In This Article
Shock Chlorination
Water Softeners
Acid Neutralizers
Whole-House Filters
Reverse Osmosis And Distillation
Adding Unfiltered Water Line
See also Water Quality View all WATER WELL articles
In most cases, the deep well water is perfectly safe to drink, but may have nuisance problems such as mineral tastes, hardness, or acidity. Most of these issues can be solved economically. Contaminants that pose an immediate or long-term health hazard are more difficult and expensive to remove. If your water is deemed unfit to drink by your local health department, you should work with them to find a workable strategy for getting potable water to the home. In all cases, it’s wise to get the advice of an experienced professional to help devise the most effective and economical strategy for treating the particular problem you are facing.
The most common types of treatments are described below. With any system, make sure the equipment is NFS-certified for the condition or contaminant being treated and is designed to meet the flow rates required in your household. Consider maintenance needs and costs, and filter costs and service life before selecting a system.
SHOCK CHLORINATION
Household bleach can be used to treat a well and home piping contaminated with bacteria or other nuisance organisms that may cause disease or produce foul odors and tastes. This is used when a new well is built or repaired, new piping or plumbing added, floodwater has entered a well, or when iron or sulfur bacteria are causing odors or slime. The bleach is added to the well water, allowed to mix and settle, and later the well is flushed until clear of any traces of bleach. NOTE: If the bacteria are coming from a septic system, farming activities, or other ongoing sources, the problem must be solved or bacterial contamination will return.
Where ongoing chlorination is needed, consult with a water treatment expert about the feasibility and cost of automatic chlorination equipment called hypochlorinators.
WATER SOFTENERS
Water softeners reduce the calcium and magnesium ions in water that cause hardness. Most units work by binding the ions to sodium, reducing the water hardness but increasing the salt levels in the water. In areas with very hard water, the sodium levels may be high enough to pose a health risk for people on low-salt diets (a quart of very hard water, softened with sodium, will contain about 75 mg. of salt). The simplest solution is to bypass the water softener for one tap in the house used for drinking. Another more expensive alternative is to potassium chloride as the binding agent, although this can cause other health problems.
With a typical water softener, you will need to add salt every 4 to 6 weeks. Newer softeners are more efficient and may need filling every 6 to 12 weeks. A typical family of four uses about 40 gallons of salt per month. High-end systems may include monitors that tell you when to add salt. However, if you forget, the only consequence will be hard water.
All water softeners periodically run through a “regeneration” cycle that backwashes the treatment medium to remove the built-up minerals. The treatment medium, called resin, is made from tiny plastic beads that should last 10-15 years or more. A complete cycle takes about 90 minutes and works on a set schedule or only as needed on some of the newer models.
Water softeners are designed to last for many years with minimal maintenance. But with any system it is a good idea to inspect equipment at least once a month to make sure the system is working properly, to add salt if needed, and to remove any residue.
Where high salt levels in the drinking water is a concern, an expensive process called reverse osmosis (see below) can also be used to remove the sodium. A number of companies claim to offer “salt-free” water softeners. However, few if any are fully certified under NSF Standard 44 for water softeners. Make sure a unit has “system” certification, not just the component certifications required of all equipment used in potable water systems. If you are using a filter to remove iron and manganese, this should be plumbed before the water softener, as these minerals can foul the mineral elements in the softeners.
Read more on Hard Water Water Softeners
ACID NEUTRALIZERS
Two types of equipment are used in homes to neutralize acidic water that is causing problems, such as blue stains of fixtures and corrosion. The most common system is a neutralizing filter. In the other a chemical feed pump or metering pump is used to inject neutralizing chemicals.
A neutralizing filter is a simple system that runs the incoming water though a tank filled with calcium carbonate or ground limestone, and sometimes magnesium oxide or other minerals for very high acidity. Look for a system with at least 1 cubic foot of filtration media. Chemicals are typically replenished once or twice a year, depending on usage level, by the homeowner or service company
Some “active” systems use a backwash system to keep the mineral bed clean and extend its service life. These work well, but use an extra 200 gallons of water a week for a typical family. Some towns do not allow this water to be drain into the septic system.
Without a backwash system, you will need to manually flush the system once a year to prevent the calcium media from hardening into a solid mass, requiring an expensive service call. Flushing requires running incoming water back through the filter and draining it through a garden hose to outdoors or to plumbing drain. This is not difficult once you learn which valves to turn to reverse the water flow.
In a chemical feeder system, less commonly used, a small pump is used to inject a solution of soda ash (similar to baking soda) and water directly into the well or into the plumbing before it enters the pressure tank. First a small amount of soda ash is mixed with water in a holding tank, and the injection pump is activated with the well pump kicks on. Feeder systems are sometimes used with high flow rates, or when the well water contains high levels of carbon dioxide or dissolved minerals.
Soda ash injection does not increase water hardness. (A similar system can be used to lower the pH of highly alkaline water — pH above 8.5 — by injecting a weak acidic solution instead of an alkaline solution.) In addition to adding the soda ash, the pump, screens, and filters need periodic cleaning for the system to work properly.
Read more on Whole-House Acid Neutralizers.
WHOLE-HOUSE FILTERS
There are a wide range of whole-house water filters on the market – some very effective, others pretty useless. A well-designed whole-house system can supply the pressures and flow rates required of a typical household and, depending on the filter element, can filter out a wide range of contaminants. Different types of filters are used for sediment, chemicals, and minerals such as iron and magnesium. As with all water purification equipment, pay attention to flow rates and pressure drops, maintenance requirements, and the cost and service life of filters. Also make sure the system, not just the components, is NSF-certified for the contaminants in question.
- Sediment filters mechanically strain out visible particles including clay, rust, sand, and other particles that contribute to turbidity. Water with large amounts of particles may need multiple stages. Some systems use reusable filters although most are disposable.
- Iron and Manganese. Iron leaves reddish brown stains on fixtures and clothing and manganese leaves similar brown-black stains. Both have a metallic taste. Both can be filtered out with special fine filter elements, often combined with chlorination or other chemical treatments prior to filtering. Iron removal can be complicated by the presence of iron bacteria, which often form a reddish-brown slime inside toilet tanks and similar places. It’s best to consult with professionals to analyze the specific problem and optimal solution.
- Chemicals.Many chemicals that effect smell, taste, and human health can be filtered out using very fine media. Many use activated carbon to remove contaminates such as chlorine, iron, VOCs, some heavy metals, and chemicals such as hydrogen sulfide (that causes rotten egg smell).Because chemical filters can clog easily, they are often installed in series with a sediment filter, which removes and large particles from the water before it reaches the finer filter element.
REVERSE OSMOSIS AND DISTILLATION
Because of their cost and relatively slow speed of treatment, these systems are generally installed at the sink or other point-of-use, rather than treating the whole-house water supply. RO wastes up to five gallons of water for each one treated, but can remove over 99% of harmful bacteria, and 95 to 99% of most chemicals including arsenic, nitrates, lead, and toxic metals. It is effective in removing salt and is widely used in desalination systems. Membranes typically need replacement every 2-5 years and can be costly. Also pre- and post-filters need replacement every 6 months to a year, depending on the system and usage levels.
Another option for producing pure water is distillation. This is slower then RO and uses a significant amount of electricity – up to 3 kWh to produce one quart of distilled water, making this prohibitively expensive to operate in areas with high electrical costs. Distillation provides the purest treated water, so is worth considering where water quality is severely compromised.
Every type of water filtration system has maintenance costs in terms of replacing filter media and periodically servicing the system. So there is no sense in running hundreds of gallons of water through the system where filtration serves no purpose. If the issues are hard water, acidic water, or high mineral content, then you will not need to filter the water for gardening or most outdoor utility uses such as washing the car.
A simple solution is to run a line of pre-filtered water to an outdoor faucet. With well water, connect this line should T into the supply line between the pressure tank filter unit. With town water, you can add this line anywhere before the water enters the filter unit.
David says
How Do I Remove Sediment From New Well?
My well was recently drilled to 500′ and they recommended hydro fracking to increase the yield. They said it was successful and at least 2gpm recovery. They then set the pump at 300′ but even a month after I moved in I’m getting a lot of sediment in the filter. Is that normal when the pump is 200′ off the bottom of the well or should I be concerned?
buildingadvisor says
In a new well, the most likely source of excess sediment is the well drilling process itself. In many cases, the problem resolves itself within a month or two as the sediment settles to the bottom of the well.
Most types of sediment will settle out, but some types may stay in suspension. If the problem does not resolve, you may need to have the well driller flush out the well though “well surging”.
Sediment problems can also result from an unstable borehole, oversized pump, or a pump placed too close to the bottom of the well (not the case with your well). In older wells, sediment buildup can result from damage to the casing or well screen.
If all else fails you may need to install a “spin-down” filter between the well pump and the pressure tank. These remove solids by centrifugal action of the water and discard the sediment for removal. For fine-grained sediment, you may need a cartridge filter, which will need frequent filter replacements.
In choosing a filter type, the first step is water testing to help you identify the type and source of the sediment and any other contaminants.
Read more on Well Drilling Well Systems
Bruce Rowat says
UV-Light System to Purify Lake Water?
We are currently in a family discussion re: the pros and cons of an artesian well vs. drawing from a lake and using a UV light system to disinfectant same. This is for a cottage in the Laurentians, Quebec.
In general terms what are the pros and cons?
Thanks.
buildingadvisor says
In general, groundwater is cleaner and less vulnerable to pollution than surface water, such as a lake or stream. For that reason, a drilled well into a suitable aquifer will, in most cases, provide you with a reliable source of good drinking and domestic water for decades with minimal maintenance. The water may need some treatment for mineral taste, water softening, or acidity, but these are matters of convenience more than health. If you have neighbors with a drilled well (or a local well driller), they can give you a good idea of what you are likely to encounter in terms of well yield and water quality.
Drawing drinking water from the lake is a more risky proposition with more variables to consider. In most cases, you will spend less money on the initial system, but over time will spend more on system maintenance.
A properly designed UV light system can kill virtually all bacteria and other microorganisms, but it does not protect against other types of contaminants such as pesticides and other chemicals that drain off lawns and roads into the lake. It cannot remove oil or gas from motor boats, solvents, VOCs, or other pollutants that may find their way into the lake. Also, UV light also does little to improve the smell or taste of the water.
To work properly, the water flow rate must be matched to the intensity and frequency of the UV light and the water must be free of particles that cloud the water and block the penetration of the UV light. For that reason, most UV systems have a prefilter to remove any sediment or particles. Also the lamp needs to be replaced regularly to maintain effectiveness – annual replacement is recommended for safety as you cannot tell visually if the light is losing the required intensity.
A whole-house system has to be large enough to handle a significant flow rate. A point-of-use system (under-sink) can be much smaller, but does not protect you or your family during showering and other activities involving water, like filling a backyard pool.
If you are drawing from a remote lake with little boat traffic and development, a UV light system might work well. Some people combine these with an activated charcoal filter to remove any particles, odors, or tastes that might make the water less appealing.
If the lake water is less than pristine, you might also consider a reverse–osmosis (RO) system. In addition to removing microorganisms, RO removes salt, and most minerals and dissolved chemicals including prescription drugs, VOCs, and arsenic. Most RO units include pre and post filters.
For example, a high-end 5-stage RO system typically contains a sediment prefilter, two carbon block prefilters and a GAC (granular activated carbon) post filter. The better systems have longer filter life and longer membrane life. Look for a membrane that lasts at least five years, as membranes are costly. Also look for a system with easy-to-replace filters that are reasonably priced and last at least one year.
The typical RO systems discards 4 or more gallons of water for each gallon of processed water.
With any type of system, there is a wide range or quality from the cheapest to the best systems. Cheaper systems are more prone to leakage at fittings and valves. They may not be tested to industry standards by the NSF or WQA (Water Quality Association).
Whether you use well water or filtered lake water, it’s a good idea to have your water tested periodically. Contact your local health department, which can usually arrange for water testing for a nominal fee. I test my well water every couple of years as we are near the ocean and not too far from neighboring septic systems, so salt intrusion and nitrate levels are our main concerns.
Read more on Water Quality.