Sand and Sediment: Problems and Solutions
If your home's drinking water is cloudy or has floating particulates, a sediment filter may be the solution.
A sediment filter traps the particulates as water flows through it, protecting your home and appliances as well as giving you cleaner, better tasting water.
What is sediment and how does it get in our water?
Sediment is made up of small grains of organic materials like sand, silt, rust, loose scale, pipe corrosion, or clay.
Sediment can enter water supplies from a number of sources.
Sediment from the drilling process can stay in recently drilled wells. It takes about 30 days after a well is drilled and the water is used on a daily basis before the sediment has settled.
Older wells may have sediment piling up at the bottom, which could eventually be pumped into the plumbing system.
Damaged well components, including casing, screens, and seals are also potential pathways that allow sediment to enter.
Why is reducing sediment important?
In addition to making water look and taste unpleasant, sediment can clog plumbing and appliances, reduce water flow, and leave stains on clothes and fixtures.
Pollutants and pathogens can also attach themselves to sediment particles entering water supplies, leaving you at risk for waterborne illnesses and disease.
How is sediment treated?
Sediment filters act as a physical barrier to trap particulates as water flows through them.
A key dimension in the choice of filter is the filter's micron rating. The filter's micron rating is a measure of the size of particle that the filter restricts. The lower the micron rating, the smaller the particles blocked by the filter. A 10-micron filter is designed to restrict particles any larger than 10 microns in size; anything smaller than 10 microns would pass through the filter. For reference, a strand of human hair is typically around 90 microns.
You may end up trying different micron sizes and types of filters in order to remove contaminants efficiently.
Sediment filter media
Sediment filters can be manufactured with one of two materials: cellulose - manufactured from cotton fibers, or polypropylene - a plastic-based, synthetic media.
The choice of media used depends on your water source.
Households with an untreated water source such as a private well require a polypropylene filter media. Because cellulose is an organic plant fiber, microorganisms can live, grow and feed off of it. As polypropylene is made plastic, it is bacteriostatic, meaning that microorganisms will not live or grow on it.
Households using treated water may use either cellulose or polypropylene filters.
Sediment filter style
Sediment filter cartridges may be string-wound, pleated, or spun-wound.
String-wound filters look like a spool of tightly wound string. The string changes in thickness by layer, so the outer layer traps the largest particles, ultimately getting thinner to the center, which has the rating (eg. 5 micron) of the filter.
Spun Polypropylene filters are melted and blown out of a gun and spun onto a cartridge. As with string wound filters, the outer layers trap the bigger particles.
Pleated filters offer higher flow rate, lower pressure loss, and more surface area. Polypropylene pleated filters can also be washed and reused.
Sediment filtration systems
When sediment causes problems with appliances like washing machines, dishwashers, and water heaters, point-of-entry sediment filters are an effective choice for water treatment. Whole house water filtration systems should be installed as close to the point of entry of the water supply as possible. This is typically by the water heater.
For drinking water filtration, point of use systems can be used under the sink or added to a tap to address drinking water.
Sediment filters are often used as a pre-filter for other water treatments such as carbon filtration or water softeners. By trapping larger particles, sediment filters extend the life of subsequent filters in the system.