Yakima County's Nitrate
Treatment Pilot Program
Providing water treatment systems, education and technical assistance to households with individuals at high public health risk from nitrate contaminated wells.
Nitrate Treatment Options
The two most common types of treating nitrate are Point of Use (POU) filter system and Point of Entry (POE) filter system. The basic difference is that POU filter systems treat water at a single tap, normally at a kitchen sink, and POE filter systems treat water used throughout the house, normally installed with plumbing just before it enters the house so that treated water is available throughout the house.
Three types of treatment systems that can remove nitrate from your water are:
- Reverse Osmosis Unit - Reverse osmosis (RO) is the most economical method of removing 90% to 99% of all contaminants. The pore structure of RO membranes is much tighter than ultrafiltration (UF) membranes. RO membranes are capable of rejecting practically all particles, bacteria and organics >300 daltons molecular weight (including pyrogens). In fact, reverse osmosis technology is used by most leading water bottling plants.
- Distillation Unit - is probably the oldest method of water purification. Water is first heated to boiling. The water vapor rises to a condenser where cooling water lowers the temperature so the vapor is condensed, collected and stored. Most contaminants remain behind in the liquid phase vessel. However, there can sometimes be what is called carry-overs in the water that is distilled. Organics such as herbicides and pesticides, with boiling points lower than 100°C cannot be removed efficiently and can actually become concentrated in the product water. Another disadvantage is cost. Distillation requires large amounts of energy and water.
- Anion or Cation Exchange Unit – is a technique used to chemically alter the electrical charge of atoms in water – positive (cations) and negative (anions). Water softener uses this concept to alter hardness in water. This technology however is less effective in treating nitrate.
Important: All POU and POE filter systems or treatment units need maintenance to operate effectively. If they are not maintained properly, contaminants may accumulate in the units and make your water worse. In addition, some vendors may make claims about their effectiveness that are not based on science. The EPA does not test or certify treatment units, but two organizations that do are NSF International and Underwriters Laboratory.
Bottled Drinking Water - If installing a nitrate treatment system is not an option for you, you may consider purchasing bottled water for drinking and cooking from any local grocery store. There are also places where you can purchase clean drinking water by the gallon and you are allowed to bring your own water jugs. This, however, will be the most expensive option over time.