Gooseneck house breather vents when placed on properties will often be a source of infiltration, usually due them either being cut down by homeowners who object to them being in the middle of their yard or by gardeners knocking them over with their lawn mowers. At times they are placed too low to the ground, under the flood level. In these cases we would install a  Dedicated Pillar or think carefully about where the gooseneck vent is placed. Putting it in the middle of the yard risks it being cut down allowing water to enter the system. Putting it at the roof or garage top or against the house wall will limit water entering the system.

Smart Monitoring

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.

Once the operator has established which collection pit is activating more frequently than the other valves in the area, they can then troubleshoot the problem. The likely problems are that the homeowner has cut their house vent or inspection point to allow rainwater to enter the system or may have connected up their stormwater system to the sewer system or have a cracked gravity line feeding from the house to the pit. A letter to the homeowner to make the necessary rectifications is required.

There may also be groundwater or stormwater entering the collection pit due to incorrect pipework entering the pit allowing for water to enter. This is usually picked up at commissioning, if not should now be rectified.

You should also make sure that the pit lid is made for area’s that have flooding and has a seal and no holes to allow water to enter. the pit should not be located at a low point in the street.

The monitoring system makes it possible to identify these problems and fix them. this is not possible in a gravity system.

System Design

When designing a gravity sewer consideration must be made for Infiltration and Inflow on the pipes, the pump stations and the treatment plant.

Stormwater cannot enter the vacuum system via the vacuum pipework as it must remain tight for the vacuum pressure to hold tight. If a break occurs in a main it is immediately noticed and repaired.

An allowance is made for I&I but only for a small amount of the network, that being the homeowner gravity lines. So the system is not designed for infiltration and all steps must be taken to ensure that it does not occur. Luckily in a vacuum system the source of any I&I can be located.

If you have any leaks into your system, contact an expert for advice.

Exfiltration – Why Can’t Vacuum Sewers Leak?

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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.

When you reflect on the damage and the cost of exfiltration from sewer networks the statement that we often hear ‘gravity sewers require no maintenance – we just put them in and leave them be” is wrong and does not reflect the true risks of not only gravity systems, but also low pressure systems as well as old septic tanks and combined sewers.

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.

With Low pressure systems a pipe break is easier to detect as some local TV news anchor is excitedly showing the 50 foot geyser in the middle of main street.

Overflows can also be caused by the system being inundated with stormwater which overwhelms the entire system allowing polluted stormwater to enter waterways.

A vacuum sewer piping network is leak tight, as it operates under a negative pressure any break cannot allow exfiltration to occur and as the pipe is less than 1/3 full at any time there is no surcharge.

What are the main problems if exfiltration occurs?

Health Issue’s

In the USA the Centres for Disease Control and Prevention (CDC) and the US EPA regularly report on annual deaths due to sanitary sewer overflows.  Sickness is widespread with the most common symptoms being diarrhea and nausea. This can be caused not only by drinking the water but also by swimming and eating shellfish and fish.

Of greatest concern is infectious disease, such as the contamination of Wallis Lake oysters in Australia with the sewage-derived virus hepatitis.

In Baradine a small town in Australia The Department of Health reported a 30{f2ac4d1e1d40dc2e2d9280a1dfa90d854b2d8c80eba743affa37fc4ce2e16def} reduction in student sick days at the local school once a new vacuum system was installed. In far north tropical Queensland the introduction of a vacuum system led to a reduction is diseases caused  by mosquitoes.

Not only is the health of the broader community at risk, there is also a risk for sewer operators needing to deal with overflows and backed up sewers.

Environmental Issue’s

In the nineties nearly 20{f2ac4d1e1d40dc2e2d9280a1dfa90d854b2d8c80eba743affa37fc4ce2e16def} of Florida’s manatee population died due to an algae bloom which had intensified due to sewer overflows.

On average 140 beaches in the US are closed or have warnings due to sewage contamination. KawaKawa Bay in New Zealand which had been a source of shellfish and a place to swim for the indigenous Maori population for hundreds of years was completely closed for ten years due to sewer overflows from a growing seaside community. It was only after a vacuum system was installed that the bay was reopened.

Sewage contamination readily degrades in the environment, but in water it can soak up oxygen from the waterway. Low oxygen levels can kill large numbers of fish and other aquatic life. Sewage also has toxic levels of ammonia that can poison aquatic life, along with many other contaminants.

Overflows contribute nutrients and sediment that encourage the vigorous growth of invasive weeds, such as willows, blackberries and privet, which often choke native species along stream channels and banks.

Aquaculture and Tourism Impact

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.

Dal Lake, one of the most scenic tourist spots in Kashmir has suffered terribly from sewage overflows from nearby towns but even worse from raw sewage entering the lake from houseboats on the lake.

Tourists going to Brazil for the Olympics and the World Cup were told not to go near the beaches. Dr Daniel Becker, founder of the nonprofit Center for Health Promotion in Rio, said: ‘In Rio, if you’re going to the beach, you’re going to sewage.’

“A sewer line clogged with grease caused raw sewage to spill into the Five Mile River , forcing the closure of shellfish beds from Darien’s Long Neck Point to Wilson Point in Norwalk.”  This is a common story, found around the world where sewage overflows can affect not only health but the livelihood of businesses.

Financial and Reputational

In many countries fines are being issued to water authorities if sewage overflows occur. The Environmental Protection Agencies must report any overflows and state and federal reporting is mandatory. If there is a death related to a sewage overflow that could of been prevented then lawsuits and possibly prison could affect senior people within the wastewater industry.

Newport Bay in California had to close its beach to swimmers and divers on one of its busiest weekends due to a large sewage spill that was caused by a sewage pump stopping, flooding the streets and beach. Not only was the beach closed for 4 days, ruining many tourists holidays, it also financially hurt local small businesses including restaurants who are talking about legal action against the Costa Mesa Sanitary District. The District has now been fined $503,000 by the regulators of  The Santa Ana Regional Water Quality Control Board. Sadly it didn’t end there with a smaller spill caused by tree roots blocking a sewer main causing beaches to close for three days the following year.

There are always lots of big fish down at the lake because.

The first problem, is how do you know that you have a leak or overflow.Usually it is because sewage has been spotted at the local playground/beach/street. Or because you know from flow meters at the Treatment Plant that not all the flow is reaching it. In New Delhi it is estimated that only 60{f2ac4d1e1d40dc2e2d9280a1dfa90d854b2d8c80eba743affa37fc4ce2e16def} of all sewage collected is actually reaching the treatment plant.

Even with new technologies it is difficult to find leaks when the pipes are buried 10 metres (40 feet) underground. It is also very expensive to fix that leak. Not only is there potentially a disruption to service, a closing of roads the restoration of the surface, you need to find an allocation in the budget to make those repairs.

Why doesn’t all this happen with a vacuum sewer?

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.

Firstly though, all vacuum mains are fairly small diameter, 125, 160, 200 dia (6,8,10 inches) and laid at a very shallow depth (Under 1.5m or 6 feet) So if there is ever a break it can be reached quickly and repaired without loss of service or expensive restoration. All pipework has to be pressure rated so it is a lot thicker than traditional sewer pipe.

Sewage is transported quickly in the pipe by air. The pipe is full mainly of air and not sewage. Large sections of the pipe are empty with sewage only collecting at lifts in the system. All pipework is under a negative pressure created at the pump station. If a pipe breaks, it sucks in and does not let any water leak out.

Once there is a leak or break in a pipe, the vacuum pump at the vacuum pump station must run longer. This creates an alarm which is transmitted to the operator. He is made aware that a leak is occurring in the system, this may be at the vacuum pump station, at a valve pit or in the pipework. A reticulation monitoring system will automatically notify the operator if there is something blocked in a valve or there is a break in the line. When pressure is monitored at each pit it is easy to detect in which section between two pits a break has occurred.

If a break has occurred, it would usually be due to an outside contractor breaking the pipe, tree roots rarely get into vacuum mains as they are pressure pipes. As a break is at minimum depth it is easy to locate and repair and no sewage would have leaked out.

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.

At the Eco Resort near the Barrier Reef in Australia a vacuum system was chosen to ensure that no sewage could affect the local ecology nor leak into the swimming lagoons which would have closed the resort.

As any leak in the pipework, must be repaired immediately, no stormwater can enter the system during wet weather events. This is common in gravity systems where breaks may go unnoticed. This means that the vacuum system can never be inundated with stormwater and wet weather infiltration is not included in design parameters.

Due to the velocity of water in the pipes there is not build up of fats or grease and wet wipes or other objects do not cause blockages at the vacuum valve nor in the pit. See Video for information.

Vacuum Sewers are considered to be the Low Cost of Sewage collection, both in capital costs and also in maintenance costs. Risk is a very important consideration.

Marina Port Vell Barcelona installs Flovac System

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On April 27 2015, Flovac commissioned the vacuum system at the Marina Port Vell in Barcelona. Known as one of the finest new marinas for Super yachts in Europe, the owners saw the use of the Flovac system as essential.

The system designed and installed by FLOVAC includes the discharges from buildings in the Marina such as the restaurants, offices, locker rooms, gym, etc … and residences on the boats moored in the Marina.

Wastewater and Bilge Water

The vacuum system has two vacuum networks, one for wastewater generated in the Marina (waste water) and a parallel network where bilge water, which requires pre-treatment to collect the sewage discharged in port .The network of pipes, placed around

the perimeter of the marina, carrying the waste water has vacuum generated by a single vacuum station located in the Marina. It is the single point of electricity needed for the whole system. FLOVAC vacuum valves, which are located in different collection pits are pneumatically operated with this setup, FLOVAC has already installed four vacuum sewerage works in the area of the Port of Barcelona.

No Leaks from the Sewer System can occur

The vacuum system ensures the impossibility of discharges into the sea , is the most economical solution in terms of execution of work, since by its very nature design , the network of pipes need not be buried deep underground and no intermediate pumping.

Moreover, in this case, the system is equipped with a remote control system that allows the owner to know exactly everything that happens anywhere in the sewer.

User Pay for Sewage Discharge

Flovac also designed software to control the discharge of sewage from yachts to the Marina and can accurately invoice by litres of discharge to the sewer. As a result, Marina Port Vell prevents sewage dumped at sea and in return gives them a MARPOL certificate.

MARPOL 73/78 is an international convention for the prevention of pollution at sea. The convention includes regulations aimed at preventing and minimising pollution at sea from ships, and this includes both, accidental pollution and pollution from routine operations.

Center for Preventing Disease Epidemics in Animals using a Flovac System

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The highly reputed Veterinary University of Hanover is, among others, engaged in the Pathology and Epidemiology of livestock, especially domestic cattle and pigs. After 2.5 years of construction time, the first part of the new research Center for Emerging Infections and Zoonoses (RIZ), with a total investment of 37 mill. Euro was opened in the end of 2014. The second part of the complex, with total 2000 sqm and 40 laboratories will open beginning of 2015.

UntitledFor the need of a safe dewatering of the potential contaminated wastewater from the test fields and laboratories, a vacuum sewer system was chosen. A vacuum system is the first choice for such a demand, due to the fact that in any case of leakage no liquids can emerge.

Totally 19 collection units, with FLOVAC  3” vacuum valves, are installed in the different stables and 85 wash bowls are dewatered with FLOVAC vacuum dewatering boxes. Also special designed vacuum floor drains are built in.  In addition FLOVAC stainless steel vacuum toilets are used. The vacuum piping, with a total lengths of 800 m is installed in the cellar of the building.

A small vacuum station, for generating the needed vacuum, completes the system. Only this component of the system needs power supply, all other components are operated pneumatically by vacuum.

Under the aspect of epidemics protection, a vacuum sewer system is the best opportunity for transporting waste water in the research center.