What is Recycled Water?

Recycled, Reclaimed, Reused – How Wastewater is Being Repurposed & What You Need to Know


“Non potable water–do not drink”– you've seen that before, right? 

Aside from advising you not to drink water that’s unfit for your health, these signs often indicate the use of recycled water (also known as reclaimed water). In a world where freshwater is scarce and drinking water demand is on the rise, cities have turned to advances in engineering to treat and reuse wastewater. 

While this has been a longstanding practice for non-potable water use, some cities are working on making wastewater clean enough to drink. We know what you’re thinking–ew! But before you shake your head, let us explain what water recycling is, how it’s done, and why this may define the future of water use in cities.

Which types of water can be recycled?

The sources of recycled water are split into two main categories: blackwater and greywater.

  • Blackwater includes: mainly sewage, but can also be kitchen water, industrial wastewater, or other “high organic” sources
  • Greywater includes: water from sinks, clothes washing, shower drains, etc.

Rainwater can also be collected and used to water plants, wash clothes, or flush toilets without any treatment necessary.

Treatment & Uses for Recycled Water

Recycled water is treated depending on what it will ultimately be used for. Higher levels of treatment are required for water that humans will be more exposed to, such as food crop irrigation or drinking water. See here for a visual of water coming in and out of a recycled treatment process.

First, all water goes through a primary level of treatment using sedimentation. Then, it moves on to the two main levels of treatment–secondary and tertiary–which each have different reuse applications. 


For water reuse to be suitable for potable purposes, it must undergo tertiary treatment. Water reused for drinking is called “indirect potable reuse” if the reclaimed water is recharged in depleted groundwater basins/aquifers and surface water reservoirs before getting to the tap. Water directly piped into the water supply is called “direct potable reuse”–while researchers are developing technologies for this, direct potable reuse is not yet approved in the US.

If you've seen large, purple pipes, alongside other water pipes and mains you can be pretty sure they are carrying recycled water.

Treatment Regulations & Certifications

The Environmental Protection Agency (EPA) has regulations and guidelines for wastewater treatment for water reuse, which are fully outlined in their Guidelines for Water Reuse document. The National Science Foundation (NSF) has two certifications for recycled water and many states have their own specifications and guidelines as well. Companies who reuse water onsite become certified to prove to consumers and officials that their treatment system is adequate to safety standards.

What are the main concerns about recycled water use?

Currently, there are no documented cases of human health impacts from recycled water. However, that does not mean that we have nothing to worry about. The effects we might see from drinking reclaimed water recharged into aquifers will most likely not be immediate. Instead, they might develop over time as we become exposed to very low concentrations of chemical and microbial contaminants, such as pharmaceuticals, endocrine disruptors, and disinfection byproducts (formed during the treatment process). These concerns are not unique to recycled water, however.

Given what we know, recycled water is a low-risk solution that is necessary in places running out of available water supplies (like California) but it is critical that risk is evaluated regularly and people are informed about potential risks. 

Cities hoping to recycle water for reuse thus need to consider 1) the types of contaminants in wastewater that are unconventional in other drinking water sources; 2) how water treatment might impact those sources; and 3) what the health risks are of contaminants that are known to be potentially dangerous, even if they are not yet regulated.

Why are cities turning to recycled water?

Many cities–especially in water scarce areas–are experimenting with increasing recycled water use for a few reasons:

Saving energy & money

Most water recycling happens on site–companies treat their own wastewater and reuse it for flushing their own toilets and irrigating their lawns. Onsite water recycling decreases the need for transporting water from external sources, which saves energy and money.

Making water use more sustainable

Recycling water reduces the amount of potable water used for toilets or industrial cooling processes where it is not necessary to use clean water. It subsequently frees up more clean water to be used for drinking water, making drinking water a more sustainable, reliable resource.

Helping the environment

Water reuse decreases the outflow of polluted wastewater being discharged into oceans and rivers that can harm the local ecosystems. Recycled water also contains added nutrients and total dissolved salts from the treatment process, which–if used for irrigation–can work in place of synthetic fertilizers to stimulate agricultural growth.

Why test your water?

We've tested hundreds of water samples that contain stuff you don't want to be putting in your body. The fact is: water quality is not a matter of “pure” versus “un-pure”. Bottled water is not necessarily better for you than tap water, and treated groundwater is not necessarily better than indirect potable reuse if it's done right. Most of us at SimpleWater will drink tap water, whether it's from a well or an aquifer re-charged with recycled water.

But we go to the tap in the know. If you’re ever interested in testing your water (bottled water, well water, or city water) then we invite you to run a water quality test with our Tap Score service.

More questions on recycled water and water quality? Feel free to contact us at hello@simplewater.us!









Why is My Water Brown?

Red, Brown, Yellow – A Rusty Hue? You Might have Iron in Your Water.


Have you ever turned on your faucet expecting clear water and instead you see a mysterious red, yellow, or brown liquid? Have you ever noticed rust colored stains on your appliances or slimy red build up in your toilet? Reddish brown rust is an alarming color to see in your water, but don’t panic–it is most likely iron contamination. 

We’ve produced this handy guide to identify what type of iron contamination you might have and which types of treatments might help clear up your tap water.

How does iron get into the water supply?

Iron–the fourth most abundant mineral in the earth’s crust–is also present in groundwater; unless it is treated or filtered out, it enters the water supply. As pipes and well casings corrode and rust, they can release iron into the water as it flows through.

Will iron affect my health?

Iron is thankfully not dangerous to human health–it is in fact necessary for us to live and we consume iron in foods such as leafy green vegetables and red meat. The human body uses iron to carry oxygen in the blood, hence giving blood its rusty red color. While excessive consumption could lead to iron toxicity (the poison is in the dose, as they say), acute iron poisoning is not known to happen from tap water.

Detection & Treatment

We care about iron in water because it can cause unpleasant odors and tastes in drinking water or slimy residues and stains on our home appliances.

The form of iron that your water likely contains differs depending on whether your water comes from a (1) water utility or (2) private well

1. I use utility treated water and suspect iron contamination

Utility water (from a public water system) is filtered for iron, but treatment plants only reduce iron to levels below the legal concentration limit (0.3 mg/L)–they do not remove iron completely. Over time, small levels of iron can build up in the many miles of pipeline water must travel through before it reaches people’s homes. Disturbances to the pipes can then knock these mineral deposits loose and into the water stream, including:

  • Main pipeline breaks 
  • New construction 
  • Heavy irrigation or fire hydrant flushing 


The two most common forms of iron in public utility treated water are “ferrous” iron (“clear-water” iron) and “ferric” iron or  (“red-water” iron).

  • Clear-water iron: if your water comes out of the faucet clear but then turns red or brown after sitting
  • Red-water iron: if your water comes out of the faucet red or yellow


  • Clear-water iron: most commonly treated with a water softener. However, the filter must be changed or backwashed often, because iron will quickly plug it up.
  • Red-water iron: most commonly treated with a manganese greensand filter, but for small concentrations, a sediment filter, carbon filter, or water softener can be used.

You can also order a TapScore Essential Water Test or an Advanced City Water Test if you are unsure how to diagnose an iron contamination problem or purchase a treatment product, or if you want to know the concentration of iron in your water.

2. I use private well water and suspect iron contamination

Private well water is not usually filtered, so if there is iron in the source water or from your pipes, it will remain there until you filter it. 


Well water can contain clear-water iron or red-water iron, as public utility water can (see 1. above). It can also contain organic iron and tannins or iron bacteria, both of which are much much more difficult to remove.

  • Organic iron & tannins: iron reacts with naturally occurring tannins–organic matter from vegetation–to produce black residues. Iron can react with other naturally occurring organic acids to produce organic iron, which is usually yellow and brown.
  • Bacterial iron: iron bacteria are naturally occurring organisms that consume iron to survive, and produce a slimy red or brown biofilm in the process. They can enter a well during construction or repair.

If left untreated treated they can create an environment where more dangerous organisms can grow. Some common signs of iron bacteria include:

  • Tastes & odors: described as “swampy”, “oily or petroleum”, “cucumber”, “sewage”, “rotten vegetation”, or “musty”. The taste or odor may be more noticeable if the water hasn’t been used for a bit. 
  • Color: yellow, orange, red, or brown stains in sinks or toilets, on laundry, etc.
  • Red slimy deposits: sticky slime that is usually rust colored in toilets or pipes.

    It is best to test for iron bacteria because these symptoms could be signs of other bacteria as well.


    • Organics iron & tannins: can be treated with chemical oxidation followed by filtration. Water softeners, aeration systems, and iron filters may not work well because organic iron and tannins can “slow or prevent iron oxidation”.
    • Bacterial iron: iron bacteria are very difficult to remove, so physical removal, heat, and chemical treatment must be used. The most common treatment is “shock” chlorination, or adding a very strong chlorine solution to a well.

    If you are unsure of your iron source and it is staining your clothes or causing concerning smells, try our TapScore Essential Water Test or an Advanced Well Water Test with an iron reducing bacteria add-on.


    Iron contamination in water is not dangerous, but can cause undesirable odors, tastes, colors, stains, slimes, and in the case of iron bacteria, can create an environment for other harmful organisms to grow. Because there are so many different kinds of iron in water, you must identify which form you are dealing with to determine which type of removal treatment will work. If you own a private well, we recommend that you test your water every three years to be sure it remains clean.

    If you have any questions, be sure to email us at hello@simplewater.us!

    The Truth About Hydration


    Summer is just around the corner, and as you start to plan all your fun activities and adventures, remember to include the most important ingredient for success: water!

    And no, we don’t mean the ocean or that beautiful waterfall on your favorite hike. We mean drinking water! People tend to become dehydrated more often during the summer months, as they are outside in the warm weather and tend to perspire more while forgetting to drink water.

    Why is it important to stay hydrated?

    Water is critical to human survival, and when our bodies are deprived of it even a little bit, we see immediate effects. Losing as little as 1-2% of your body water can impair cognitive performance.

    If your body is dehydrated, your heart and muscles have to work harder, which may be problematic for the elderly or for people with heart conditions. As you get older, your body doesn’t sense thirst as readily either, which is why the elderly should be especially attentive to their water intake.

    How do I know if I’m dehydrated?

    If you’re thirsty, you’re actually already dehydrated. Thirst, however, is more of an immediate response to dehydration. Some effects of long term dehydration include:

    • Headaches
    • Lack of energy
    • Weight gain
    • Lack of cleansing/detoxification within the body
    • Weakened immune system (getting colds & flus easily)
    • Feeling lethargic or experiencing brain fog

    One of the best ways to check if you’re dehydrated throughout the day is to observe the color of your urine. If it is clear or light colored, you’ve been drinking enough water. If your urine is dark colored, you better be walking straight from the bathroom to the kitchen for a glass of water!

    What is the best way to stay hydrated?

    First and foremost, drink water regularly. A few more tips include:

    • Eating lots of fruits & vegetables: Not only do fruits and vegetables contain water, but they can also repair electrolyte imbalance, which helps your body stay hydrated. A perfect summer fruit choice is watermelon.
    • Avoiding caffeinated drinks: Though coffee and tea provide water, caffeine is considered a diuretic and simultaneously causes increased urination, which can lead to dehydration.
    • Exercising: Though this may seem counterintuitive, exercise increases circulation throughout the body, which improves electrolyte levels. When exercising make sure to drink extra water to supplement the amount you’re losing through perspiration.

    How much water should I drink per day? 

    3 Liters (or 13 cups) 

    minimum drinking water, for men

    2.2. Liters (or 9 cups)

    minimum drinking water, for women

    • The Institute of Medicine (IOM) suggests 3.7 liters and 2.7 liters are the minimum intake for food and beverages combined for men and women, respectively. The actual amount of water you should drink per day depends on your activities and the weather. Another approach that's recommended is that you drink 25-50% of your body weight in ounces of water daily. If you’re active, pregnant or breastfeeding, or if it is very warm outside, you’ll want to drink more than usual.
    •  As you’re consuming extra water this summer to stay hydrated, it is important to ensure that your tap water is great quality. We at SimpleWater have developed various water testing kits to make sure you understand your water quality and its impact on your health. Feel free to email us at hello@simplewater.us with any questions.



    How to Say No to a Free Water Test

    Have you stumbled into an advertisement for a free water test? Chances are that someone just wants to get in your home.

    Free Water Test.png

    Water treatment companies know that the easiest way to sell you $5,000+ worth of water treatment equipment is to begin by sending a salesperson in through your front door with a “free water testing kit.”

    The trouble is that these sales people and their water testing briefcases are designed to look fancy and ultimately sell you on purchasing an expensive water treatment product (with a maintenance plan.) Despite appearances, these free water tests hardly perform any more analysis on your water than a wet finger in the wind.

    The Free Water Test

    Signing up for one of these free water tests is easy (of course). You enter in your contact information online and shortly thereafter a sales rep will call you to set up a visit at your home.

    A nice person arrives at your front door, takes samples of your tap water into a jar, adds a few drops of chemical, swirls this concoction around and with great color-changing effect proclaims the bad news to you:

    “Your water quality is not good. You’re at risk of dangerous chloramines and your TDS levels are high. You really should be doing some treatment here.”

    Sadly, this fear tactic works nationwide. And all too often, it pushes unwary homeowners into spending way too much money on expensive water treatment equipment without necessarily improving water quality. Some of these people become our customers and find that they've overspent on water treatment technology before really getting details on what to treat for. 

    Of course, water treatment companies need to sell water treatment products, but they are obviously conflicted when it comes to testing and reporting on your water quality.

    Don’t Get Duped!

    The truth is that a lot of people already have great water quality at home and do not need the expensive treatment equipment. Furthermore, many homes can readily improve their water quality by spending less than 98% of the cost of these expensive brands (e.g. the cost of a $5,000 system that does the same work as a $100 filter–ask us for more details!).

    We often serve clients who come to us after hearing a murky sales pitch for one of these $7,000 treatment products. We send sampling materials, quickly analyze the water in a proper lab setting and produce our unique Tap Score Report. Most of the time no treatment is necessary, but if folks need or want it, then we provide a personalized and unbiased list of treatment options certified by NSF and WQA–available at low cost through Amazon or major hardware stores near you.

    Why Is There No Free Water Test?

    Simply put, free water tests don’t exist because proper laboratory testing entails very expensive laboratory equipment and operation by trained professional technicians.

    When an environmental testing laboratory receives your water samples, vials are carefully received and documented by professionals who prepare the water for analysis via EPA approved and industry standard testing methodologies. These testing methods have often been agreed upon by thousands of labs nationwide and include strict guidelines to ensure that water test results are accurate.

    Hours of professional time and hours of expensive machine operation don’t happen for free.

    Therefore, if someone is offering you a free water test, be very suspicious, as it is highly likely that these are the same people trying to sell you a water treatment product or bottled water subscription.

    Disclosure: We Perform Unbiased Water Testing


    We provide homeowners and renters nationwide with a reliable and affordable water testing service, called Tap Score. Unlike traditional environmental testing laboratories, we serve families and small businesses rather than large industrial clients.

    Tap Score is designed to be economical at smaller testing quantities

    Tap Score is tailored to the needs of residential customers and families who do not want to purchase hundreds of tests at a time in order to achieve lower wholesale testing costs. We spent thousands of hours building a logistics system that makes this possible.

    Tap Score includes detailed water health analysis

    After your sample is tested, you receive a detailed water quality report that explains each chemical found in your water, where it likely comes from, and what it’s known health effects are.

    Tap Score includes personalized and unbiased treatment matching

    For folks who do not like the taste of their water, or for those who detect a dangerous contaminant at elevated concentrations, we provide an unbiased list of NSF and WQA certified treatment products from a variety of vendors that are matched to your water quality issue, allowing you to affordably treat your water at home.

    Tap Score includes helpful and professional support

    We do not expect you to be a chemical engineer or water professional. Our staff on UC Berkeley campus is trained in water chemistry and water health. We will give you ongoing support in understanding your water quality issues until you find a suitable solution.

    Click Here To Learn More About Tap Score

    It’s not a free water test, but it is the best one we can imagine.


    Why Is My RO Water Filter Leaking?

    Do you have a reverse osmosis (RO) water treatment system? Is it not working properly? This is an article to help you determine why your drinking water filter is leaking and what you can do to fix your RO. 


    If you own and maintain a reverse osmosis water treatment system in your home, then you’re probably already aware that things sometimes go awry. The water quality engineers at SimpleWater have pulled together a helpful list of the most common problems people have with their Reverse Osmosis water filters at home along with the most common solutions.

    Reverse Osmosis: Problems, Solutions – A Quick Guide

    Scan the headlines below for common symptoms, causes, and solutions to water filter failures. If you have questions about your water quality or your water treatment system, please don’t hesitate to reach out to our professional water testing team.

    Scale forming on the membrane?

    Cause: Failure of the antiscalant, acid dosing device, or pH monitor

    Fix: Check your dosing equipment is working properly and monitor all changes in water quality before and after the RO system. Ask our team for help by emailing: hello@simplewater.us or clicking on our help page.

    Iron accumulation on the filters and membranes?

    (Leading to a high pressure difference and low permeate flow)

    Cause: High iron content in raw water, corroding pipes, failure of media filters

    Fix: Check pipes and media filters. Ask our team for help by emailing: hello@simplewater.us or clicking on our help page.

    Bacterial film on filters and membranes?

    (Leading to high pressure difference and low permeate flow)

    Cause: Ineffective sanitization or biocide

    Fix:  Sanitize all filters, perform microbiological analysis, check chemical dosing tanks; heck for biocide adsorption on carbon filters, check contact times and dose rates, select broad-spectrum biocide for organic content. Ask our team for help by emailing: hello@simplewater.us or clicking on our help page.

    Organic or humic content on filters and membranes?

    Cause: High organic content

    Fix: Test the feed water for TOC and color Ask our team for help by emailing: hello@simplewater.usor clicking on our help page.

    Membrane damage leading to high salts passthrough and high flux?

    Cause: Chlorine overdosing

    Fix: Perform chlorine tests, check dosing equipment, redox meters, bisulfite levels and the general location of dosing equipment. Ask our team for help by emailing: hello@simplewater.us or clicking on our help page.

    High Salt Passthrough?

    Cause: Failure of the O-ring at the permeate tube

    Fix: Check conductivity in each vessel and membrane. Ask our team for help by emailing: hello@simplewater.us or clicking on our help page.

    Bacteria and colloid fouling of micron-pre filters and membranes

    Cause: Breakthrough of your media pre-filter

    Fix: Wash your media pre-filters and add some biocide. Ask our team for help by emailing: hello@simplewater.us or clicking on our help page.