Here are some examples of how WaStop® can prevent high water levels forcing water back up into the pipeline.
WaStop chosen to protect Forest View from flooding
|Location: Forest View
Customer: The Village of Forest View
Originally Forest View had a combined sewer and stormwater system. As the area became popular development occurred which lead to more hard surface areas, which lead to higher runoff during rainy periods. This became such a problem that, in the 1960’s the sewer and stormwater system was split to ensure that high rainfall events didn’t overload the sewer system causing backflow into residential properties. The two split systems joined again just before the treatment plant. The construction of a dedicated stormwater outfall allowed a complete split of the two systems with separate storm and sanitary sewers.
Despite the split systems the area of Wenonah Avenue still suffered from flooding in the lower areas during high rainfall events. This was caused by under dimensioned storm sewers. Several options were available for solving the issue. Two solutions were seen as being effective in stopping the flooding, without causing issues to other nearby areas. One of these solutions would be to lay large pipes in order to store the water until the rainfall subsided and the system could drain. The negative side of this solution was the cost and the intrusive nature of the work. To thoroughly assess this potential solution a study was made of the soil in the designated area however it was deemed that the soil was not appropriate for this type of work so another solution was investigated.
Brad Clark, a Principal at Hancock Engineering, came in contact with WaStop inline check valves through a presentation given by Eric Johansson. He could instantly see the reliability of the cone shaped membrane and felt that would be less prone to clogging than other check valves. He could also appreciate the low headloss and pulsating flow which would mean his pipes would empty quickly and debris would be kept away from the outlet.
Solution: 12 WaStop Inline Check Valves in stainless steel sized between NPS 8″ – 12″ (DN200-300)
Thanks to: Fischer Harris and Hancock Engineering.
Check valves protect Florida freshwater ecosystems
|(Article Published in World Water July/August 2016)
Marsh Landing, a residential community in northeast Florida, relies on Wapro check valves to prevent the Intracoastal Waterway’s brackish water from flooding and damaging freshwater ecosystems within stormwater retention ponds.
Marsh Landing, an elegant residential community in Ponte Vedra Beach, Florida, United States, uniquely integrates natural beauty and luxurious housing through careful land planning. Concern for nature and the environment has always been foremost in the community design of more than 1,000 single-family homes.
Building and infrastructure in coastal areas with natural elevations that range a mere 1 to 2 meters above sea level, however, possess challenges for stormwater management systems using ponds and wetlands; Marsh Landing
Major infrastructure improve- ments have been made over the past few years, and new projects for continuous improvement are being carried out, including a substantial investment to refurbish drainage and pump systems. These projects are being implemented to ensure that the ponds retain their useful- ness as stormwater retention structures and also as wetland breeding grounds.
Genesis Group, a US-based civil engineering, landscape architecture, and urban design consultancy, hired the US contractor CS3 to install approximately 100 WaStop inline check valves in order to protect these ponds and wetlands from brackish floodwaters.
Successfully maintaining a natural environment that contains wetlands and ponds woven into an active, vibrant community requires careful consideration. Nearly 100 inter- connected retention ponds drain into the Intracoastal Waterway and tidal tributaries. These ponds function as an integrated system to protect the community from stormwater flooding and limit the rate of drainage discharge, further protecting downstream property and watershed quality.
Salinity levels must be controlled to ensure that the ponds function as intended. Only a small increase in water salinity can cause a significant loss of biodiversity and alter the ways that the ecosystem functions. At high tide, the Intracoastal Waterway can fill these ponds with brackish water and reduce their intended design storage capacity, thus increasing the chance of community flood damage.
Additionally, salt water harms freshwater ecosystems surrounding these ponds and further shortens the life of reinforced concrete culverts and control structures. Salt water contains magnesium chloride, sulfate ions, and hydrogen carbonation ions that will essentially attack concrete to a certain degree, but what really starts to corrode in a concrete structure is its inner steel sub- structure. Because concrete is a type of porous material, oxygen and humidity can be present where the salt water comes into contact with the film that surrounds the reinforcing steel inside the concrete, initiating the corrosion process of the steel.
In their juvenile stages, fish are least tolerant to salinity, which potentially inhibits the reproduction of existing populations, and salt-averse species may be replaced by salt-tolerant species such as the three- and ten-spined stickleback in highly saline lakes. Macrophyte diversity may also decrease due to difficulties in plant germination, along with the success of a small number of salt-tolerant species.
Structures including outfall culverts, control works, pump discharge lines, and sluice gate controls have been put in place to control the outlet of the ponds to maintain water quality. Together, these structures maintain the freshwater ecosystems by preventing tidal inflow. WaStop inline check valves have been implemented within many of these structures as a backflow prevention device to ensure that flow can exit the ponds to maintain water levels. Additionally, the inline check valves prevent salt water from entering the ponds to ensure that salinity levels are also maintained.
Many of the WaStop installations in Marsh Landing are being retrofitted into existing structures. The WaStop inline check valve can be fitted horizontally or vertically and at either an inlet or an outlet of a structure; the valves are customized for easy installation without the need to rebuild the structures.
WaStop inline check valves are market leaders in low head loss, which means that the ponds can quickly drain water out to the canals during periods of high rainfall. This feature ensures that there is no upstream flooding, which in turn protects the surrounding residential properties, gardens, golf course, and other properties.
The valve works on differential pressure; it is completely closed and vapor-tight in its natural state. Flow in the right direction causes a pressure build-up against the membrane, which opens just enough to allow the liquid to flow unhindered. If the flow is reversed, the membrane fills with water or gas and acts as a stopper, blocking all backflow. When 100 percent closed, the valve stops all flow, thereby ensuring no area for growth of shellfish, which normally thrive in the transitional zone between salt water, brackish water, and fresh water. Consequently, the valves significantly lower maintenance costs and improve the system’s reliability.
Find out more at www.wapro.com
WaStop installation in Mönsterås – 15 years on …
|Mönsterås in Sweden was one of the early WaStop Inline Check Valve installations.
The issue faced was high sea levels during onshore winds. This caused the sea water to be forced up into the stormwater system, leading to back flow into the sewer system through the emergency overflow pipes. This in turn caused flooding in low lying houses upstream as well as surface flooding in low lying areas.
Two WaStop DN600 valves were installed in 2001 to prevent the sea water back flow. A flood bank was also built to prevent the sea level coming overland and causing surface flooding. Behind the WaStop valves a pump was installed to ensure that when high sea levels coincided with rain, the stormwater was still able to exit preventing surface flooding. The pump is automatic and starts when a specific level is reached.
The WaStop valves have been installed since 2001. They’ve been working perfectly with minimal maintenance and 100% functional operation time. This gives peace of mind for residents and the local council.
WASTOP PROTECTS Warsaw FROM the vistula
|The Vistula (Polish: Wisła) is the longest and largest river in Poland, at 1,047 kilometres (651 miles) in length. The drainage basin area of the Vistula is 194,424 km2 (75,068 sq mi), of which 168,699 km2 (65,135 sq mi) lies within Poland (splitting the country in half). The remainder is in Belarus, Ukraine and Slovakia.
The Vistula rises at Barania Góra in the south of Poland, 1,220 meters (4,000 ft) above sea level in the Silesian Beskids (western part of Carpathian Mountains), where it begins with the White Little Vistula (Biała Wisełka) and the Black Little Vistula (Czarna Wisełka). It then continues to flow over the vast Polish plains, passing several large Polish cities along its way, including Kraków, Sandomierz, Warsaw,Płock, Włocławek, Toruń, Bydgoszcz, Świecie, Grudziądz, Tczew and Gdańsk. It empties into the Vistula Lagoon (Zalew Wiślany) or directly into the Gdańsk Bay of the Baltic Sea with a delta and several branches (Leniwka, Przekop, Śmiała Wisła, Martwa Wisła, Nogatand Szkarpawa).
Large-scale floods in 2010 caused by heavy rain and rapid snowmelt in the mountains forced cities up and down the river to race to sandbag streets and buildings along its banks. In Krakow, the mayor declared a state of emergency after the river passed the high-water mark at 74 cm above average. The next day the river swelled to 300 cm above flood stage. The massive stone bulwarks lining the river held firm, though, and channelled most of the problem past the city and downstream to other cities, which suffered inundation. In some cases the water clearly revealed the naivety of local officials who had allowed wide development in the now soaked flood plains. About a month after wave upon wave had passed, Warsaw and the other cities dried out and returned to normal and the tamer river continued flowing, almost acting as if nothing had happened.
There are many stormwater outfall into the river which become channels for backflow during flooded river conditions. The flooded river pushes water back up the stormwater pipes leading the water directly into the suburbs. Instead of the stormwater pipes leading water to the river the exact opposite occurs which causes massive flooding.
Installing a WaStop on the outfall effectively prevents any flood waters entering the stormwater pipe and therefore stops flooding. The stormwater is still able to be released into the river but river water is kept off the streets and out of the houses in the surrounding areas.
Another successful installation with hundreds of people now protected against flooding. Thanks to our distributor in Poland, Rafnar.
Five large wastop protect Osijek, Croatia
|The Drava River is one of the five largest tributaries of the Danube River, and flows through five different countries to its mouth downstream of Osijek. The Drava’s main tributary is the Mura River, and the two meet in Croatia to form a unique natural river mouth. The river has a history of flooding and causing extensive damage to the surrounding towns and farms. In an effort to mitigate the flooding in Osijek 5 WaStop Inline Check Valves have been installed. Three DN 1000 (NPS 40″) and two DN1500 (NPS 64″). These installations prevent back flow from the river into stormwater outfalls when the river is in flood conditions.
These 5 installations give peace of mind to the inhabitants that have lived with flooding for centuries and will protect future generations.
DN600 WaStop protects from flooding in Depew NY
ACE INSTALLS UKS BIGGEST WASTOP CHECK VALVE IN POOLE
The area around Poole harbour is well known as a tourist hot spot attracting over 3 million visitors a year but the shallow waters can also pose problems for flood defence.
One identified problem was an outfall near Sterte. This had previously used a steel 1.5m flap valve. This large outfall had a comparably small head pressure causing water to back the culvert. The decision was taken to fit a 1.5m Wastop with a custom flange plate to form a tight seat to the existing civil structure. The 1.5m valve supplied for this site is the largest WaStop check valve to be installed in the UK and one of the largest to be installed in the world.
The installation was complete with the addition of debris screen to prevent the build-up of rocks thrown up by turbulent waters. Previously when a flap valve had been installed it was impossible fit a debris screen as it would block the valve from opening. The design of the WaStop allows it to fit inside the outfall itself meaning that the debris screen does interfere with its operation. One of the widely recognised selling points of the WaStop valve is it pulsing motion. This characteristic forms a natural flushing action clearing silt and debris from the valve and the screen so that operation is not restricted.
Over the last few years ACE has seen an increasing demand for the WaStop Check Valve as its unique design has found a home in greater and greater diversity of sites.
UKs biggest WaStop Check Valve was installed in Poole
WaStop Protects Beautiful Town Square in Rivergaro, Italy
Rivergaro town square recently underwent renovation to give the townspeople a beautiful place to meet and enjoy the local fare.
The river Trebbia runs close by the square, and has, throughout the course of history, caused numerous floods in the original town square. During the design phase of the town square the local authorities in Rivergaro promised to develop a system to prevent that the public space becomes inundated during high water levels in the river. During the most recent flood of September 2015 shops, basements and businesses suffered major flooding due to backflow from the river through the storm water drainage pipes.
To alleviate this problem, it was decided to invest in flood protection. Four WaStop in sizes from DN600-DN800 were to be installed to protect Piazza Paolo and Meucci areas. WaStop was the valve of choice given that the valve is closed and protecting the city in is normal state, whilst allowing stormwater to exit the system on demand.
“These installations are a blessing for us, a necessary and important intervention” says the Deputy Mayor Mauro Rai. “We cannot say we are out of danger during floods but now we at least don’t have to worry about the Trebbia River. We created this beautiful square from an aesthetic point of view but also put great emphasis into making it secure, preventing the square from flooding again. The installation of these valves is one of many hidden jobs that are not visible to the public but which are invaluable.”
Shortly after installation the WaStop Inline Check Valves were put to the test, and provided 100% flood protection giving peace of mind to the local authorities, as well as the residents.
Thanks to Euronova for the information surrounding this installation.
Wastop installed in Rivergaro to protect the
WaStop prevents flooded roads in Carolina Beach. Holding back the flood.
Carolina Beach is a seaside destination in North Carolina, USA, known for its colorful, vintage charm. Climate change affects sea side towns and properties dramatically. In Carolina Beach the townspeople have dealt with flooded roads caused by high lunar tides for many years. They were used to the blocked roads, wet pavements, grass killed off by salt water. All an effect of lunar tides filling the storm water system and catch basins, which eventually overflow onto the streets. The maintenance crew at Carolina Beach regularly placed ‘Road Blocked’ signs and waited patiently for the tide to recede. Investing in a permanent solution to this problem was pushed up the priority list. Solving the problem would save maintenance resources, and effectively allow allocation of those resources to areas where a solution couldn’t be found. Solving the problem would also increase peace of mind for residents.
We at Wapro know why providing an effective solution is important. In this instance, we recommended an 18” WaStop Inline Check Valve which was installed easily into the existing pipe. Unlike any other check valve available today, Wastop can be mounted horizontally, vertically, on an inlet, outlet, in a chamber, or utilizing flanges making it a simple and safe solution for backflow and flooding problems.
Wapro’s engineers have worked in the field and know that a quick, easy, secure installation is essential. Carolina Beach could install the WaStop in minutes by simply bolting the WaStop onto the existing headwall. No construction work, no alterations.
Carolina Beach can focus on being an enjoyable vacation destination without the shadow of potential flooding thanks to WaStop.
Roads in Carolina Beach closed due to high tide flooding.
WaStop successfully installed in Kristinestad, Finland
Kristinestad in Finland suffered significant flood damage at high tides in a river during the fall of 2013 and the spring of 2014. During this time, around eighty buildings were water damaged due to flooding. The damages amounted to about 1.5-2 million euro.
To avoid back flow from the river at high tide, WaStop check valve was installed in the drainage pipes leading out from the properties.
The project proved successful and the areas of Kristinestad protected with WaStop have peace of mind knowing that they won’t be flooded again.
In the spring of 2016 phase two of the project began with more WaStops being installed to protect other areas against flooding.
In February 2017 Wapro visited Kristinestad for an inspection of the already installed WaStop check valves. During the visit, it was clear that the valves are protecting the area as expected and giving peace of mind. The next stage in this project will progress during 2017.
WaStop installed in a river in Kristinestad.