Cistern Cleaning Services Near Me? All Answers

In many areas of the world, people get their drinking water from collection systems that collect and store rainwater. Even when properly constructed and used, these systems can easily become contaminated with germs that can cause disease. Some water supply systems use surfaces such as roofs to collect water and direct it to a cistern (storage tank).

Floods and heavy rains can flush large amounts of debris and contaminants into cisterns and rainwater collection systems, contaminating drinking water. If cisterns and similar systems come into contact with flood water, you must assume that your drinking water is contaminated. If you are concerned about contaminating your drinking water source, please see Disinfecting Cisterns and Other Rain Collection Systems. Advice on cleaning storage tanks or tankers can also be found in the World Health Organization’s step-by-step guide to emergency cleaning and disinfection of water storage tanks and tankers [PDF – 4 pages].

If you don’t get your water from a cistern or well, see Prepare for emergency water supply for information on disinfecting your water.

IMPORTANT: Disinfection will not make water contaminated with fuel or toxic chemicals safe. Do not enter the cistern. Gases and vapors can accumulate and create a hazardous environment.

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When it comes to cleaning your toilet, the flush tank is often overlooked. That’s mostly because not much attention is paid to limescale in a toilet tank, rather than keeping the pan and exterior clean. But it’s always good practice to descale a toilet tank regularly to keep it running efficiently. How to clean a toilet cistern.

The best way to remove limescale in a toilet tank is to leave the solution on for up to 12 hours. This gives it enough time to break down deposits and makes cleaning easier.

You need: protective gloves

Old clothes

brush

cleaning solution (citric acid or vinegar)

water

Vinegar

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Removing Scale from a Toilet Cistern In the long run, knowing how to descale a toilet cistern can extend the life and efficiency of your toilet, so it’s worth doing. And once you learn how to remove scale from a toilet tank, it will be easier next time. Follow this step-by-step guide for great results. Wear protective gloves and old clothes Put on protective gloves and old clothes before you start self-protection. Remove the lid from your toilet cistern. Remove the lid from your toilet cistern to start cleaning. Lower the water level Lower the water level – either by turning off the water supply to the toilet or by adjusting the float level valve. Pour a cleaning solution into your toilet tank and let it sit for at least half an hour. You can use a specialty cleaner like citric acid, or try vinegar if you want a more natural approach. Make sure the solution covers the limescale and leave it on for at least half an hour (or longer if you can). Scrub thoroughly with a brush. Scrub thoroughly, rinse and repeat if needed. It’s a good idea to descale a toilet tank weekly to prevent scale build-up again.

How to clean a toilet tank after descaling Once you have removed the scale, you can proceed to cleaning the tank itself. This will help get rid of bacteria and remove unpleasant odors. Cleaning your toilet tank follows a similar schedule to descaling, but shouldn’t take as long. Make a Vinegar/Water Solution Make a mixture of three parts vinegar and one part water. Scrub the marked areas before applying the solution. Pour them into a spray bottle and aim at the marked areas. Scrub them first before working on the rest of the toilet tank. For stubborn stains, fill the tank and leave the solution on for 10 minutes. If you come across really stubborn stains, you can fill up the tank. Leave the solution on for about 10 minutes before scrubbing to remove dirt and grime. Flush solution and top up with cold water Flush solution and then top up with cold water. Rinse everything out and refill the cistern. Flush again to flush everything out, then refill the cistern.

The survey What brand of dishwashing tablets do you usually buy? Fairy 0% Ecover 0% Finish 0% Smol 0% I buy the cheapest 0% 0 Votes

There you have it, an easy-to-follow guide to cleaning and descaling a toilet cistern. If you did it the first time, next time will be really easy. With regular cleaning, you can keep your toilet in good condition and ensure it performs well over the long term.

Cleaning your toilet is a necessity, and while cleaning the bowl itself is fairly easy, you may be overlooking another important part of these toiletries: the toilet tank. Part of your regular cleaning routine is wiping down the outside, but taking care of the inside of the tank is just as important to the long-term maintenance of the light. “While the water in the tank is typically clean, the metal parts can corrode and rust, and the inside of the tank can become discolored,” says Patty Stoffelen, bathroom fixtures dealer at The Home Depot. “Cleaning your toilet flushes will help prevent rust and mold from forming.”

modern bathroom with blue tiles Credit: gan chaonan / Getty Images

Preparing to clean the toilet tank

Although cleaning the toilet tank is a little more involved than cleaning the outside, it doesn’t have to be as frequent; Stoffel recommends only adding this work to your list “once or twice a year for upkeep.” Gather a few basic items: “We recommend using a scrubbing brush ($11.99 for a set of four, amazon.com) in combination with a bathroom hard-surface sanitizer formulated without bleach,” says Stoffelen. “The biggest no-go when it comes to flushing toilets is bleach – do not use bleach or products that contain bleach in the sink as it can damage the internal parts of your toilet. If you want to remove stubborn stains from the kitchen sink, I also recommend white vinegar diluted with water.”

How to clean the toilet tank

Manual cleaning consists of two main elements: soaking the tank to remove stains and scrubbing the tank and parts to remove accumulated dirt. You can do both first; Molly Maid President Vera Peterson begins soaking the tank. “First remove the lid and take a look inside,” she says. “If you see mineral buildup or dirt, pour four cups of vinegar into the tank. Let this soak for up to an hour.”

Before scrubbing, empty the tank. “Start by turning off the water supply valve, which is either behind the toilet on the wall or on the floor,” says Stoffelen. “Then you should flush the toilet until the tank is empty. You can use a sponge to remove the remaining water at the bottom of the tank. To remove general dirt and grime, spray the inside of the tank thoroughly with a bleach-free disinfectant and allow the disinfectant to sit for 15 minutes. Clean the tank with a scrub brush and wipe the tank’s internals with paper towels.” Stoffel adds enough vinegar diluted with water to fill the empty tank up to the overflow valve and lets it sit for up to 12 hours; keep this in mind Note that if you flush during this time, you will drain the tank of its stain control solution, so you should encourage your family to use the spare bath while the tank is soaking.

Hello – I have a cistern that I would like to use for drinking water. Our well has been pumping very little water lately and I am using…

Keeping the inside of your water tank clean is especially important if you use the water for drinking. Aside from health issues, clean tanks also save on filter cleaning or replacement and water pump failures. Sludge is a common problem for water tanks, but there are things you can do to minimize, bypass, or remove it. Read on to learn more about mud and what you can do about it.

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What is mud?

Even if you have a strainer installed, sometimes organic matter can collect at the bottom of your water tank. Plant matter, sediment, and other debris sink to the bottom and begin to break down, creating a thick layer of mud. This sludge mostly consists of contaminants such as dirt, leaves, paint chips, insects, etc. and is not necessarily a health issue. However, it can cause problems for filters and pumps on equipment.

While your water tank usually contains many types of bacteria that are not harmful, there are some types that can cause health problems.

As this sludge contaminates your water, it can become the perfect environment for harmful bacteria like E-Coli and Campylobacter to proliferate. These bacteria need to be monitored or filtered out as they can make you or your family members sick.

What can I do to reduce sludge in my tank?

Prevention is better than cure when it comes to mud in a tank. To reduce sludge, you must first consider where it is coming from.

When you collect water from a roof, it means that the water runoff will bring with it dust that has settled on the roof and wash in bird droppings or rodents or animals that climb a roof. Leaves, dirt or chipped paint or even insects also contribute to the sludge in your tank.

Without taking some preventative measures, your tank is almost guaranteed to build up a layer of sludge on the bottom of the tank. Simple steps like removing overhanging branches from your roof, removing animal access to your roof, and keeping your gutters clean are the best start to reducing the amount of mud buildup.

Other steps to take include installing leaf guards on downspouts or leaf guards on gutters. Cover the inlet and overflow of your tank with netting to prevent birds, animals and insects from having direct access to the water.

Having two tanks gives you another benefit as you can have a settling tank system. This means you use the tanks in a row, with the first tank receiving the first rain, allowing sediment to settle to the bottom of that tank. The water from the first tank must then flow or be pumped into the second tank; however, do not scoop the water from the bottom of the first tank. The bottom of the first tank will be where the sludge settles.

When using a pump, a floating inlet draws the best quality water from 200mm below the water surface, which also prevents the pump from drawing a free surface vortex that could easily suck air into the pump.

If you have two water tanks, most of the sludge will be in the first tank, meaning only one tank needs to be cleaned. The first tank would be more suitable for the garden, while the second is better for washing machines and drinking.

Can I remove mud by hand?

Cleaning a tank by hand is possible, but it can also be a time-consuming job. You can drain the water from the tank, hose down and sweep the floor. That way you can be sure you’ll get all the mud, but emptying the tank and getting in can be dangerous or difficult.

You could also get a rainwater pump for cleaning that will suck up the mud. However, this can be expensive if you only clean your tank every few years. It often just makes sense to pay a company to clean your tank, although this too can be costly.

Related topic:

Water tank cost and price guide

Remember that the inside of a tank is a confined space with little ventilation. Be sure to work safely in such tight spaces. If you need to clean your tank, consider hiring a professional tank cleaning service to stay safe.

What is a water tank self-cleaning system?

Another option is a self-cleaning system like a tankvac, which automatically removes any debris or contaminants as soon as they enter the water. Once you have such a system installed, you no longer have to worry about it, so you don’t have to constantly clean your tank or worry about contamination.

When you install a self-cleaning system, you attach a special pipe to the bottom of your tank that creates a vacuum that sucks out poor-quality sewage and harmful sludge.

How do I know if the sludge in my tank is harmful?

You should check your outside roof, gutter and tank every 6 months or less. It’s also a good idea to inspect the inside of your tank every 2-3 years and remove any accumulated sludge.

Over time, you can build up low levels of immunity to some microbes. If your tank isn’t cleaned regularly, you can reach a level where it becomes a huge health hazard. People experience diarrhea, vomiting, stomach cramps, cold sweats, dehydration and even death.

Water testing can give you an indication of the condition of your water, but only at the point of withdrawal. Water quality can change rapidly depending on temperature, rainfall, and the seasonal behavior of birds and animals.

Microbes and bacteria multiply in water by dividing in half. Depending on the temperature and type, this process can take up to 20 minutes. This makes the water smell like the gas given off by bacteria. The water can also thicken, which is caused by their large numbers as the bacteria multiply quickly.

If contamination is found or suspected, remove the contamination and disinfect your aquarium water with an appropriate dose of unstabilized chlorine (approximately 5 milligrams per liter). Chlorine testing should be performed using an appropriate kit.

If you use your water tank for drinking, it’s safest to install a filtration system between your tank and your drinking faucet. The appropriate filtration system prevents any contamination or bacteria that you may miss between inspections.

For more water tank tips, contact us today.

This article aims to provide helpful information on the topic covered. It is not intended to replace recommendations from a qualified physician.

If you really want to get your toilet tank clean, you need to make sure you have the right cleaning products for the job. Vinegar is a great toilet cleaning solution. Not only is it chemical-free and naturally antibacterial, it’s also acidic, helping to remove minor limescale and limescale deposits. All you have to do is pour a few cups of vinegar into your tank and let it sit for about an hour, then scrub and rinse to flush it out. But if you feel like something isn’t clean, unless the chemical fumes are burning your nose, then bleach is a good choice. It’s a great disinfectant and will remove mold but it won’t affect limescale so you’ll need to use an acidic cleaner that’s safe for use on porcelain.

If you have some stubborn stains that need a little extra elbow grease, you really need to get in the tank. If you don’t want to dip your hands in this water, you need to drain the tank. All you have to do is turn off the water supply, usually somewhere down the toilet, and flush the toilet before you start scrubbing. You’ll probably find that cleaners work a little better and faster when not diluted with water; This also applies to the inside of the bowl. However, be aware that chemical cleaning agents can attack the rubber flap, which can eventually lead to leaks. So when you’re down there, be sure to check that your flapper is still in good condition.

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Water is one of the basic requirements of life, so there is no supplement or substitute for water. I think we take water for granted sometimes, and that would become apparent if you are ever without fresh drinking water. Getting thirsty is not a pleasant experience, especially extreme thirst. When I was looking at our water storage tank the other day, I couldn’t help but wonder, “How long can water be stored before it goes bad?”

The safe storage of drinking water ranges from one day to indefinitely, depending on how you store the water and the level of purity of the water. Clean water left outside in an open cup is likely to go bad (contaminated) within 1-3 days. Water from your faucet (provided it’s clean enough to drink) stored in a sealed container can last up to 6 months or maybe longer, but it may be a good idea to check and add a small amount of household chlorine bleach to purify the water (do not use bleach with refreshment or fragrance). Purified water sealed in a food safe container lasts a long time, 2 years or even much longer.

The estimated amount of time before clean water goes bad (becomes contaminated)

Type of water storage Time to contamination Open cup 1-3 days Self-sealed containers, barrels, kegs or jugs of clean tap water 6-12 months + (check and replace regularly) Purified water sealed in a food-grade container 2 years + (when stored properly )

How long can you store water in a 55 gallon keg?

Drinking water stored in a 55 gallon food grade keg can be safely stored for up to 1 year or even longer under the right circumstances. To safely store water in a 55 gallon keg or keg for 1 year or more, a clean food grade keg must be used, tightly sealed to keep light and chemicals out, in a dark, cool place and away from concrete are preserved. and not improperly accessed. Additionally, with regular treatment (about every 6 months) with the right amount of household chlorine bleach or a water conditioner, it can be stored for much longer. However, if possible, I always replace my stored water every year.

Does stored water go bad?

When stored properly, water does not spoil. The pollution that seeps into it actually makes the water go bad. In theory, your water could stay good forever if you take the right precautions by sealing and storing your water so bacteria or other contaminants don’t get in and spoil it.

Let’s clear up something small real quick. Water itself doesn’t really go bad. The truth is that it can and does become contaminated over time. Bacteria, algae and other pathogens are often what contaminates the water reservoir and causes it to “actually go bad”. This contamination can come in many different ways with varying degrees of severity.

Can water be stored indefinitely?

Drinking water can be kept indefinitely when properly stored in food grade containers stored in a dark, cool environment. Chemical treatments (including household bleach or iodine) can be used every 6 months to a year to keep the water drinkable. However, it is a good practice to drain the water reservoir, clean the containers and replace them with new drinking water about every two years or sooner.

Containers, including food-grade plastic containers, release chemicals into water storage but do not cause serious health problems. However, if left in a hot environment like a garage or car during the summer, the water will not taste very good and will be at a higher risk of contamination.

How to store water to prevent it from going bad

The Federal Emergency Management Agency (FEMA) recommends storing tap water in clean plastic, glass, enameled metal, or fiberglass containers. After filling the container, it should be tightly closed and stored in a dark, cool place.

Water storage conditions to keep it from going bad include:

Start with clean drinking water

Store in clean food-safe plastic, glass, enameled metal, or fiberglass containers

Close container tightly to keep light and chemicals out (covering the water storage tank with a tarp might be a good idea)

Store away from concrete, chemicals, or anything you don’t want to leach into the water and keep in a dark, cool place

How can you tell if your water has gone bad (contaminated)?

Your water reservoir may be contaminated if

It has a strange smell

Is cloudy

Develops a strange color

Green algae grow in it

Has floats

Consciously make your best judgment. Inspect your water reservoir about every 6 months to determine if it should be treated or replaced. Once you are sure, it is best to dump out the old water, clean the container and fill with clean water.

Use a water filter

Contaminated stored water can be cleaned and made potable again. I always keep some new water purifiers on hand for emergencies. If I’m unsure of the purity of my water reservoir, I will definitely use a water conditioner or water purification method before drinking. I always keep a small water filter straw and a larger water purifier on hand just in case. In the go bag and at home. It can be helpful in an emergency and you are unsure whether your water storage is contaminated or not.

It can be difficult to know which water filter to get, so read Choosing the Best Emergency Water Filter: Buying Guide.

I use a water filter when drinking from my water reservoir when I’m unsure if the water is contaminated. I keep several of the following water filters in different locations for easy access when needed.

By far my favorite mini water filter straw is the Sawer Mini Straw (check price on Amazon). It’s better than the Life Straw because it filters up to 100,000 gallons of water and the Life Straw only filters up to 1,000 gallons of water. I also own a couple of Survivor Filter Pro – hand pump water filters (check price on Amazon). I like this hand pump filter best for water storage because I can just drop the receiving inlet hose into my water storage tank and pump out clean water without moving, tipping, or putting my hand in the tank.

Can you get sick from drinking old water?

You can get sick if you drink stale water. However, the reason for the disease is not that the water is old, but that bacteria, algae and other pathogens get into the water source. So if you get sick from drinking old water, it depends more on how the water was stored and how clean it was than how old it is.

For example, you’re far more likely to get sick from drinking old water that’s sat outside in an open cup or bottle for a few days than from drinking a sealed, unopened bottle of purified water that’s a few years old.

3 Ways Water Reservoirs Go Bad (Become Contaminated)

Bacteria or algae were originally in the water before being stored in a container. Impurities were washed out of the tank into the water reservoir. Improper access to the water reservoir

bacteria or algae

Is your water reservoir green, smells funny, or has floats? Your water reservoir may be contaminated. Water contaminated with bacteria or algae is easy to spot when the water has been stagnant for a few weeks. For example, if you leave a bucket of water outside for a few days, you would find that the water in the bucket contains mosquito larvae, algae, and various other life forms that you don’t want to drink from.

Impurities are washed out of the container into the water reservoir

The second way to make your water reservoir unsafe to drink is if something gets into the water from the reservoir. For example, if you stored water in a lead container, it would seep into the water and make it toxic. It is important not to store water in containers that are not food safe. The reason it’s so important to use food-grade containers is that some containers (like lead or an old container of pesticide that hasn’t been cleaned properly) are actually releasing toxic chemicals into your water storage, which is the cause of contamination will be. According to the CDC (Centers for Disease Control and Prevention), clean drinking water should preferably be stored in plastic, ceramic or metal containers.

Improper access to the water reservoir

The third way your water storage can become contaminated and go bad is by sticking your hands or other objects that might harbor bacteria into your water to access it. The CDC suggests that your containers have the following characteristics:

A small opening with a lid or cover that prevents users from placing potentially contaminated objects, such as hands, cups, or ladles, in the stored water;

A tap or small opening to allow easy and safe access to water without having to insert hands or objects into the container; and,

Size adapted to the usual household water treatment process with permanently attached instructions for use of the treatment process and for cleaning the container.

Teach all family members how to properly access your water storage. Be careful and don’t be the cause of your water storage becoming contaminated and going bad.

Disinfection of water reservoirs

If your water reservoir isn’t green and has algae growing or if it doesn’t smell really bad, you can just disinfect it. It’s important to remember to clean your water reservoir regularly. A good way to disinfect your water reservoir is to use bleach.

How Much Bleach Should You Add to Drinking Water?

Add 8 drops (⅛ teaspoons) of liquid household bleach per 1 gallon of plain water

Add 16 drops (¼ teaspoon) of liquid household bleach per 1 gallon of cloudy water

Clear water

According to the CDC (Centers for Disease Control and Prevention), add 1/8 teaspoon (8 drops, or about 0.75 milliliters) of liquid household bleach to 1 gallon (16 cups) of plain water.

Muddy water

The CDC also suggests adding 1/4 teaspoon (16 drops, or 1.5 milliliters) of household liquid bleach to 1 gallon (16 cups) of cloudy water.

*Treating water with household bleach containing 5.25-8.25 percent chlorine

*Do not use bleach with fresheners or fragrances.

This chart shows how much bleach is needed to clean/sanitize 1,000 gallons, 300 gallons, 275 gallons, 50-55 gallons, and 1 gallon of water.

Amount of water 1,000 gallons 300 gallons 275 gallons 50 – 55 gallons 1 gallon Clear water bleach 2 & 1/2 cups 3/4 cup 2/3 cup 2 tablespoons & 1 teaspoon 8 drops Cloudy water bleach 5 cups 1 & 1/2 cups 1 & 1/3 cups 5

tablespoons 16 drops

Water retention that lasts longer

An easy way to store water is to buy purified drinking water in plastic gallon jugs at the grocery store. This water is inexpensive, free from bacterial contamination and sealed in a food-safe container. You can store this water indefinitely, but make sure you check it regularly in case the container wears out or has some kind of breakage.

Another option is to buy bottled water, which should last for years, just like the gallon jugs mentioned above. I find it useful to store drinking water for at least 2 weeks in store-bought water bottles, which I drink and rotate daily.

Regularly clean your old water storage tanks

It’s always a good idea to clean a new water tank or container before storing clean water in it. In addition, it would be advisable to regularly clean old water storage tanks. You can use the old water in your garden or something useful and fill in new clean water after cleaning the tank.

The CDC suggests you use these steps to clean and disinfect water storage tanks:

Wash the reservoir and rinse it completely with water. Disinfect the container with a solution made by mixing 1 teaspoon of unscented liquid household chlorine bleach in a quart of water. Cover the container tightly and shake well. Make sure the sanitizing bleach solution touches all interior surfaces of the container. Wait at least 30 seconds and then pour out the sanitizing solution from the container. Allow empty sanitized container to air dry before use OR rinse empty container with clean, safe water already available. Pour clean water into the disinfected container and cover with a tight lid.

Conclusion

It is so important to know how long you can store water in different types of containers and under different circumstances. Water is such an important and neglected commodity that we should all save to sustain our family’s life in case of an unforeseen emergency. I hope this article has been helpful and encourage you all to save water for each family member for at least 2 weeks. Much luck!

Looking for help getting started with food and water storage? Check out EZ-Prepping’s water storage calculator and our food storage calculator!

Changes in traditional stormwater management practices are underway and regulators are implementing new guidelines and requirements for Low Impact Development (LID). The new rules focus on strategies to reduce runoff, including reduced sealed area and on-site infiltration. These options can be difficult to implement and are not practical in every situation. Engineers, architects and developers are designing rainwater harvesting (RWH) systems as an alternative LID practice to keep water on site and reduce runoff. Compliance with runoff reduction requirements is a compelling economic benefit for developers to justify a RWH system that would otherwise be excluded from consideration despite the environmental benefits. With the benefit of runoff reduction as its primary justification, the project is able to capture the additional benefits of LEED credits, reduced utility bills and reduced demand for municipal water systems.

RWH does not have a long history of use in modern site design, but now that it is an interesting subject many engineers and architects need to learn this multifaceted new practice. A previous CE News Professional Development Series article discussed common system components and common design requirements. This article focuses on the most central – and in many cases most expensive – component of the system: the cistern.

Basic cistern components

Cisterns come in all shapes and sizes, but there are basic characteristics that should be present in every cistern, regardless of which type is chosen (see Figure 1). The most common items to specify include the following:

Watertightness Rating – Vessels designed to hold water should be able to maintain a minimum watertightness rating for the life of the cistern. Since almost all systems are open to the atmosphere, passive head pressure is usually equal to depth. In most cases, it’s only a few pounds per square inch (psi). Tall, above-ground cisterns are the exception where 10-15 psi can be more common. Testing to ensure watertightness can be difficult on large systems, so a factory test or production standard may be the best specification requirement to ensure watertightness of the system as delivered.

Legal Requirements – Many state plumbing codes require two important elements in a cistern designed to improve water quality. The first is a stilling inlet which creates a full pipe flow within the inlet pipe and drains the incoming water from the bottom of the cistern to the top. This reduces turbulence and the potential for interfering solids that have settled to the bottom of the cistern. The second common requirement is a floating outlet. The suction hose to the pump should be flexible with an inlet strainer attached to block gross contaminants. The hose should be connected to a float so the inlet is never all the way down in the tank where solids could be sucked into the pump. It should also never be on the surface where fine floating matter may be present. The float should be suspended in the water column to ensure the cleanest water within the cistern is withdrawn. This improves the quality of the reuse water. Cisterns should also have an overflow path, vents, and screens or water traps over the inlets and outlets to prevent insect and animal access.

Pump Types and Location – There are many options for configuring pumps. Submersible pumps placed directly in the cistern or in a downstream wet well are powerful options for higher head applications, but must be hardwired to power in the cistern. Suction pumps placed above ground are also common, but are limited by depth and pressure. In many cases, a low-pressure suction pump is connected to the cistern with an additional pressure booster pump in building services.

Access and maintenance – RWH systems can have a lifespan of 20 to 50 years or even longer. Although all systems should include pre-treatment, when millions of gallons of water flow through a commercial-size system, sediment accumulates over the years. All cisterns should be equipped with multiple access points to aid in pump maintenance, inspection, repair and cleaning.

Cistern Placement: Above Ground or Below Ground?

Cistern placement is a compromise decision unique to each site, and there are many pros and cons of above-ground and below-ground configurations.

Above ground systems can be an attractive design element for a project and do not require excavation. Their size is usually limited to 10,000 to 15,000 gallons unless there is room for a large footprint or multiple cisterns. They may also need to be taken offline in cold weather, or heaters may be added in milder climates with infrequent cold snaps. In many jurisdictions, cisterns larger than 5,000 gallons require a structural design and foundation that accounts for wind and seismic loads. Despite these design challenges, nothing makes a statement of water awareness like an above-ground cistern.

Underground systems save valuable land space, are protected from the cold and can be of almost unlimited size. While they require excavation – which can increase installation costs – the material cost per gallon is usually lower for larger systems. Most commercial projects use an underground option.

material selection

There is a wide range of cistern materials to choose from (see Table 1). Because they’re often smaller, home systems offer more options, but not all scale to tens of thousands of gallons cost-effectively. This article focuses on commercial and institutional scale projects where storage requirements are thousands of gallons and larger.

Fiberglass tanks are a common choice for RWH tanks as they offer high pressure ratings and resist corrosion. They are primarily used underground and can be up to 60,000 gallons and 12 feet in diameter. While durable, they are often not the most economical choice and require special care in handling and installation. Because they are built as continuous tanks, the large sizes require oversized transport loads that add to the overall cost. Multiple tanks are required for large systems.

Polyethylene tanks can be used for underground cisterns and can be a very affordable choice for small systems under 3,500 gallons. They are lightweight, easy to transport and easy to handle on site. They can be difficult to implement in many sites as they require significant coverage but are limited in depth meaning there is a narrow area in which to position the inlet pipe. Many tanks need to be connected together to create even medium-sized systems, which can compensate for cost savings.

Steel Reinforced Polyethylene (SRPE) cisterns are new to the market and combine the durability of polyethylene and the strength of steel in an efficient and economical package. These tanks are corrosion resistant and can last in excess of 75 years. Sections are manufactured up to 50 feet in length, and multiple sections can be combined and fused together on site to create a large, leak-proof cistern sealed to a 15 psi rating. SRPE is easily repaired in the field if damaged and can handle a burial to a depth of 30 feet. For cisterns larger than 20,000 to 30,000 gallons, they can also be the most cost-effective option (see Figure 2).

Plastic crates were previously only used for infiltration, but with a waterproof liner they are also an entry-level cistern option. The lining is installed in front of the boxes. Because liners can be prone to damage and installation errors, they often have a much shorter lifespan than other cistern options. They are an economical solution for sites that require large storage volumes as they do not require heavy equipment for installation. More economical crates are typically not strong enough for more than 6 feet of coverage, so larger coverage increases costs. As there is no access for maintenance, the projected lifetime of these systems could be less than 20 years.

Concrete structures can also be used as cisterns. They can be prefabricated for faster installation or cast on site to meet specific site constraints. To achieve a watertight system, joints must be sealed with extra care and the engineer should require a coating suitable for reuse applications as people and the environment come into contact with the water. Concrete can leak through cracks over time and in most cases must be drained to seal the leak. For small to medium sized systems, concrete can be a more expensive option. However, for very large systems, concrete structures may offer better economic value and are worth considering if the cistern will be subjected to high loads.

Fabricated steel tanks are another common liquid storage option and can be extremely tough, with a lifespan of 50 years or more in the right conditions. They can be painted or coated to extend their life, but can be very expensive and also limited in size.

Watertight corrugated iron cisterns are another newer water storage option. Thin steel with an aluminum alloy coating provides a cost effective system and can last in excess of 75 years under many conditions. These lightweight tanks can be built up to 12 feet in diameter and up to 50 feet in length. Because these tanks are new to the market, engineers should request test documentation from a reputable supplier prior to specification. For small and medium-sized systems, these are the most economical option in most situations.

Above-ground metal cisterns are the most common above-ground option and use thinner steel for structure and an impervious liner for containment. There are two types of systems: curved panels that are assembled on site and monolithic built-in structures. Tanks built on site can be larger in diameter, but it can take days to assemble the steel plates and fasten thousands of bolts. Monolithic cisterns can be up to 15 feet in diameter. Because they come fully assembled, installation can be completed in a matter of hours. Both types can last 75 years or more because the above-ground environment can be less corrosive than the underground.

design considerations

Sizing a flush tank to meet LID rules is challenging as most jurisdictions provide limited guidance and existing tools do not yet include RWH. Sizing is best done with a continuous daily simulation model that calculates effluent collected, overflow and discharged effluent, service water savings, and make-up water required. While this topic deserves its own discussion in a separate article, there are fundamental relationships that are important to understand. There is a limit to the percentage of runoff reduction RWH can achieve. For sites where the annual reuse demand is less than the annual runoff, the runoff reduction limit is simply the reuse demand divided by the annual runoff volume. No matter the size of the cistern, this threshold cannot be crossed. Even for sites where the demand for reuse is greater than the annual runoff volume, increasing cistern size offers diminishing returns due to the seasonality of rainfall at most sites. It is usually better to include more reuse applications to increase reuse demand than to increase cistern size beyond the standard water quality levels typically in place today.

Durability is an important design consideration and different material types offer a wide range of life expectancies. Similar to restraint systems, it is imperative to select a material that will endure under local conditions for the life of the project, which can last many decades. Unlike retention systems, where structural integrity is paramount, cisterns must remain watertight throughout their lifetime. For example, systems that depend on liners can have significantly shorter lifespans because they are prone to leaking and cannot be repaired. While underground metal cisterns can have a designed lifespan in excess of 50 years in many situations, some locations have floors that can corrode metals. Other materials may be better suited to these situations. Ultimately, the best solution depends on the desired lifespan and local soil conditions.

Load capacity is a key factor when choosing a cistern. For commercial scale systems, cisterns can be large, like restraint systems, and often it makes sense to install them under a parking lot. Some of the smaller, entry-level cisterns have limited loading capacity, so it may be better to place them in a green area. For project sites with seasonally high groundwater, the cistern manufacturer should provide buoyancy calculations. Most cisterns can be fitted with buoyancy safeguards to prevent buoyancy. Box-built cisterns should be avoided in this situation as they cannot be strapped down effectively.

Installation and handling can be an overlooked design factor when choosing a flush tank. Many materials – like fiberglass – require rock backfill and are not strong enough to be backfilled with native soil. For large systems, these costs can add up. With other materials such as SRPE, depending on the quality of the native soil, it may be possible to use a suitable native material as a backfill for the cistern. Using local materials as backfill can save the cost of exporting excavated earth and importing expensive stone. In addition, some materials need to be handled with care and have low impact resistance; Bumps and dents created during unloading and installation can be costly to repair and disrupt project plans.

maintenance

All stormwater systems require maintenance to continue to function effectively, and RWH is no exception. Unfortunately, many owners today do not care that their rainwater BMP is not working due to lack of maintenance. What is unique about RWH and cisterns is that owners rely on their continued operation and the associated energy savings. Ease of access and maintenance are more important with cisterns and RWH systems than with other LID practices.

Quarterly inspections are recommended during the first year to assess site stress and verify initial operations. After that, annual inspections should suffice. The inspection process is simple: check the inlet, floating outlet and overflow for blockages and the amount of accumulated sediment. A one-acre drainage area will generate nearly 1 million gallons of runoff annually (in areas with 36 inches of rainfall). For many years, despite pre-treatment, the runoff will carry a significant sediment load, and eventually accumulated sediment should be removed.

In most cases, the maintenance cycles are five to ten years or longer. It is important for engineers to design access points for cleaning, inspection and repair to ensure owners benefit from the RWH system throughout the life of the system.

Closed systems that do not allow access can severely limit maintenance or repair options, and a minor installation error or internal blockage can be extremely costly or render the system obsolete. Open and accessible systems ensure the successful operation of the cistern over its entire service life.

Greg Kowalsky, BSME, is Product Manager for Low Impact Development at CONTECH Construction Products Inc. He is an active member of the American Rainwater Catchment Systems Association (ARCSA) and has six years of stormwater design experience and 15 years of engineering experience.

Kathryn Thomason, P.E., is a Senior Design Engineer at CONTECH and currently specializes in stormwater treatment, retention and stormwater harvesting.

REFERENCES

cistern water

In some areas there are attempts to collect rainwater in cisterns. In general, these cistern waters are harder and contain more solids overall than rain. This is due to the accumulation of dirt and dust on the surface of the cisterns. A study shows that in 500 domestic cisterns, the hardness was between 35 and 150 ppm. In addition, cistern water often has a high bacterial count and a striking color. While in many cases the organisms found in cisterns are non-pathogenic, it is advisable to chlorinate this water when used for drinking purposes.

Changes in traditional stormwater management practices are underway and regulators are implementing new guidelines and requirements for Low Impact Development (LID). The new rules focus on strategies to reduce runoff, including reduced sealed area and on-site infiltration. These options can be difficult to implement and are not practical in every situation. Engineers, architects and developers are designing rainwater harvesting (RWH) systems as an alternative LID practice to keep water on site and reduce runoff. Compliance with runoff reduction requirements is a compelling economic benefit for developers to justify a RWH system that would otherwise be excluded from consideration despite the environmental benefits. With the benefit of runoff reduction as its primary justification, the project is able to capture the additional benefits of LEED credits, reduced utility bills and reduced demand for municipal water systems.

RWH does not have a long history of use in modern site design, but now that it is an interesting subject many engineers and architects need to learn this multifaceted new practice. A previous CE News Professional Development Series article discussed common system components and common design requirements. This article focuses on the most central – and in many cases most expensive – component of the system: the cistern.

Basic cistern components

Cisterns come in all shapes and sizes, but there are basic characteristics that should be present in every cistern, regardless of which type is chosen (see Figure 1). The most common items to specify include the following:

Watertightness Rating – Vessels designed to hold water should be able to maintain a minimum watertightness rating for the life of the cistern. Since almost all systems are open to the atmosphere, passive head pressure is usually equal to depth. In most cases, it’s only a few pounds per square inch (psi). Tall, above-ground cisterns are the exception where 10-15 psi can be more common. Testing to ensure watertightness can be difficult on large systems, so a factory test or production standard may be the best specification requirement to ensure watertightness of the system as delivered.

Legal Requirements – Many state plumbing codes require two important elements in a cistern designed to improve water quality. The first is a stilling inlet which creates a full pipe flow within the inlet pipe and drains the incoming water from the bottom of the cistern to the top. This reduces turbulence and the potential for interfering solids that have settled to the bottom of the cistern. The second common requirement is a floating outlet. The suction hose to the pump should be flexible with an inlet strainer attached to block gross contaminants. The hose should be connected to a float so the inlet is never all the way down in the tank where solids could be sucked into the pump. It should also never be on the surface where fine floating matter may be present. The float should be suspended in the water column to ensure the cleanest water within the cistern is withdrawn. This improves the quality of the reuse water. Cisterns should also have an overflow path, vents, and screens or water traps over the inlets and outlets to prevent insect and animal access.

Pump Types and Location – There are many options for configuring pumps. Submersible pumps placed directly in the cistern or in a downstream wet well are powerful options for higher head applications, but must be hardwired to power in the cistern. Suction pumps placed above ground are also common, but are limited by depth and pressure. In many cases, a low-pressure suction pump is connected to the cistern with an additional pressure booster pump in building services.

Access and maintenance – RWH systems can have a lifespan of 20 to 50 years or even longer. Although all systems should include pre-treatment, when millions of gallons of water flow through a commercial-size system, sediment accumulates over the years. All cisterns should be equipped with multiple access points to aid in pump maintenance, inspection, repair and cleaning.

Cistern Placement: Above Ground or Below Ground?

Cistern placement is a compromise decision unique to each site, and there are many pros and cons of above-ground and below-ground configurations.

Above ground systems can be an attractive design element for a project and do not require excavation. Their size is usually limited to 10,000 to 15,000 gallons unless there is room for a large footprint or multiple cisterns. They may also need to be taken offline in cold weather, or heaters may be added in milder climates with infrequent cold snaps. In many jurisdictions, cisterns larger than 5,000 gallons require a structural design and foundation that accounts for wind and seismic loads. Despite these design challenges, nothing makes a statement of water awareness like an above-ground cistern.

Underground systems save valuable land space, are protected from the cold and can be of almost unlimited size. While they require excavation – which can increase installation costs – the material cost per gallon is usually lower for larger systems. Most commercial projects use an underground option.

material selection

There is a wide range of cistern materials to choose from (see Table 1). Because they’re often smaller, home systems offer more options, but not all scale to tens of thousands of gallons cost-effectively. This article focuses on commercial and institutional scale projects where storage requirements are thousands of gallons and larger.

Fiberglass tanks are a common choice for RWH tanks as they offer high pressure ratings and resist corrosion. They are primarily used underground and can be up to 60,000 gallons and 12 feet in diameter. While durable, they are often not the most economical choice and require special care in handling and installation. Because they are built as continuous tanks, the large sizes require oversized transport loads that add to the overall cost. Multiple tanks are required for large systems.

Polyethylene tanks can be used for underground cisterns and can be a very affordable choice for small systems under 3,500 gallons. They are lightweight, easy to transport and easy to handle on site. They can be difficult to implement in many sites as they require significant coverage but are limited in depth meaning there is a narrow area in which to position the inlet pipe. Many tanks need to be connected together to create even medium-sized systems, which can compensate for cost savings.

Steel Reinforced Polyethylene (SRPE) cisterns are new to the market and combine the durability of polyethylene and the strength of steel in an efficient and economical package. These tanks are corrosion resistant and can last in excess of 75 years. Sections are manufactured up to 50 feet in length, and multiple sections can be combined and fused together on site to create a large, leak-proof cistern sealed to a 15 psi rating. SRPE is easily repaired in the field if damaged and can handle a burial to a depth of 30 feet. For cisterns larger than 20,000 to 30,000 gallons, they can also be the most cost-effective option (see Figure 2).

Plastic crates were previously only used for infiltration, but with a waterproof liner they are also an entry-level cistern option. The lining is installed in front of the boxes. Because liners can be prone to damage and installation errors, they often have a much shorter lifespan than other cistern options. They are an economical solution for sites that require large storage volumes as they do not require heavy equipment for installation. More economical crates are typically not strong enough for more than 6 feet of coverage, so larger coverage increases costs. As there is no access for maintenance, the projected lifetime of these systems could be less than 20 years.

Concrete structures can also be used as cisterns. They can be prefabricated for faster installation or cast on site to meet specific site constraints. To achieve a watertight system, joints must be sealed with extra care and the engineer should require a coating suitable for reuse applications as people and the environment come into contact with the water. Concrete can leak through cracks over time and in most cases must be drained to seal the leak. For small to medium sized systems, concrete can be a more expensive option. However, for very large systems, concrete structures may offer better economic value and are worth considering if the cistern will be subjected to high loads.

Fabricated steel tanks are another common liquid storage option and can be extremely tough, with a lifespan of 50 years or more in the right conditions. They can be painted or coated to extend their life, but can be very expensive and also limited in size.

Watertight corrugated iron cisterns are another newer water storage option. Thin steel with an aluminum alloy coating provides a cost effective system and can last in excess of 75 years under many conditions. These lightweight tanks can be built up to 12 feet in diameter and up to 50 feet in length. Because these tanks are new to the market, engineers should request test documentation from a reputable supplier prior to specification. For small and medium-sized systems, these are the most economical option in most situations.

Above-ground metal cisterns are the most common above-ground option and use thinner steel for structure and an impervious liner for containment. There are two types of systems: curved panels that are assembled on site and monolithic built-in structures. Tanks built on site can be larger in diameter, but it can take days to assemble the steel plates and fasten thousands of bolts. Monolithic cisterns can be up to 15 feet in diameter. Because they come fully assembled, installation can be completed in a matter of hours. Both types can last 75 years or more because the above-ground environment can be less corrosive than the underground.

design considerations

Sizing a flush tank to meet LID rules is challenging as most jurisdictions provide limited guidance and existing tools do not yet include RWH. Sizing is best done with a continuous daily simulation model that calculates effluent collected, overflow and discharged effluent, service water savings, and make-up water required. While this topic deserves its own discussion in a separate article, there are fundamental relationships that are important to understand. There is a limit to the percentage of runoff reduction RWH can achieve. For sites where the annual reuse demand is less than the annual runoff, the runoff reduction limit is simply the reuse demand divided by the annual runoff volume. No matter the size of the cistern, this threshold cannot be crossed. Even for sites where the demand for reuse is greater than the annual runoff volume, increasing cistern size offers diminishing returns due to the seasonality of rainfall at most sites. It is usually better to include more reuse applications to increase reuse demand than to increase cistern size beyond the standard water quality levels typically in place today.

Durability is an important design consideration and different material types offer a wide range of life expectancies. Similar to restraint systems, it is imperative to select a material that will endure under local conditions for the life of the project, which can last many decades. Unlike retention systems, where structural integrity is paramount, cisterns must remain watertight throughout their lifetime. For example, systems that depend on liners can have significantly shorter lifespans because they are prone to leaking and cannot be repaired. While underground metal cisterns can have a designed lifespan in excess of 50 years in many situations, some locations have floors that can corrode metals. Other materials may be better suited to these situations. Ultimately, the best solution depends on the desired lifespan and local soil conditions.

Load capacity is a key factor when choosing a cistern. For commercial scale systems, cisterns can be large, like restraint systems, and often it makes sense to install them under a parking lot. Some of the smaller, entry-level cisterns have limited loading capacity, so it may be better to place them in a green area. For project sites with seasonally high groundwater, the cistern manufacturer should provide buoyancy calculations. Most cisterns can be fitted with buoyancy safeguards to prevent buoyancy. Box-built cisterns should be avoided in this situation as they cannot be strapped down effectively.

Installation and handling can be an overlooked design factor when choosing a flush tank. Many materials – like fiberglass – require rock backfill and are not strong enough to be backfilled with native soil. For large systems, these costs can add up. With other materials such as SRPE, depending on the quality of the native soil, it may be possible to use a suitable native material as a backfill for the cistern. Using local materials as backfill can save the cost of exporting excavated earth and importing expensive stone. In addition, some materials need to be handled with care and have low impact resistance; Bumps and dents created during unloading and installation can be costly to repair and disrupt project plans.

maintenance

All stormwater systems require maintenance to continue to function effectively, and RWH is no exception. Unfortunately, many owners today do not care that their rainwater BMP is not working due to lack of maintenance. What is unique about RWH and cisterns is that owners rely on their continued operation and the associated energy savings. Ease of access and maintenance are more important with cisterns and RWH systems than with other LID practices.

Quarterly inspections are recommended during the first year to assess site stress and verify initial operations. After that, annual inspections should suffice. The inspection process is simple: check the inlet, floating outlet and overflow for blockages and the amount of accumulated sediment. A one-acre drainage area will generate nearly 1 million gallons of runoff annually (in areas with 36 inches of rainfall). For many years, despite pre-treatment, the runoff will carry a significant sediment load, and eventually accumulated sediment should be removed.

In most cases, the maintenance cycles are five to ten years or longer. It is important for engineers to design access points for cleaning, inspection and repair to ensure owners benefit from the RWH system throughout the life of the system.

Closed systems that do not allow access can severely limit maintenance or repair options, and a minor installation error or internal blockage can be extremely costly or render the system obsolete. Open and accessible systems ensure the successful operation of the cistern over its entire service life.

Greg Kowalsky, BSME, is Product Manager for Low Impact Development at CONTECH Construction Products Inc. He is an active member of the American Rainwater Catchment Systems Association (ARCSA) and has six years of stormwater design experience and 15 years of engineering experience.

Kathryn Thomason, P.E., is a Senior Design Engineer at CONTECH and currently specializes in stormwater treatment, retention and stormwater harvesting.

REFERENCES

Hello – I have a cistern that I would like to use for drinking water. Our well has been pumping very little water lately and I am using…

Why does your tank need cleaning?

Even with the best leaf guards, screens and filters, sediment, plant matter and debris can settle to the bottom of your tank. While this mud may remain an untouched layer at the bottom, heavy rains can stir it up and change the color, smell, and taste of the water.

According to the Australian Department of Health, not only does your tank need to be inspected every six months, but every 2-3 years your tank needs to be thoroughly inspected for any accumulated sediment and then cleaned accordingly.

What is mud?

Sludge is the name given to the black, oozing sediment that gathers all the plant matter, waste, and other things that settle and decompose at the bottom of your water tank, providing an excellent breeding ground for harmful bacteria that can be seriously hazardous to your health.

How do you clean your tank?

If you plan to clean your own tank, follow these simple steps:

At the end of summer, when your water level should be at its lowest, drain the tank completely. Direct the water to thirsty plants in the garden to minimize waste. Switch off all pumps on the network. You may have to use the breaker – these are often hardwired. Use a high-pressure hose to thoroughly flush the inlet hose. This will remove any sludge from the walls of the inlet. Thoroughly clean the leaf guard/sieve. Replace the filter if you use one. Typically, filters last 12 to 18 months, so you’ll likely need to replace the filter more often than you clean the tank. Sweep/hoss down interior areas.

If you clean the tank yourself, you need to remember that the water level is very low and will take some time to get back to normal.

It is dangerous to climb into a tank to clean it; Be sure to take every precaution to protect yourself.

Employ a cleaning company

To avoid unnecessary water wastage, many tank cleaning companies use a vacuum to remove the sludge without affecting the water level or water quality.

It’s a great way to avoid getting into your tank to clean it, and relying on professionals will protect your water levels too. The company has the appropriate training and equipment to carry out this task safely.

The process can take a few hours, but you can safely use the water later that same day, it’s less wasteful and gives you peace of mind that the tank is professionally and hygienically clean.

Install a pump

There are some companies that can provide a pump that is specifically designed to ensure sludge doesn’t build up in the first place. These pumps can be installed after the concrete tank or added to an existing building (speak to the company for more info.)

Regular maintenance checks should still be carried out to check the integrity of the walls to ensure all inlets and outlets remain clear and there are no dead animal and/or insect problems.

Tips to keep your water in good condition

To protect and maintain the quality of your water, it is important to take steps to care for your tank.

Starting from the origin of the collection process – the gutter.

Make sure that the gutter remains free. Dead leaves can impart tannin stains to the collected water, and eventually these decaying leaves will migrate toward the tank.

Watch out for animals and birds traversing or nesting in your attic space. Check under solar panels or near tree branches – bird and animal droppings can get into the gutter and then into the water tank.

Periodically check the inlet screen; Be sure to keep it clean, otherwise you’re essentially “filtering” your rainwater through a fine mesh of decomposing leaves, dead insects, plant matter, and other debris—not a good solution.

Check both the inlet and outlet pipes to ensure they are adequately shielded to prevent animal entry. In search of a regular supply of water, small animals might try to get into your aquarium and not be able to find their way out. Dead animals affect your water supply and are unpleasant in every way.

Be sure to check the tank walls regularly for tree branches that may affect the tank walls. Fixing a small crack is a lot easier than replacing the tank, so regular visual inspections can prevent a problem before it becomes too big.

If you need more information on cleaning your tank, installing pumps or cleaning recommendations, please contact a member of our friendly team.