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  • Writer's pictureIn-Pipe Technology

The Types Of Sewer Systems And What They Do

Sewer systems are an essential part of our daily infrastructure, keeping us safe from pollution and disease by safely transporting untreated sewage to wastewater treatment centers.

The problem comes in when they stop working. Blockages due to fats, oils, and grease (known as FOG) or non-flushable materials cause back-ups that can cause raw sewage to spill over into residential or commercial areas and horrendous smells too. It can also drive up costs as local municipalities have to fork out more and more money to resolve the issue.

The most common reason for this is that there is a lack of education into how our sewer systems work and how we as individuals can ensure that we are not doing more damage. If we do our part to prevent non-suitable materials from going down our drains, we can ensure that our infrastructure works as it should with no smelly surprises.

There are several types of sewer systems used today, and they all have distinct use-cases. In this guide, we’ll go over the different kinds, how they work and how to do your part, and ensure you are doing your part to prevent any blockages or build-ups.

Type 1: Combined Sewers

The first type of sewer we’ll be discussing are combined sewers. These are not necessarily used as often in areas that have heavy rainfall, but they are still present in some municipalities. Let’s talk about why:

Combined sewers use a single-pipe system to carry a combination of wastewater and stormwater runoff to wastewater treatment plants. The reason this system isn’t as compatible with rainy areas is that when there is a lot of surface water paired with sewage water, the system can easily overflow.

In wet weather, the combined sewer system might not be able to direct all of the flow to the wastewater treatment plant as it is supposed to. This means that more of the runoff will go back into groundwater sources without having proper treatment first, which can have devastating effects on the natural environment and our drinking water sources.

Combined sewers can also cause an issue even if the flow is kept towards the wastewater treatment plant. Overflow events can precipitate an abundance of untreated wastewater to reach the plant which can overwhelm the systems and imbalances in treatment levels.

Type 2: Separate Systems

In type 2, we see more than one set of sewer lines being a connection between the source of sewage and the wastewater treatment plants. One is connected for sanitary sewage, while the other is used only to process stormwater or runoff rainwater.

The major difference here is that the sewage-related to sanitation is pushed directly to the wastewater treatment plant, while the rainwater is carried directly to a natural water source like a local river.

There are several reasons why this approach is considered to be more advantageous. The first is that the load on the system is less overall because the stormwater is separated from the sewage.

It’s also more financially viable for the plant to only treat the wastewater that needs it versus the rainwater which can typically be discharged into the environment without causing ecological damage.

But there are disadvantages to separate systems that need to be dealt with too. Smaller sewers mean cleaning blockages can be more complicated, and material build-up will require repairs to be done. With two sets of sewers to deal with, this can quickly become expensive.

Another thing to keep in mind is that separate stormwater drains are only really fully used during times when there is a lot of rainfall. In the drier seasons, these collection systems can easily become a dumping place for garbage and other non-suitable materials which will require clearing.

More On Dedicated Sanitation Sewers

Sanitation sewers are the sewers we rely on to remove untreated sewage from our businesses or residential homes. They form part of an infrastructure made up of piping, vents, pumping stations, and much more with the overall goal of ensuring our water quality remains good.

When you flush or wash old dishwater down the drain, the contaminated water travels through small pipes from your home or business into either the sewer main or into a septic collection system.

From there the untreated sewage is pushed further down the system to the wastewater treatment plant where it undergoes several treatment steps to remove contaminants. These processes include manual filtering for larger non-soluble objects and chemical or UV-light treatments to remove pollutants at the microbe level.

After being tested a final time, the now-treated water can be safely released back into the environment where it will cause no damage to the local ecology.

What You Can Do At Home To Support Sanitation Sewer Health

The best thing you can do at home or in your business to ensure that the sanitation sewers in your area remain clear of blockages and health risks is to be aware of what you put into your drains.

Several household products are not flushable, for example, despite what they might say on the packaging. Wet wipes and sanitary products are one of the biggest causes of concern coming from residential areas.

Another thing to keep in mind is that you should be cautious not to put any FOG materials down your drain. Things like cooking oils that are washed down the drain can cause a build-up inside the pipe or other issues like bad smells.

What You Can Do At Home To Support Storm Sewer Health

Storm sewers also need individuals to do their part to avoid overflows and other issues that can affect groundwater and the soil.

What you can do to ensure that storm sewers remain blockage-free and functioning is to check that no hazardous waste or non-suitable materials are being collected. Things like paints, oils, and other runoff materials should never be present in this collection system since they will be transported directly to natural water sources and cause damage to local wildlife.

If you notice the storm sewer close to your home or business is getting clogged with things like leaves or litter, you should make sure to safely clear it away to prevent overflow during heavy rain. If you become aware that dangerous chemicals are in the storm sewer, you should contact your local government or EPA office to report it as soon as possible.

How In-Pipe’s Custom Solutions Protects Communities

The sewer collection system is effectively a large bioreactor.

Put this underutilized part of your infrastructure to work by supercharging the biological reactions that are already happening there using a custom nutrient removal solution from In-Pipe.

Start breaking down the organics before the waste stream enters the plant. Being out of balance is not a healthy long-term condition. That’s when regulators with weeks or months of negative data might stop by to discuss your permit status and when local leaders start asking questions and challenging your expertise because they worry the plant’s problems are making them look bad.

Use its retention time to grow large amounts of beneficial bacteria that reinforce the microbial community at the treatment plant responsible for removing harmful nutrients.

In-Pipe can also assist with FOG and odor control.

While much of the waste that enters the system travels through sewer pipes to your plant, some bacteria get left behind and form a biofilm. As this biofilm builds up, the bacteria that populate it grab nutrients as they pass by, and they keep producing H2S which makes its way – in both liquid and gas form – all the way down the pipe, into the lift station, the treatment plant, and even the lagoon, if you have one. This is ultimately where bad odors come from.

Instead of finding a permanent solution for this constant problem, most wastewater professionals deploy an array of chemicals and equipment to try to remove the odor after it has formed. Odor problems can occur in multiple areas in the process, but if you attack the problems at the point where they germinate you’ll have much better success at preventing issues later in the system.

In-Pipe Technology’s solution is designed to fight fire with fire, eliminating odor problems at their source with a proven bioscience solution that targets the cause of the odor and destroys it.

If odor-causing bacteria are stuck inside a pipe, they likely have plenty of nutrients to keep it going. To combat this, In-Pipe will continually dose its proprietary mix of bacteria into the affected area, which will get to the nutrients three times as fast to effectively starve the bad bacteria. The result is that the odor-creating bacteria die off and dissolve into the wastewater.

Don’t get caught having to deal with these issues by the time they are already causing hazardous health and safety issues. Invest in a solution that has been proven to work in various cities across the US.

Contact us today to learn more about our custom solutions and what we can do to help you build a safer, happier environment here.

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