Water Quality & Filtration FAQ’s
What is a charcoal filter used for?
Activated charcoal is a great filter when used within the scope of its intended application. The intended applications for charcoal filtration include removal of heavy metals, chlorine and other contaminates frequently associated with taste and odor. Some proponents of charcoal filters promote them for removing bacterial contamination. This is a complete misnomer and a charcoal filter should never be used in this type of situation as charcoal can actually provide a habitat that promotes bacteriological growth!
What is Reverse Osmosis filtration used for?
Reverse Osmosis Filtration is commonly used to remove difficult contaminates. RO's can be found on a very small scale in under-sink units designed to make drinking water for a household. RO's can also be very large producing water for an entire facility, town or metropolis!
Common contaminates in our area that are commonly removed by reverse osmosis include arsenic, boron, and silica. While Reverse Osmosis filters have very fine, sub-micron filtration capability, and theoretically can filter out cysts, microbes and bacteria, an RO must have appropriate pre-treatment and post treatment before it can be effectively be used in this type of application.
Reverse Osmosis filtration is rarely used on a stand-alone basis. Pre treatment/filtration is often done to remove particulate matter and large quantities of iron or manganese. This is done to extend the life the reverse osmosis membranes. A UV light is commonly used in conjunction with RO filters to ensure that any bacteria are effectively deactivated.
Reverse Osmosis filtration produces very pure water which is naturally corrosive to the metal piping in a water system. A filter that distributes small amounts of calcite into the system should be added to keep corrosion to a minimum. When considering the use of an RO for water treatment, take into account that RO is an energy intensive technology that requires regular, high-level, maintenance. Additionally it should be considered that for every gallon of filtered water a RO system produces, anywhere from 1 to four gallons of wastewater is produced and a significant amount of electricity is consumed during this filtration process. RO membranes are relatively costly and need to be changed on a regular basis, typically about 5 years, to ensure proper operation and output.
Why do I have green staining on my fixtures?
The green staining on your fixtures is caused by corrosive water dissolving the copper in your water pipes. That copper-bearing water encounters the air at your sink faucet, oxidizes and leaves the green stain. This problem can be corrected by raising the pH of your water so that your water is no longer corrosive. The process can often involve aeration, filtration, or injection of NaOH to raise the ph levels. Sometimes combinations of these technologies are required to raise the pH effectively and ensure your piping is not dissolved from the inside-out!
Why does my water smell like rotten eggs?
The most likely reason that your water smells like rotten eggs because it contains Hydrogen Sulfide. Hydrogen Sulfide is a gas that can be harmful if it is released in an enclosed environment that humans regularly occupy. Hydrogen Sulfide is particularly dangerous in high concentrations as it is flammable and can cause death if breathed. Hydrogen sulfide is, at best, annoying at low concentrations with the ever present sulfur stink. Hydrogen Sulfide is relatively common in well water, fortunately it can be readily removed by a few different methods:
1. Air Stripping. Bubbling air through water containing hydrogen sulfide will remove the hydrogen sulfide present over a period of time. Many times filling a storage tank by spraying the water to aerate it before it collects will remove most of the Hydrogen sulfide.
2. Ozone Stripping. Ozone (O3) can be mixed with water to remove hydrogen sulfide very rapidly.
3. Adding a polymer to convert the Hydrogen Sulfide to a form that can then be filtered out. This technique usually involves very expensive 'patented' polymers that are not always effective and are usually very expensive to install.
4. Go to the source of water, typically the well, and throughly clean and chlorinate the well.
Why is my water cloudy?
1. Your water may have some air dissolved in it. Let it stand for a minute and if the water clears up, it is simply air. The small bubbles air creates rise to the surface and burst. You may want look into why you water has air dissolved in it. Air could have gotten into the piping from a leak, or a pump is sucking some air from a low water level in a tank or well.
2. Your water may have some minerals, clay or silt in suspension. If you let a small water sample sit for 24 hours undisturbed and a small discolored film or layer forms on the bottom of the container, you have suspended particles. Removal of suspended particles is usually done with a mechanical filtration process. Mechanical filtration is simply making water pass through a screen or filter media that has openings that are smaller than the particles you want to trap.
3. Your water may have iron, manganese or other minerals dissolved in it. This means that the iron, manganese or minerals will not settle out, but they can result in staining fixtures or clothing that is washed. Dissolved minerals must be removed by a specifically designed filtration method.
Oakville Pump Service has helped many of our customers resolve cloudy water problems and ensure pure clean water comes from the tap!
How do I remove pathogenic organisms from Water?
Pathogenic organisms come in many shapes and sizes ranging from bacteria, cysts, spores, viruses, protozoa, and fungus. Some pathogens are actually beneficial to our environment while others are extremely dangerous such as fecal coliform bacteria, Legionella, cryptosporidium. One of the most common paths that pathogenic organisms utilize to propagate is water!
Decontaminate the Source The first approach to a well or water supply contaminated with a pathogenic organism is to try and eliminate the source of the contamination. In cases where the contamination source is easily identified, this is simple. For example, if a storage tank has a dead animal in it, the animal would be removed and the water in the tank would be heavily chlorinated. The chlorinated water is then flushed out and the tank is refilled and re-chlorinated. This fresh chlorinated water is flushed through the distribution pipelines until chlorine is present throughout the system. The system is then flushed to remove all chlorine and a bacteria sample taken and analyzed to ensure the water is safe for consumption. If the source of contamination is not easily identified or is recurrent(such as with some water springs or shallow wells), one of the following methods of continuous pathogen removal should be implemented to insure safe water:
Ultraviolet (UV) light is commonly used reduce health risks posed by waterborne pathogens. Ultraviolet light works by taking away the ability of the organisms to reproduce. The key factor in the ability of pathogenic organisms to harm a human is found in the organisms ability to quickly reproduce. A single bacterium can reproduce itself into hundreds of millions of bacteria in short order if left to their own devices in your intestinal tract! If that bacteria is sterile, it cannot reproduce, and will likely cause little to no harm.
Chlorine is a common disinfectant and is often used on small, medium and large scale projects unless you are in the winemaking industry. Chlorine is injected into the water to kill or neutralize pathogenic organisms. Chlorine is usually dosed into the water so that there is an excess available to ensure that the water stays free of pathogens as it travels the long distances through distribution pipes to the households. Chlorine systems require regular water testing and maintenance. Drawbacks to chlorine usage include taste and odor problems. It is a matter of preference, but we find some residential, food and beverage customers shy away from chlorine usage.
Ozone is another technology that is commonly used to disinfect water. Ozone is a heavy duty disinfectant that literally takes the pathogenic organisms and tears them apart. Typical ozone levels used for disinfection in water are not harmful for humans and ozone does not leave an aftertaste like chlorine. Ozone is typically generated at the water treatments site and does not require the continued purchase of chlorine or other chemicals. Ozone systems, however, do require regular maintenance. Residual ozone in your water has a relatively short half-life so it is not able to disinfect long distances of contaminated pipeline.
Slow Sand Filtration Slow Sand filtration is an age old technique that requires very little energy input and can produce clean water. Slow sand filtration systems require careful design and planning as well as regular basic maintenance. Slow sand filtration requires that water move through a sand bed with a depth of 24 to 36" under minimal head pressures. A layer forms on top of the slow sand filter that digests pathogenic organisms. The first few inches of the slow sand filter catch particulate matter. One of the drawbacks of slow sand filtration is the space requirement. A system capable of providing 10 Gallons per minute would take up 40 square feet. Slow sand filtration is a "green" technology that uses natural components from our environment and no electricity to produce pure clean water. This technology is often implemented in the humanitarian projects many of our staff work with overseas since construction and maintenance are simple and straight forward with excellent quality water.
Diatomaceous Earth. Diatomaceous Earth is a technology where water is forced through a fabric that is coated with diatomaceous earth. Since DE is extremely jagged on a microscopic level, it is an excellent filter that catches suspended solids that can harbor bacteria and slices/shreds them as they are caught. DE filters require regular maintenance and a dedicated pumping system but can have a small footprint for a relatively high volume output.
There are a myriad of filtration designs, some of which utilize combinations of the above-mentioned technologies to ensure complete pathogen removal. Whichever technology(s) is utilized must be properly designed by a water professional and have regular maintenance performed in order to ensure that performance is ensured. Any specialty filtration technique, when improperly designed, installed or maintained can leave your water supply at risk of bacterial contamination. Systems that use of any type of pathogen removal should be closely monitored and regularly tested to ensure the safety of the consumer.
Is hard water Bad? DO i need a water softener?
Hard water is not "bad" but hard water may not be your preference. Hard water is caused by the existence of Calcium or Magnesium in water that causes white scaly water spots. These spots show up on your glassware, car, and windows after they are cleaned and left to air dry with water droplets on the surface. Some people prefer hard water since soft water can feel slimy when they are trying to rinse soap off in the shower. Others like soft water because it does eliminate some water spotting on things like glassware and your car or leaves hair feeling silky smooth after a wash.
Hard water can be "softened" by using a water softener. Water softeners belong to a category of filters known as ion-exchange. This means they take the “hard” mineral ions such as calcium and magnesium and substitute "soft" ions such as sodium or potassium. This means that water softeners change water chemistry, typically lowering the pH, causing the water to be more corrosive which can potentially damage any copper or iron pipe in your house. Individuals that need to be careful of sodium intake for dietary reasons should be very careful in regard to softened water as it often contains elevated levels of sodium. Softeners also require regular addition of Sodium Chloride or Potassium Chloride which is used by the filter to regenerate the ion-exchange filter media inside. This salt adds a regular cost component to as well as a potential environmental problem associated with the disposal of filter backwash water which can be salty.
what is causing the red staining in my sinks and toilets?
The red staining in your sinks and toilet bowls is often from iron in the water oxidizing/depositing on your fixtures. The iron in the water can come from two sources:
1. Relatively pure water with a very low pH. This acidic water is encountering old iron pipes, dissolving them and then depositing your dissolved piping on your fixtures! The solution in this case often involves raising the pH of your water so that it will not dissolve your pipes.
2. Your water had iron in it from the source. The iron will need to be removed with an appropriate iron filter to stop the staining.
Silica and Reverse osmosis
Silica is a hard, ceramic/sand like mineral formed from Silicon and Oxygen. It is frequently found in water supplies as a colloid or in ultra fine particulate form. Water softeners don’t remove it and carbon filters don’t remove it, neither do Iron filters or cartridge filters!
Silica is stubborn and you need a no-nonsense approach to remove it effectively. Silica moves through most filters with ease and these microscopic particles deposit on and bond with the ceramic and glass in your home. The clear glass dishes, mirrors and shower doors become hazy and the haze cannot be removed. This haze means that Silica has become chemically etched onto your glass and ceramic! Silica levels above 40 or 50 parts per million in water will eventually result in this permanent haze on your glass and ceramic surfaces. It is harmful or dangerous to drink? Fortunately the problems with Silica in water are primarily aesthetic.
With many amazing homes and resorts in the Napa Valley and silica present in much of our groundwater, Oakville Pump Service helps many of our clients with ensuring their expensive kitchens, bathrooms and dish ware remain clean and clear. Oakville Pump Service helps provide the necessary water testing and then designs & instals the proper water filtration equipment that is capable of providing pure clean water to these world class homes and facilities.
To effectively remove silica, reverse osmosis filtration is the most viable commercially available filter to reliably accomplish this task. While a simple under-sink reverse osmosis may be sufficient to help with some of the kitchen needs, this is not enough to provide for bathrooms or dishwashers. In cases where our clients have high levels of Silica, OPS works carefully with the homeowner to design a reverse-osmosis system large enough to provide pure, clean silica free water for all the bathrooms and kitchens to ensure no spots and no haze!
When considering a Reverse Osmosis water treatment system, keep in mind that this is much more than a simple filter that is plumbed into your piping! Below is a list of the common equipment installed with a whole house reverse osmosis system.
Reverse Osmosis Filter system
Pretreatment water filters to ensure high levels of iron, chlorine or hardness will not foul the reverse osmosis membranes.
Post treatment of the water from the RO filter to ensure the pH is corrected and neutralized
Reverse osmosis filters typically only process water at a rate of only a few gallons per minutes. This means that most whole house reverse osmosis systems utilize a small storage tank and booster pump to store and deliver the purified water as needed during periods of high demand.
UV water disinfection to ensure that water is not only free of silica and other minerals, but also free of pathogens.
Keep in mind with Reverse Osmosis equipment requires regular maintenance and significant electricity inputs. In addition, waste water is generated. For every 1 gallon of purified water available for use, another gallon or possibly even two gallons of water are sent away as waste. This waste water can sometimes be used for gardening or landscaping, but not in all cases.